0:00 it would take between 1,000 and 81,000
0:03 years for a spacecraft to reach Alpha
0:05 centor if we used conventional
0:08 propulsion plus astronauts would have to
0:10 deal with the countless risks of the
0:12 mostly unexplored interstellar medium
0:15 but there might be a way out of this
0:17 seemingly hopeless situation GRS scale
0:20 spacecraft that rely on lasers when it
0:23 comes to traveling through space one of
0:26 such Concepts is called the swarming
0:28 Proxima centuri and it has recently been
0:31 chosen for the NASA Innovative advanced
0:34 concepts program you see traveling
0:36 through Interstellar space is a question
0:38 of speed energy and distance Proxima
0:42 centuri sits 4.25 light years away from
0:45 the solar system that's 25 trillion
0:48 miles which is incredibly far away for
0:52 comparison the farthest distance ever
0:54 traveled by a spacecraft is 15 billion
0:57 miles from Earth Voyager 1 has been
1:00 moving in outer space for more than 46
1:03 years reaching a maximum speed of over
1:05 38
1:06 mph traveling at the speeds that we can
1:09 allow at the moment will make
1:10 Interstellar Transit exceptionally long
1:13 and totally impractical and don't forget
1:16 about the energy requirements such a
1:18 journey would demand anything other than
1:21 a tiny spacecraft weighing a few grams
1:23 doesn't look feasible but the solution
1:26 might have been found bouncing photons
1:28 off of a laser sale could solve the
1:31 speed problem but since a single Photon
1:33 doesn't have much momentum a lot of them
1:36 are needed and since even in a couple of
1:38 decades we probably won't have a lot of
1:40 power available the thrust will be weak
1:43 that's why the mass of the probes has to
1:45 be minuscule not tons but grams The
1:49 Proposal suggests using a 100 gaw laser
1:52 Beamer boosting thousands of tiny space
1:55 probes with laser sails to a speed of 10
1:57 to 20% of the speed of life
2:00 this Mission concept might be ready for
2:03 development around
2:04 midcentury then the probes could reach
2:07 Proxima centuri as early as
2:10 2075 the researchers involved in the
2:12 project have already demonstrated how a
2:15 fleet of a thousand spacecraft could
2:17 deal with the difficulties of
2:19 interstellar travel while maintaining
2:21 Communications with Earth at the same
2:24 time the 8-year roundtrip time lag
2:26 caused by Interstellar distances and
2:29 general rela ity makes it impossible to
2:31 control the swarm of the probes from our
2:34 planet that's why the fleet must possess
2:36 a great degree of autonomy when it comes
2:39 to navigation and deciding what data
2:41 should be delivered to Earth one more is
2:44 Su is the cost of such a mission the
2:46 greatest expense will be the Lasser ra
2:49 while the tiny Probus might be
2:51 reasonably cheap to produce the
2:53 scientists believe that their project
2:55 can be developed with a budget of $100
2:58 billion it's not so much much compared
3:00 to the usefulness of such a mission
3:02 which is likely to be astronomical how
3:05 come Red Dwarf Proxima centor which is a
3:08 member of the alpha centor star system
3:11 has an earthlike Planet orbiting it
3:13 Proxima centor B it's the closest
3:17 exoplanet to Earth its mass is similar
3:20 to that of our planet and it travels in
3:22 the habitable zone of its parent star
3:24 which means there might be water in this
3:26 world as well as an atmosphere rich with
3:29 oxygen
3:30 this planet might Harbor life or it
3:32 could be a dry Rock in any case it's a
3:35 promising Target in the search for alien
3:37 life unfortunately we can't detect the
3:40 planet's bio signatures because our
3:43 usual methods for detecting them don't
3:45 work with Proxima centor B most
3:48 exoplanets are discovered and explored
3:50 through the transit method where a
3:51 planet regularly passes in front of its
3:54 parent star and we see a recurring dip
3:56 in the star's brightness that's how we
3:58 know that the planet is there but
4:00 Proxima centor B isn't a transiting
4:03 Planet it was discovered by a different
4:05 method when we look at the light coming
4:07 from Proxima centuri we can notice that
4:10 the gravitational pull of Proxima
4:12 centuri B makes the star wobble a bit
4:15 that's how astronomers found out that
4:17 the planet was there they also managed
4:19 to estimate its size and mass but no one
4:22 can figure out much more than that
4:25 hopefully a swarm of tiny space probes
4:27 will help us solve this mystery
4:32 [Music]
4:34 Venus has more volcanoes than any other
4:37 planet in the solar system more than
4:40 1,600 and a day on Venus measured by how
4:43 long it takes to rotate once on its axis
4:46 takes longer than the time it takes to
4:48 complete a full orbit of the sun wow and
4:51 that's just Monday an extreme greenhouse
4:54 effect warms the planet surface up to
4:57 87° F hot enough to melt out L winds
5:01 there reach the speed of 450 mph in the
5:04 middle Cloud layer faster than the
5:06 speediest tornadoes on our planet the
5:08 pressure on Venus's surface is 90 times
5:11 higher than that at sea level on Earth
5:13 what a great place for a vacation huh
5:15 and recently this incredible place has
5:18 become even more intriguing in the toxic
5:21 venutian atmosphere there's something
5:24 that might mean the existence of life
5:26 unfortunately scientists haven't had a
5:28 chance to collect any microb specimens
5:30 or snap any pictures of Life there but
5:33 they've discovered a chemical called
5:35 phosphine and it's a big
5:38 deal if it's not some previously unknown
5:41 chemistry that produces the gas then
5:43 there must be a kind of microbial life
5:46 involved in the process phosphine is
5:49 made up of three atoms of hydrogen and
5:51 one atom of phosphorus this gas is toxic
5:54 to any normal life form that needs
5:56 oxygen including us humans on our planet
5:59 phosphine can be found in places with no
6:02 or little oxygen for example marshes and
6:04 swabs the gas is created by complex
6:07 mixtures of bacteria living there they
6:10 can also be produced industrially the
6:12 weirdest thing is that phosphine isn't
6:14 supposed to be in Venus's atmosphere at
6:16 all this gas needs precise pressure and
6:19 temperature and tons of hydrogen to form
6:22 it wouldn't be all that surprising to
6:24 find it on Saturn or Jupiter the famous
6:27 gas giants but on Venus totally
6:30 unexpected there's no way phosphine can
6:32 be produced naturally on this planet
6:35 tiny amounts of it can be created during
6:37 volcanic eruptions lightning storms
6:39 minerals blown up to the surface or
6:42 meteorites entering Venus's atmosphere
6:45 but it's not nearly enough to explain
6:47 what the astronomers have observed it
6:49 would only make one 10,000th of the
6:51 phosphane the telescope saw but let's
6:54 start from the very beginning in 2017 a
6:57 group of scientists led by James Greaves
7:00 from Cardiff University started to use
7:02 the James Clerk Maxwell radio telescope
7:05 in Hawaii that's a mouthful the main
7:08 idea was to search for phosphine gas it
7:10 would be a sign of Life on Venus when
7:12 the data came back and the researchers
7:14 analyzed it they were shocked the
7:17 phosphine signal was powerful the team
7:19 checked the results several times they
7:21 wanted to make sure no other substance
7:24 mimic the presence of phosphine gas so
7:26 now does it mean there's life on Venus
7:29 well not necessarily if this gas is
7:32 created by some mysterious organisms
7:34 it's a big question how they survive on
7:37 Venus on our planet some microbes can
7:39 thrive in the environments with the
7:41 acidity of 5% but no more on Venus
7:45 though clouds are almost entirely made
7:47 of acid and even though they have a
7:49 rather Pleasant temperature of 86° f
7:52 these clouds contain more than 90% of
7:55 sulfuric acid DNA amino acids proteins
7:59 life components on Earth would be
8:01 dissolved there in the blink of an eye
8:04 the surface of the planet is too hot for
8:06 any kind of complex molecules to make up
8:08 life the venutian atmosphere is almost
8:11 50 times as dry as the driest place on
8:14 our home planet there's a theory that
8:16 microbes might hide in scarce water
8:18 droplets floating in the atmosphere but
8:21 it hasn't been proved yet right now the
8:23 research team's waiting for more
8:25 telescope time they're going to look for
8:27 other gases associated with life
8:30 but even if they find more evidence life
8:32 forms on Venus will be made up of
8:34 building blocks absolutely different
8:36 than those on Earth or they might be
8:39 protected by a sulfuric acid resistant
8:41 shell it can be made of such substances
8:44 as sulfur wax graphite or something else
8:47 we can't imagine of course some experts
8:50 question the idea of Life on Venus they
8:52 think the gas might be produced during
8:55 some geologic or atmospheric processes
8:57 happening on the planet but the
8:59 supporters of both theories agree on one
9:02 thing the discovery is extraordinary
9:05 interestingly astronomers have always
9:08 tried to find Signs of Life on giant
9:10 planets icy moons or even closer on Mars
9:14 but they've never seriously considered
9:16 Venus if additional telescope
9:18 observations and future space missions
9:20 confirm that phosphine is produced by
9:23 living organisms we can be in for a
9:25 bunch of exciting surprises then people
9:28 would know of a planet with an alien
9:30 biosphere well alien to us and this
9:33 planet would be just next door to earth
9:37 now speaking of visiting Venus though
9:39 would it be possible for people to land
9:41 on this planet after all robots are
9:43 already tooling around the red planet
9:45 surface on the proide Venus is closer to
9:48 Earth than Mars but it also has much
9:51 harsher conditions the planet is hotter
9:54 than Mercury even though Venus is almost
9:56 double the distance from the Sun the
9:58 temperatures are higher than the melting
10:00 point of many metals and some of them
10:02 like lead or bismuth can fall as snow on
10:05 the highest mountain peaks if you set
10:07 foot on the planet you'll find nothing
10:09 but Barren Rock giant basaltic Plains
10:12 are littered with volcanoes and
10:14 mountains in some places the surface
10:16 melts because of the heat underneath
10:19 after it releases some of it the rock
10:21 solidifies again if people ever go to
10:24 this planet they will most likely build
10:26 floating cities in the Clouds of Venus's
10:28 atmosphere spere at about 31 Mi above
10:32 the surface the conditions like the
10:34 pressure and gravity are similar to
10:36 those on Earth the temperature is rather
10:38 manageable too at around 167° F think
10:42 Death Valley California on a really hot
10:45 day the atmospheric pressure is half of
10:48 what we have at sea level on our planet
10:50 if you went outside you'd be fine
10:52 without a pressure suit the pressure
10:54 you'd feel would be the same as at the
10:56 top of Mount Kilimanjaro Plus this
10:59 Colony would be protected from the sun's
11:01 radiation better than one on Mars if the
11:04 atmosphere was the mission's final
11:06 destination Landing a spacecraft or
11:09 rather making it hover in the air would
11:11 look very different the idea is to use
11:14 an airship in the upper atmosphere for
11:16 long periods of time the Airship wrapped
11:19 in an arrow shell would enter the
11:21 planet's atmosphere at a speed of 24,000
11:24 ft per second in the next 7 Minutes its
11:27 speed would drop to around 50 00 ft per
11:30 second after that a huge parachute would
11:33 open it would slow the spacecraft down
11:35 even more and then things would get a
11:37 bit hectic the arrow shell not needed
11:40 anymore would drop away the Airship
11:42 would then inflate itself all the while
11:45 hurling through the atmosphere toward
11:47 the planet surface its speed would be at
11:49 least 330 ft per second it would get
11:52 larger and larger and its drag and lift
11:55 would increase soon the parachute
11:57 wouldn't be needed anymore the crew
11:59 would get rid of it and the Airship
12:01 would fill with air completely if
12:03 everything went as planned it would stop
12:06 30 Mi above Venus's surface after that
12:09 the Airship would travel around the
12:11 planet it would be moved by the wind
12:14 which can reach a speed of 220 mph at
12:16 the top of the cloud layer if you
12:19 decided to move closer to the surface
12:20 though you'd have to be extremely
12:22 careful the wind in the middle layer can
12:24 get twice faster the Airship could be
12:27 filled with a breathable mixture of
12:29 hydrogen and oxygen gases such a
12:32 combination would be less dense than the
12:34 venutian atmosphere it would provide the
12:36 needed boyancy you know to stay up there
12:39 Venus is famous for its super dense
12:41 clouds these clouds make the planet
12:43 shine bright enough to be seen from
12:45 Earth Venus reflects more than 75% of
12:48 the light that comes from the sun this
12:51 reflective Cloud layer exists thanks to
12:53 a haze of sulfuric acid droplets in the
12:55 atmosphere and they gather exactly at
12:58 the height where they Airship would
12:59 float luckily people already have a
13:02 method to overcome the problem of
13:04 acidity a few materials for example
13:07 Teflon and some types of plastic have an
13:10 amazing acidic resistance they could
13:12 protect the outsides of the ship so
13:15 let's say you needed to work on a
13:16 platform outside then you'd be able to
13:18 do it wearing only a chemical Hazard
13:21 suit and carrying necessary oxygen
13:23 supply ooh sounds like fun huh yeah me
13:27 neither
13:30 [Applause]
13:35 you're gazing up at the night sky wow
13:39 for much of our history we've been
13:40 looking for life among these stars and
13:42 the planets near
13:44 them but space has eyes too and there's
13:48 someone out there looking at us
13:51 maybe scientists claim that at least 29
13:54 distant planets may be watching us right
13:57 now
13:59 so comb your hair and smile we've so far
14:02 identified at least
14:04 1,715 neighboring star systems in the
14:07 Milky Way that can detect our planet
14:10 with conventional
14:11 telescopes these stars are located in
14:14 our galaxy so if they were to point
14:16 their telescopes at our sun sooner or
14:19 later they would see a small dot that
14:21 passes between our home star and the
14:23 Observer this is called a Transit it's a
14:27 method of detecting planets in astronomy
14:29 for example you can observe Transit
14:31 phenomenon right at home with a
14:33 telescope you have to point it at the
14:35 Sun and wait then you'll see Mercury
14:39 that's the closest planet to the Sun and
14:41 now you see it as a small dot Mercury
14:44 Transit process can last about 5 hours
14:48 and this phenomenon happens about 14
14:50 times in a century you'll be able to
14:52 observe the next transit on November
14:54 13th 2032 mark your calendar
14:59 likewise you can observe Venus the
15:02 second planet from the Sun but because
15:04 it's farther away its transits are less
15:07 frequent the last one was in 2004 and
15:11 2012 the next pair of transits is
15:13 expected in 217 and
15:16 2125 hey I won't be around
15:19 then so these star systems have the
15:22 opportunity to observe our planet but
15:25 long range telescopes work a little
15:27 differently actually The Observer will
15:30 not see a black dot with the sun in the
15:32 background the telescope will measure
15:34 the brightness of our star when Earth
15:37 begins its Transit between the Sun and
15:39 the Observer the telescope will record a
15:42 slight drop in the brightness of the
15:44 star because our planet is blocking the
15:46 path of the sun's
15:48 Rays those far away scientists of
15:51 extraterrestrial civilizations will be
15:53 able to calculate this drop in
15:55 brightness and determine the size of our
15:58 planet
16:00 but not all 1700 plus star systems may
16:03 have extraterrestrial life scientists
16:06 have narrowed it down to 29 planets near
16:09 some of these Stars they're potentially
16:11 habitable that means these planets are
16:13 roughly earthlike in size and within the
16:17 habitable zone of their host star that
16:19 means they're not too close to the star
16:21 so it's not too hot for a potential life
16:24 the water doesn't evaporate there like
16:26 in a Boiling Pot and they're not too far
16:28 away away so it's not too cold and the
16:31 water doesn't freeze into thick sheets
16:32 of ice and since water is the basis of
16:35 life we can assume that Civilization
16:38 might exist there theoretically these
16:40 planets could have seen Earth transits
16:42 in the last 5,000
16:44 years so while we were building the
16:46 Pyramids of Giza or
16:48 Stonehenge an extraterrestrial
16:51 civilization may have been watching
16:54 us one of these planets is only 11 light
16:57 years from our home
16:59 near the Ross 128 star a red dwarf in
17:02 the constellation Virgo there's an
17:05 exoplanet about twice the size of Earth
17:07 and right in the habitable zone of its
17:09 host
17:10 star theoretically the inhabitants of
17:13 this planet could see Earth Transit the
17:15 sun on a regular basis for 2,000 years
17:18 but about 900 years ago the planet lost
17:21 its position and can no longer continue
17:24 observation the other planet where Earth
17:26 can be seen transiting is 12 .5 light
17:29 years away near the star called Tea
17:32 Garden the window for observing our
17:34 planet will open there in about 29
17:37 years we're betting heavily on the
17:39 trapist one star system it hosts at
17:42 least seven exoplanets almost like our
17:44 solar system and four of them are in the
17:47 habitable zone of the star but they
17:50 won't be able to start observing Earth
17:52 until 16th centuries from
17:54 now but we can try to make contact with
17:57 these planets right now
17:59 they're all close enough to us to pick
18:01 up our radio
18:02 signals radio waves can travel through
18:05 space at the speed of light and our
18:07 planet has been emitting radio signals
18:09 continuously since
18:11 1895 so we're like noisy neighbors in
18:14 the radio spectrum if there's a planet
18:16 somewhere with an intelligent
18:18 civilization within 125 light years of
18:21 us our radio noise would have already
18:24 reached them the only problem is it
18:27 would take about the same time to get a
18:29 response from that
18:31 Civilization the other problem with
18:33 radio is that any civilization uses it
18:35 for a relatively short period even now
18:38 on Earth we use Bluetooth and fiber
18:41 optics more than radio except for maybe
18:43 traffic reports and over time all the
18:46 radio noise we create will simply
18:50 disappear also radio communication
18:52 assumes that an extraterrestrial
18:54 civilization is Advanced enough to use
18:57 this technology
18:58 but who knows maybe there are life forms
19:01 in space that are really different from
19:04 ours our radio signals already could
19:06 have reached that planet but its
19:08 inhabitants simply aren't capable of
19:10 receiving
19:11 them and the moment these life forms
19:14 build antenas to receive the signal will
19:16 no longer emit them but we don't lose
19:20 hope and we even send encrypted radio
19:22 signals into space to communicate with
19:24 extraterrestrial civilizations in 1974
19:28 we sent the aasbo message into
19:30 Interstellar
19:31 space if some civilization can decipher
19:34 it they'll get a rectangle like this it
19:37 has all the information about Humanity
19:40 at the top is our number system then the
19:42 atomic numbers and then our DNA which is
19:46 pictured below then a human being itself
19:50 of course below is a diagram of our
19:52 solar system earth the third planet from
19:55 the Sun is slightly elevated this is how
19:58 the extra terrestrial civilization will
20:00 understand which planet this message
20:02 came from below is a diagram of the
20:05 aasbo radio telescope
20:07 itself another option how to deliver a
20:10 message to a distant planet is to
20:12 literally send a mail delivery there it
20:15 could be a space probe and we've already
20:17 done that these are voyagers 1 and two
20:21 they were launched in 1977 and are still
20:24 operational in 2012 Voyager 1 became the
20:28 first ever human-made object in
20:30 interstellar space it travels to distant
20:33 stars and carries a message written on a
20:35 golden record the disc contains
20:37 greetings in 55 Earth languages a lot of
20:40 music from different parts of our planet
20:43 different sounds like ocean noise human
20:46 voices and animal
20:48 sounds in addition there are 116 images
20:52 on the record these are pictures of
20:54 people and Earthly landscapes in these
20:56 pictures there's information about the
20:58 sun and our
21:01 DNA the record case contains
21:03 instructions and a needle to play the
21:05 record there's also a map of our
21:08 Galaxy's Pulsar so that astronomers from
21:10 an extraterrestrial civilization can
21:13 find our solar system the main
21:15 disadvantage of sending a message this
21:17 way is time Voyager 1 will reach its
21:20 first stop the galise 445 star in 40,000
21:25 years Voyager 2 will reach the Ross 248
21:28 star in 42,000 years and in about
21:32 296,000 Years it'll pass Sirius the
21:35 brightest star in the night sky I can't
21:38 wait also an extraterrestrial
21:41 civilization can detect us with
21:43 calculations and formulas all it takes
21:46 is a little observation of the Sun in
21:48 Star systems with planets the host star
21:51 doesn't stand still it rotates around a
21:54 small
21:54 orbit this is because the heavy star
21:57 attracts the planet but the planet also
22:00 has its own gravity and resists this
22:03 shifts the star a little and causes it
22:05 to orbit around an extraterrestrial
22:08 civilization can calculate the shift of
22:10 the Sun and determine the mass of the
22:12 planets near the star using such a
22:15 method astronomers were able to find 548
22:20 exoplanets now suppose we made contact
22:23 with an extraterrestrial civilization
22:25 near the closest star Proxima centuri
22:28 there's indeed an exoplanet there but
22:31 radiation from the host star would
22:33 destroy any life forms but imagine we
22:36 still got a return signal it would be
22:39 the slowest chat in history because our
22:41 message would take 4.2 years to reach
22:43 the planet and we'd have to wait another
22:46 4.2 years to get a response and so we
22:49 arranged to
22:51 meet this civilization doesn't know how
22:53 to fly into space so we have to take the
22:57 first step although though Proxima
22:59 centuri is the closest star to our solar
23:01 system it takes about 73,000 years to
23:05 travel there by conventional rocket so
23:08 we have to learn to travel at the speed
23:10 of life but even then it would take 4.2
23:13 years to travel there imagine if we
23:16 found extraterrestrial life on the other
23:18 side of the Milky Way our galaxy is
23:21 100,000 light years wide so the journey
23:24 from edge to edge would take 100
23:27 millennia
23:29 so we either have to cheat the laws of
23:31 physics or transfer all of human
23:34 civilization to a giant spaceship that
23:36 will travel from star to star for
23:38 thousands of years and when it launches
23:40 from Earth only the great great great
23:42 great and many more greats of the first
23:44 crew will be able to see another star
23:47 system from the spaceship portal hey can
23:50 you move your head I'm trying to see out
23:52 the
23:55 window one of the biggest questions that
23:57 has been tor string the minds of
23:59 astronomers and common folks is why
24:01 haven't we found aliens yet you'd think
24:04 with a universe so big and filled with
24:06 tons of stars and planets we'd have
24:09 already bumped into some
24:10 extraterrestrial neighbors by now this
24:12 question was first asked by famous
24:14 physicist enrio fmy during a lunch with
24:16 his fellow scientists they were chatting
24:18 about UFO sightings and aliens and
24:21 suddenly fmy asked where is everyone it
24:24 seemed like a casual comment but it
24:26 sparked a huge debate if the universe is
24:29 packed with stars planets and the
24:31 possibility of alien life how come we
24:33 haven't seen any yet this discussion
24:36 gave birth to something we now call the
24:38 fairy Paradox it goes like this based on
24:42 what we know there should be Advanced
24:45 alien civilizations out there perhaps
24:47 even many of them they'd likely have
24:50 technology that could allow them to
24:51 travel across space or at least send us
24:54 signals to let us know they're there but
24:56 here's the kicker to despite all of our
24:59 technology and all the searching we've
25:00 done we haven't found a single shred of
25:03 solid proof that these Advanced
25:05 civilizations do exist so where are they
25:09 over the years a lot of theories trying
25:10 to explain this Paradox have seen the
25:13 light of day let's talk about some of
25:15 the most interesting ones the rare earth
25:17 hypothesis claims that Earth might just
25:19 be super rare and planets like ours with
25:23 life are incredibly
25:25 uncommon in this case we could be the
25:27 only planet in the the Milky Way
25:29 harboring life or at least intelligent
25:32 life we might also be the first
25:34 intelligent civilization in our galaxy
25:36 to reach this level of development in
25:39 other words we could be Pioneers however
25:41 unbelievable it may sound at the same
25:45 time it's not very scientific to rely on
25:47 a rare Chance some people think that
25:49 maybe Advanced civilizations were once
25:52 here but left the Milky Way perhaps they
25:55 developed the technology of interstellar
25:57 travel enabling them to fly between
25:59 galaxies or they could use other exotic
26:02 ways like wormholes hypothetical
26:04 structures connecting disperate points
26:06 in SpaceTime maybe they found more
26:09 interesting and pleasant places to live
26:11 far away from us one sad possibility is
26:14 that when a civilization becomes too
26:16 advanced it ends up destroying itself
26:19 whether through War environmental
26:21 destruction or something else it could
26:23 be that most civilizations don't last
26:25 long enough to reach out to others now
26:28 imagine an advanced civilization being
26:31 wiped out by a disease before they could
26:32 even start exploring stars in other
26:35 words it's possible that civilizations
26:37 just don't survive long enough to meet
26:40 others another hypothesis not very
26:43 flattering to us what if these aliens
26:45 are using technology that we just don't
26:47 understand maybe they're communicating
26:49 in ways we can't detect like using
26:52 signals beyond our current understanding
26:53 of physics scientists are discussing
26:56 such possibilities but haven't found any
26:58 any yet aliens might also be
27:00 intentionally avoiding us they could be
27:02 out there but staying Silent not so
27:05 eager to reveal themselves until we're
27:07 ready speaking of being ready some
27:10 people think that aliens could be
27:11 waiting for us to reach a certain level
27:13 of development before they make contact
27:16 maybe they don't want to interfere with
27:17 our growth until we're more advanced
27:20 advanced civilizations could also go
27:21 into virtual realities and if they can
27:24 live in digital worlds they might stop
27:26 caring about exploring the physical unit
27:28 Universe why bother another wild idea is
27:32 that some civilizations might go into a
27:34 type of hibernation waiting for the
27:36 universe to cool down because it might
27:39 be more energy efficient to do so and
27:41 last but not least there's this creepy
27:44 possibility that our entire universe is
27:46 a computer simulation and aliens are
27:49 hidden from us on purpose it's something
27:52 like a video game that doesn't reveal
27:54 all its Secrets at once until you get to
27:56 the next level
27:58 now let's talk about the odds of Life
28:00 out there we know that in just our
28:02 galaxy The Milky Way There are probably
28:05 around 20 billion planets that are
28:07 roughly Earth sized and located in the
28:09 habitable zone which means they're just
28:11 the right distance from their stars to
28:13 have liquid water but how many of these
28:16 planets actually have life could it be
28:19 most of them just a few or almost none
28:22 and out of the planets that do have life
28:24 how many host intelligent beings with
28:26 technology
28:28 in the 1960s a scientist named Dr Frank
28:31 Drake tried to estimate the number of
28:33 civilizations in our galaxy that could
28:35 contact us he came up with a famous
28:37 equation later called the Drake equation
28:41 it looks complicated but the idea is
28:43 pretty simple it helps us calculate the
28:46 number of intelligent civilizations
28:48 based on things like how many stars are
28:50 born each year how many have planets how
28:53 many planets could support life and how
28:56 long a civilization might last
28:59 here's what it looks like let's look
29:00 into this equation in more detail n is
29:03 the number of intelligent civilizations
29:06 that could contact us R is the rate of
29:09 star formation in our galaxy FP is the
29:13 fraction of stars with
29:15 planets NE is the average number of
29:18 planets per star that could support life
29:21 f is the fraction of those planets where
29:24 life actually develops fi is the
29:27 fraction where intelligent life
29:29 arises FC is the fraction of
29:32 civilizations that can and want to
29:35 communicate L is how long these
29:38 civilizations last before they disappear
29:41 the problem is we don't know the exact
29:43 values for most of these factors so when
29:45 we plug in numbers which we know with
29:47 large errors we get answers with very
29:49 large errors too depending on the values
29:52 the number of civilizations in our
29:54 galaxy could be anywhere from almost
29:55 zero to tens of thousands right now the
29:59 best estimate we can come up with gives
30:01 us a very small number close to zero in
30:04 other words even though our galaxy is
30:06 huge it's possible we're all alone here
30:09 or nearly alone one big reason we
30:12 haven't met any aliens yet is that even
30:15 if they do exist we might not be able to
30:17 visit them at least not with our current
30:20 technology the speed of light is a hard
30:22 limit in physics meaning nothing can
30:24 travel faster than it this makes
30:26 Interstellar travel super slow the
30:29 situation could be better if there were
30:31 exotic ways of travel such as wormholes
30:33 and warp drives one day they may turn
30:36 out to be real but so far there is
30:38 little hope for that even if we can't
30:41 meet Aliens face to face there are still
30:43 ways we might discover them one of the
30:46 biggest projects is called seti search
30:48 for extraterrestrial intelligence seti
30:51 scientists use huge telescopes to listen
30:53 for radio signals from distant planets
30:56 if an alien civilization is sending out
30:57 signals we might be able to pick them up
31:00 and if we have a very powerful telescope
31:03 we might use it to take super detailed
31:05 pictures of distant planets maybe even
31:07 earthlike ones hundreds of light years
31:09 away this could give us a whole new way
31:11 to search for signs of alien life in any
31:14 case even though we haven't found aliens
31:16 yet the search is far from over whether
31:20 it's through new technology better
31:22 understanding of physics or just
31:24 listening to the Stars we might one day
31:26 find that we're not alone in in the
31:28 universe until then the question where
31:30 is everyone keeps sparking
31:33 curiosity chances are we're going to
31:36 find life beyond Earth by 2035 and
31:39 there's no need to travel to a galaxy
31:41 far far away our Milky Way galaxy is
31:44 full of totally suitable environments
31:46 don't get too hyped up though we're
31:48 talking about microbes or chemical
31:50 markers not Hollywood like green
31:53 humanoids even so when we finally find
31:56 traces of life it will change how we see
31:58 our place in the
32:00 universe NASA's Kepler space telescope
32:03 discovered something incredible almost
32:06 every Star has planets and many of these
32:09 planets might be habitable rocky planets
32:12 like Earth and Mars are even more common
32:14 in our galaxy than gas giants like
32:16 Saturn and Jupiter also we already know
32:20 that our galaxy is very rich in water
32:23 there's water in interstellar clouds
32:25 where stars and planets form in the deis
32:27 fre discs around other stars in comets
32:30 just everywhere what's really hard
32:33 though is finding life
32:35 itself ideally to finally find it we
32:38 need to land on every single planet out
32:40 there and literally check under each
32:43 Rock but thanks to the newest research
32:45 we can at least narrow down the search
32:47 to potentially habitable
32:49 Worlds the James web Space Telescope a
32:52 super powerful telescope that was
32:54 launched into space in 2021 is on to
32:56 this it checks the atmospheres of nearby
32:59 super Earths rocky planets that are a
33:02 bit bigger than Earth it searches for
33:05 Life related gases chemicals that can
33:07 only be produced by living things and
33:10 they already found some clues for
33:12 example they detected signs of such a
33:15 chemical on a planet called
33:18 k218b this planet is 120 light years
33:21 away which is pretty close on a space
33:24 scale this planet is in the goldilock
33:26 zone which means a Zone around the star
33:29 where the temperatures are just right
33:31 for liquid water to exist it orbits a
33:34 red dwarf star the smallest type of star
33:36 there is such stars are a bit fainter
33:39 than our sun it will take about a year
33:41 to check if these hints of Life are real
33:44 if so it would mean that life is much
33:46 more common than we previously thought
33:49 but even if it's not there are 10 more
33:51 Goldilocks planets on their list to
33:54 study the James web Space Telescope is a
33:57 very very cool tool but it has limits it
34:00 can't detect small earthlike planets due
34:03 to their size to fix this NASA plans to
34:07 launch another tool the Widefield
34:09 infrared survey telescope this one will
34:12 be even better at spotting such planets
34:15 and Life rated chemicals and also we
34:18 have the seti project seti stands for
34:21 search for extraterrestrial intelligence
34:24 this project has been on a hunt for
34:26 extraterrestrial creatures since the
34:28 1980s they also believe that we'll find
34:31 signs of life within the next 10 years
34:34 not so long ago they started a super big
34:37 and cool project it's called Cosmic and
34:41 it uses an array of radio telescopes in
34:44 New Mexico you might have seen those in
34:47 the movie
34:48 contact Cosmic allows scientists to
34:51 listen to hundreds of thousands and
34:53 potentially millions of star systems at
34:56 the same time if there are any
34:59 interesting signals scientists can check
35:01 them right away instead of waiting for
35:03 weeks or even months the signals
35:05 themselves are often very sudden and
35:07 short but Cosmic can detect even the
35:10 shortest ones that last Nan seconds
35:13 Cosmic can also help with other research
35:16 like studying mysterious and unexplained
35:18 fast radio bursts or even Dark Matter
35:22 this is the biggest and most powerful
35:23 tool for searching for extraterrestrial
35:25 life we've ever created but it's not
35:28 enough to just listen why don't we reach
35:30 out ourselves NASA has sent some signals
35:34 into deep space in 2002 their deep space
35:37 Network sent a signal to the Pioneer 10
35:40 satellite but there was an obstacle in
35:43 the path a white dwarf star 27 light
35:46 years away from Earth if there's a
35:48 planet around this star perhaps the
35:50 signal reached them too if there are any
35:53 intelligent species there we could
35:56 receive a reply by
35:58 2029 the DSN keeps sending powerful
36:02 Transmissions into space these signals
36:04 will bump into 222 Stars within the next
36:08 three centuries maybe someday we'll
36:10 receive a reply from somewhere far away
36:13 but why haven't we received a response
36:16 yet there are about 200 billion galaxies
36:19 in the universe each with around 100
36:21 billion stars if just 1% of those Stars
36:25 had one planet that's still two 200
36:28 quintilian possible planets and we can
36:31 narrow it down even further if the
36:33 chance of them having life is one in a
36:35 trillion that would still leave us a few
36:37 hundred th000 planets so where is
36:41 everyone this is a famous question known
36:44 as the firmy
36:46 Paradox the first possibility isn't that
36:49 terrifying it's possible that the
36:51 universe is full of life but this life
36:53 isn't intelligent in our traditional
36:55 sense some planets might have microbes
36:58 birds or space dinosaurs this is called
37:02 the Great filter Theory it suggests that
37:05 there are certain filters that life has
37:07 to overcome in order to become
37:09 intelligent and maybe other species just
37:12 haven't overcome them yet think about it
37:15 life on earth started in the ocean then
37:17 crawled onto land Diversified into many
37:20 forms went extinct in massive events
37:23 five times evolved again and eventually
37:27 led to to humans we built societies
37:30 developed healthc care and only then
37:32 started searching for another life
37:34 there's another idea called the guian
37:37 bottleneck hypothesis which suggests
37:40 basically the same thing while it might
37:42 not be too hard for basic life to start
37:45 it's incredibly tough for that life to
37:47 survive and thrive over long periods
37:51 Venus might have had oceans and
37:52 earthlike conditions too but something
37:55 went wrong its oceans boiled away way
37:57 because of a runaway greenhouse effect
38:00 now it's sterile Mars also had liquid
38:03 water on its surface once and both the
38:05 moon and Mercury had thick atmospheres
38:08 for a short time meanwhile Earth has had
38:11 liquid water on its surface for almost
38:14 its entire existence it's super rare and
38:17 remarkable for a planet to hold
38:19 temperatures from 32 to 22° F for
38:23 millions of years so maybe it's a
38:26 mistake to look for intelligent life
38:28 especially the one that uses the same
38:30 technology as we do it evolved under
38:33 completely different conditions after
38:35 all that's also where the so-called
38:38 Drake Equation comes in it's a formula
38:41 that gives us a chance to calculate the
38:43 potential of Life becoming intelligent
38:45 on a
38:46 planet to calculate the result we need
38:49 to know several variables how many stars
38:52 there are how many of them have planets
38:55 the chance of these planets having life
38:57 and and so on unfortunately we don't
39:00 know these numbers yet and the result
39:02 might be insignificant but let's assume
39:04 that there is at least one other
39:06 intelligent species why haven't we met
39:10 yet there might be many reasons maybe
39:13 they don't think we're interesting
39:14 enough or maybe the problem is with us
39:17 perhaps we keep missing their signals or
39:19 maybe we miss the entire species itself
39:22 the universe is insanely huge and
39:24 ancient it's over 14 billion years old
39:28 if we compress Earth's entire
39:30 evolutionary history into a 24-hour Day
39:33 Life starts at 4:00 a.m. dinosaurs go
39:37 extinct at 11:40 p.m. humanlike
39:40 creatures appear 2 minutes before
39:42 midnight in this analogy humans have
39:45 existed for just 77 seconds and are
39:48 technology capable of detecting
39:50 extraterrestrial life is even newer less
39:53 than a second with such vast distances
39:56 and time spans the chances of us
39:58 existing at the same time as other
40:00 civilizations are slim if their
40:03 civilization lasted only a few Millennia
40:06 we could easily miss them entirely but
40:09 that doesn't mean we should give up our
40:11 search scientists were worried that
40:13 Earth's radio signals had dimmed over
40:15 time but a recent study showed that it's
40:18 actually the opposite the numbers of our
40:20 satellites keeps growing and this makes
40:22 our planet more
40:24 detectable by the end of the decade we
40:26 could have a 100,000 satellites making
40:29 Earth incredibly bright in the radio
40:32 spectrum if there is an advanced
40:34 civilization out there they will easily
40:36 spot us even from very far distances
40:39 astronomers are super optimistic about
40:42 it there is a high chance they'll find
40:44 extraterrestrial creatures while you and
40:47 I are still around the search for et is
40:50 on it's most definitely on with the
40:53 successful launch of the James web
40:55 telescope the search for Earth likee
40:57 planets has become a riveting topic of
40:59 worldwide attention apart from the James
41:01 web telescope other tools are being used
41:04 to find good earthlike candidates the
41:06 test satellite and the Kepler Telescope
41:08 are at the Forefront of searching for
41:10 other Earths after we first clear the
41:13 air of a few pesky philosophical
41:15 questions we'll take a close look at
41:17 these two searches and what the James
41:19 web telescope hopes to find so why are
41:22 we searching for earthlike planets well
41:24 because we can incredible advances and
41:27 Earthbound telescope technology have
41:29 enabled Ultra precise observations of
41:31 Starlight which led to the earliest
41:34 discovery of exoplanets as planets go
41:36 around Stars there's a gravitational
41:39 interaction between the planet and the
41:40 star they pull each other the planets
41:43 pull upon the star will cause the
41:45 Starlight to wobble back and forth ever
41:47 so slightly as the planet or planets
41:49 orbit the star this has always been the
41:52 case but the wobble of the staright was
41:54 never able to be detected because
41:56 Starlight always twinkles you know
41:58 twinkle twinkle Etc Adaptive Optics
42:01 inside telescopes is the technological
42:04 breakthrough that first enabled
42:05 astronomers to find exoplanets by taking
42:08 the twinkle out of Starlite mechanical
42:11 springs on the underside of telescope
42:12 mirrors bend the mirrors ever so
42:15 slightly to neutralize the Distortion
42:17 the twinkle caused by Starlight passing
42:19 through Earth's atmosphere without the
42:21 glimmer of Starlight the slight wobble
42:23 caused by planets pulling
42:25 gravitationally on the stars is observed
42:27 able the bigger the Wobble the more
42:29 planets it's called the astrometric
42:32 method of exoplanet detection isn't that
42:34 a mouthful whole star systems and
42:37 literally thousands of exoplanets were
42:39 inferred to exist around nearby Stars by
42:42 analyzing the wobbly patterns of
42:44 Starlight but the planets themselves
42:46 could not be seen suddenly our solar
42:48 system was not unique anymore
42:51 astronomers got giddy over the
42:52 inescapable conclusion that probably
42:55 every Star had planets it became
42:57 impossible not to ask the poignant
42:59 question is the earth unique or are
43:01 there other Earths what's the big deal
43:04 about finding earthlike planets anyways
43:06 well considering all the financial
43:08 resources the developed countries are
43:10 spending on finding earthlike planets it
43:12 can be said without a doubt that it's
43:14 definitely a big
43:16 deal including the launched James web
43:18 telescope which cost 10
43:21 billion the Kepler space telescope which
43:23 cost $550 million and the test satellite
43:27 which cost $200 million the investment
43:31 in finding earthlike planets is
43:32 certainly eyebrow raising now if you
43:35 keep in mind that these costs are just
43:37 for the hardware and to get a sketch of
43:39 the full magnitude of the search you
43:41 must also include the salaries of a team
43:43 of data miners PhD analysts and
43:45 postgrads all across the globe in
43:48 universities National Space agencies and
43:50 private institutions we will conclude
43:52 that finding another Earth is truly an
43:55 immense undertaking now suppose we find
43:58 one then Earth is not alone anymore it's
44:01 not that we can actually go to any of
44:03 these planets anytime soon Interstellar
44:05 travel requires some breakthroughs in
44:07 physics and technology and well we
44:09 aren't there yet but knowing that there
44:12 are planets out there in the Milky Way
44:14 that are like Earth in all the essential
44:16 respects like liquid water oxygen and
44:18 habitability will make space less foring
44:21 more welcoming more exciting to study
44:24 and explore it may also give us more
44:26 pride in our home planet and make us all
44:28 better earthlings the triple Mission
44:31 looking for other Earths the Kepler
44:33 Telescope the test satellite and the
44:35 James web telescope use distinct
44:37 approaches to find exoplanets and the
44:40 synonym test tells us what that method
44:43 is the T stands for transiting and
44:46 that's the key to the whole exoplanet
44:47 search e stands for you guessed it
44:50 exoplanets the target of the excellent
44:53 investigation of another Earth s stands
44:56 for survey because Tess looks at
44:58 hundreds of thousands of nearby stars
45:00 and S stands for satellite because Tess
45:04 is orbiting Earth unlike the James web
45:06 Space Telescope which will orbit the sun
45:09 when a planet passes in front of a star
45:11 that is called a Transit the planet will
45:13 block some of the light coming from the
45:15 Star this decrease or dimming of the
45:18 star can be measured the dimming of
45:20 Starlight tells lots of things about the
45:22 planet by knowing how bright the star is
45:25 and how much the star's light was dim by
45:27 a transition in front of the star we can
45:29 tell how giant the planet is or how
45:32 close it is but we won't know which is
45:34 it big or is it close until the planet's
45:37 orbit is also tied it means our test
45:40 satellite must take long duration videos
45:42 of the Stars ooh video of the Stars
45:45 Hollywood should like that the test
45:47 satellite doesn't have a telescope it
45:49 uses four CCD cameras to stream live
45:52 long duration videos of as many stars as
45:55 possible hundreds of thousands of stars
45:58 why so many well because for a Transit
46:00 of a planet to be observed it must pass
46:03 directly between the test satellites
46:05 cameras and the star if the planet is
46:07 not on the exact line of sight angle
46:10 between the star and Tessa's cameras it
46:12 cannot be seen because it will not cut
46:14 off any star lights planetary transits
46:17 are rare for example Venus passes across
46:20 Earth's view of the sun only every
46:22 couple hundred years yet Tessa's cameras
46:25 are seeing many planetary trans it among
46:27 the hundreds of thousands of stars it
46:29 takes streaming long duration videos of
46:32 and you know what that means it means
46:34 there must be hundreds or thousands of
46:36 times more planets than are observed by
46:38 the transiting method it is therefore an
46:41 inescapable conclusion that every Star
46:43 has planets planets are
46:48 everywhere and now the James web Space
46:51 Telescope with its giant 21t 4in wide
46:54 mirror is entering the search it is a
46:57 technological Marvel a wonder of the
46:59 modern world a miracle of advanced
47:01 engineering anticipation is reaching a
47:04 fever pitch but with the heightened
47:07 anticipation comes an almost equal
47:09 amount of trepidation and some things
47:12 can still go wrong before the James web
47:14 Space Telescope returns its first
47:16 pictures after the Hubble Space
47:18 Telescope for example was launched in
47:20 1990 a repair Mission had to be launched
47:23 in
47:23 1993 the mirror on the Hubble was not
47:26 very well ected and its pictures were
47:28 very blurry astronauts had to go up and
47:31 execute a spectacular space walk to fix
47:33 the
47:34 mirror after the fix the pictures Hubble
47:36 sent back were more precise than it was
47:39 ever designed for this is how an
47:41 improved model
47:43 appeared that cannot happen with the
47:45 James web telescope the Hubble orbits
47:47 the earth and is accessible to
47:49 astronauts the James web Space Telescope
47:51 orbits the Sun and is well beyond the
47:54 moon out of the reach of astronauts
47:56 because their there is no spacecraft
47:58 equipped to carry him there it cannot be
48:00 manually fixed if something goes
48:04 wrong adding to the challenges the James
48:07 web Space Telescope has only one onboard
48:09 camera to inspect any damage it may
48:11 suffer or mechanical malfunctions that
48:14 might develop in the harsh environment
48:16 of interplanetary space any remote fixes
48:19 will need to be done blind from Earth
48:22 the James web Space Telescope is now
48:24 fully deployed the at mirror segments
48:26 will need to be aligned to produce a
48:28 single image this critically important
48:31 process will take several months to
48:32 complete once the telescope is fully
48:34 deployed 70 of the first 286 observation
48:38 assignments of the telescope Target
48:40 exoplanets using data from previous
48:43 exoplanet searches it will not have to
48:45 waste time searching for exoplanets
48:47 their locations and orbits are already
48:49 known the James web telescope will go
48:52 right after them the James web Space
48:54 Telescope is not an optical telescope in
48:57 the same sense as the Hubble Space
48:58 Telescope or any ordinary telescope that
49:01 sees visible light it sees infrared
49:04 light the pictures of planets are
49:05 expected to be bright dots somewhat
49:07 fuzzy if they have atmospheres the
49:10 Spectra of the planets will yield the
49:12 most information about the exoplanet any
49:14 gases around an exoplanet will absorb
49:17 some Starlight as the Starlight passes
49:19 through the planet's atmospheres Suppose
49:21 there is methane in the planet's
49:23 atmosphere oxygen or carbon dioxide the
49:26 gas is that most indicate life in that
49:29 case the James web telescope will be
49:31 able to pick them up by spectroscopic
49:33 analysis an entire portrait of the
49:35 exoplanet can be formed from the
49:37 infrared information its temperature
49:39 ranges atmospheric content the
49:42 likelihood of liquid water and even the
49:44 probability of life and that's a big
49:47 deal the James web Space Telescope has
49:49 other missions to perform too it's
49:51 assigned to examine star formation and
49:53 Planet formation in nebula in the Milky
49:56 Way understanding how solar systems form
49:58 is part of the search for another Earth
50:01 by detecting infrared light the James
50:03 web Space Telescope will appear to the
50:05 farthest away galaxies galaxies whose
50:08 visible light gets blocked by dust and
50:10 gas these distant galaxies were formed
50:13 shortly after the big bag Galaxy
50:15 formation is an essential mission for
50:17 the James web telescope these most
50:20 disting galaxies are accelerating away
50:22 so fast that the light they emit is
50:25 stretched below the frequency of the
50:26 visible spectrum into the infrared the
50:29 great telescope can see these previously
50:32 invisible galaxies we hope to learn
50:34 about the mysterious dark energy that is
50:36 causing the universe to expand at an
50:38 ever increasing velocity hope is high
50:41 that the James web Space Telescope will
50:44 significantly expand our knowledge of
50:46 this amazing Universe we all live
50:52 in okay quick space riddle why is the
50:55 search for life in the the universe like
50:57 a tree because you're always looking for
51:00 a place to plant it you know plant it
51:03 plant it okay settle down anyway water
51:07 is the basis of life in any part of the
51:09 universe so potentially inhabited
51:11 planets must have liquid water on them
51:14 to support life an incredible number of
51:16 circumstances must come together for
51:18 this the planet must be in the habitable
51:21 zone of the star then the temperature
51:24 and atmospheric pressure on the planet
51:26 surface will be suitable for simple life
51:28 forms to begin to evolve a little closer
51:31 to the star and the water will evaporate
51:34 leaving no chance for oceans and seas to
51:37 form this is what happened on Venus it
51:39 has a size and mass similar to the Earth
51:42 but it's too close to the Sun and no
51:45 life can exist on its surface too far
51:47 from the star and the planet becomes too
51:50 cold water can only exist in the form of
51:53 ice on the surface and there just might
51:55 be liquid water deep
51:57 below Neptune is one example of this in
52:01 addition the planet must be solid and
52:03 have an atmosphere that protects it from
52:05 solar radiation and allows living
52:07 organisms to breathe in our galaxy alone
52:11 there are countless Stars really you
52:14 can't count on them near each one of
52:16 them may be a planet they're called
52:19 exoplanets and some of them may be in
52:21 the habitable zone and have everything
52:24 for life to form on them from a list of
52:27 4,500 known exoplanets scientists have
52:30 identified 24 that can be superhabitable
52:34 this is the type of planet that is
52:36 suitable for the Existence and evolution
52:38 of life even more than the earth such
52:42 planets must be twice as massive as the
52:44 Earth and 1.3 times larger a bigger size
52:48 means stronger gravity and a denser and
52:51 warmer atmosphere this will ensure a
52:53 greater diversity of all living
52:55 organisms on the planet in addition we
52:58 should pay attention to the host star
53:00 around which the superhabitable planets
53:03 will orbit and there should be a
53:05 McDonald's nearby ideally it should be
53:08 smaller than the Sun and have a lifespan
53:10 of at least 15 to 30 billion years for
53:14 comparison the lifespan of the sun is
53:16 under 10 billion years and it took about
53:18 4 billion for complex life forms to
53:21 appear here Stars such as the sun can
53:24 simply run out of fuel before life can
53:26 develop on its
53:28 exoplanet scientists suggest focusing on
53:31 dwarf stars they're smaller and less
53:33 luminous than the Sun but their lifespan
53:36 can be between 20 and 70 billion years
53:39 this will give living organisms enough
53:41 time to develop and evolve climactic
53:45 conditions on superhabitable planets
53:47 will also be different the average
53:49 temperature should be 8° F higher than
53:52 on Earth and there should be more water
53:55 in the form of clouds liquid and
53:57 humidity these conditions are the most
54:00 favorable for biodiversity so the whole
54:03 planet would be looking like tropical
54:05 forests on Earth all 24 candidates for
54:09 the title of better than Earth hey are
54:12 more than 100 light years away from us
54:15 and with the Advent of the new
54:16 generation of telescopes we'll probably
54:19 be able to find out exactly if there is
54:21 life there and if the conditions there
54:23 are suitable for humans now let's take a
54:26 look at the potentially inhabited
54:29 exoplanets T garden B it's an exoplanet
54:33 that orbits a red dwarf star about 12
54:35 light years away from the solar system
54:38 typically red dwarfs can emit flares
54:41 that blow away the atmosphere of the
54:42 planets in its orbit but this host star
54:45 is calm and relatively passive T garden
54:49 B has almost the same mass as the Earth
54:52 it makes a complete circle around its
54:54 star in about 5 days yep you got it
54:57 right a year on tea garden B is less
55:00 than a week on Earth hold on your hats
55:03 the furthest potential inhabited planet
55:06 is Kepler 1638 B it's in the
55:09 constellation signis about 3,000 light
55:13 years away from us it belongs to the
55:15 super Earth class it's twice as wide and
55:18 four times as heavy as our home planet
55:21 the gravity on it will feel much
55:23 stronger even a normal jump will be much
55:25 harder for you than on Earth although if
55:28 this planet is really inhabited local
55:31 life is used to such
55:33 conditions LHS
55:36 1140b this planet is very Rocky and
55:39 solid although its size is only 40%
55:42 larger than the earth it's seven times
55:44 as massive it has a strong gravity of
55:47 3.25 GS for comparison when you take off
55:51 on an airplane you experience an
55:53 overload of about 1 and 1/2 G's so on on
55:56 this planet you'd barely be able to
55:58 stand on your feet because of its large
56:01 mass this planet has a thicker
56:03 atmosphere and because of the greenhouse
56:05 effect its temperature can be above 19°
56:08 F and it rotates around its star quite
56:11 quickly it makes a full circle in just
56:14 24 days and now let's look at the
56:17 constellation Aquarius here's an ultra
56:20 cold dwarf trapist one a small planet
56:23 orbits in its habitable zone it's three
56:26 times lighter than the earth its
56:28 temperature is similar to ours but the
56:30 gravity is half as weak but we would
56:33 still feel comfortable there remember
56:36 the people that went to the moon there
56:38 the gravity is only 16% of the Earth's
56:41 that's what makes the astronauts move so
56:44 funny Kepler 452b is in a system that
56:48 resembles the older sister of ours the
56:50 hostar is only 11% older than our son
56:54 and is almost 2 billion years old older
56:57 the exoplanet itself is 6 1/2 billion
56:59 years old compared to 4 1/2 billion of
57:02 earths but these sisters are very far
57:05 from each other if you travel at the
57:07 speed of the New Horizon spacecraft it
57:10 will take about 26 million years to get
57:13 there so bring a big
57:15 lunch this is the closest exoplanet to
57:19 us Proxima centari B it orbits the Red
57:23 Dwarf Proxima centuri which is the
57:25 closest a star to the sun this planet is
57:28 just 4.2 Lighty years away from us its
57:32 size and mass are very similar to those
57:34 of the earth it probably has an icy
57:36 structure like Neptune although Proxima
57:39 centari is the closest star after the
57:42 sun we can't see it with a naked eye
57:45 because it's too
57:46 dim so all these planets including the
57:50 24 that scientists have recently found
57:53 are in the habitable zone of their host
57:55 stars and and in theory we can colonize
57:58 them and make them suitable for human
58:00 life in the future but here we'll have
58:03 to solve one big problem even the
58:06 nearest exoplanet is too far away for us
58:09 today our modern rockets can fly at five
58:12 times the speed of sound and even at
58:15 such speeds it will take us more than
58:17 100,000 years to get to proximus centari
58:20 on one of them well we need to come up
58:23 with something a bit faster to travel to
58:26 a a new home on one of these exoplanets
58:29 and perhaps scientists already have the
58:31 answer warp drive ooh this is a piece of
58:35 technology that will allow us to
58:37 manipulate space and time it creates a
58:40 kind of a bubble in which the normal
58:42 Laws of Motion don't work so the
58:45 spacecraft will be able to significantly
58:47 exceed the speed of light and this isn't
58:50 science fiction Humanity already has
58:53 such technology although just in theory
58:56 yet it's aluer warp drive and no I
58:59 didn't make that up since no object that
59:02 has mass can travel at the speed of
59:04 light we need to do one trick the
59:07 spacecraft has to move by compressing
59:09 the space in front of it and expanding
59:12 it behind it thus not only the ship is
59:15 moving but also the space time inside
59:18 this warp drive bubble and the maximum
59:21 speed can be 10 times that of light but
59:24 to warp the SpaceTime the ship must be
59:27 incredibly large and to power it will
59:30 need the amount of energy close to what
59:32 the whole planet of Jupiter generates
59:35 still recent calculations of NASA's jet
59:38 propulsion lab show that the ring around
59:41 the ship which should create the
59:43 so-called warp field shouldn't be
59:45 perfectly round as it was thought before
59:48 it can be more donut shaped ah Donuts
59:52 this will greatly simplify the design
59:54 and construction and will make it
59:56 possible to test this technology on a
59:58 spacecraft the size of a Voyager 1 Pro
60:02 even though it still seems impossible
60:04 scientists are already saying that there
60:07 is hope and while we don't know what
60:10 technology will be used in 2069 NASA
60:14 plans to launch its first Interstellar
60:16 mission to explore potentially habitable
60:19 planets outside of our solar
60:22 system various rumors say that the speed
60:25 of light can be achieved with Laser
60:27 Technology if the probe is very small it
60:30 can be launched to the alpha centari
60:32 star at almost the speed of light there
60:35 are also two other alternatives to power
60:38 spaceships these are nuclear energy and
60:41 energy from matter and antimatter
60:43 collisions oo these Technologies are
60:46 still a mystery to humanity though well
60:50 for the time being stay
60:52 [Music]
60:53 tuned 2022 and 23 have been Landmark
60:57 years for discovering new fascinating
61:00 worlds last year NASA surpassed 5,000
61:03 confirmed exoplanets the list is
61:05 incredibly diverse it includes Rocky
61:08 super Earths gas giants like Jupiter ice
61:11 giants like Neptune and so on and this
61:14 is just the beginning there might be
61:16 more than a trillion exoplanets in our
61:19 galaxy alone but the most important
61:21 question is how many of them are
61:23 habitable you know for us are there
61:25 there any planets on this list that
61:27 could have life on them or that could be
61:29 a future home for us of course there
61:32 are and in 2022 2023 we found as many as
61:37 five of them so buckle up and hang on
61:40 for a wild ride beyond our solar
61:44 system the first planet on our list is
61:46 Wolf
61:47 1069b a boring and stodgy designation so
61:51 I'll simply nickname it Wolfie because
61:53 hey who's going to stop me NASA
61:56 a new study conducted by 50 star ey
61:59 astronomers confirms something awesome
62:01 this exoplanet Wolfie which is located
62:04 just 31 light years away from us could
62:07 potentially be a rocky World in other
62:09 words theoretically it's a habitable
62:11 planet the team behind this discovery
62:14 used a technique called radio velocity
62:16 to detect the exoplanet this is a way
62:19 scientist study the movements of stars
62:21 and planets it's as if when you're
62:23 playing catch with a friend as they thr
62:25 throw the ball to you you can see it
62:27 coming closer and closer it's kind of
62:30 like radial velocity when a planet is
62:32 moving towards us it makes the stared
62:35 orbits appear to be coming closer to us
62:37 when the planet is moving away from us
62:39 it also makes the star look more distant
62:42 scientists can use this information to
62:44 figure out what the planet is doing and
62:46 how big it is and that's how they found
62:49 Wolfie this exoplanet is estimated to be
62:51 the Earth's size and about 1 and A3
62:54 times the mass of our planet it's
62:56 orbiting a red dwarf star who all call
62:59 Wolfie's Mama but here's the real kicker
63:02 Wolfie orbits within its star's
63:04 habitable zone which means it's a prime
63:07 candidate for liquid water to exist on
63:09 its surface that's like hitting the
63:11 exoplanetary jackpot ooh wish I had a
63:14 ticket the study estimates that if
63:16 Wolfie does have an earthlike atmosphere
63:19 temperatures could rise as high as 55° F
63:22 which would mean liquid water could pull
63:24 on the planet's day side but here's the
63:27 catch the exoplanet is tidally locked to
63:30 its star meaning that the same side
63:32 always faces the star just imagine one
63:35 side of the planet is always Bast in the
63:37 warmth of its star while the other is in
63:40 Eternal Darkness like Middle School just
63:43 kidding the team behind the discovery
63:45 believes it's a prime candidate for
63:47 further studies but we'll probably have
63:50 to wait another 10 years for answers
63:52 until then we'll just have to keep
63:54 searching the skies with our telescopes
63:56 and crossed
63:58 fingers our next planet is toi 700e H
64:02 what's a good nickname NASA has just
64:05 discovered a new planet that's set to
64:07 take the galaxies by storm or shall we
64:10 say by orbit I'll nickname it toys were
64:13 us it's almost the size of Earth most
64:16 likely has liquid water on its surface
64:18 and it's only 100 light years away we're
64:21 not talking about a road trip of course
64:23 but this is close enough in the grand
64:25 scheme of things
64:26 toys were us is the fourth planet in its
64:29 system and it's got a bit of a short
64:31 orbit just 28 days to Circle its star
64:34 well at least you would have a birthday
64:36 every month hooray this time the
64:39 discovery was made using the transit
64:41 method planets themselves are incredibly
64:44 small and hard to attack but when a
64:46 planet is in front of its star it blocks
64:49 some of the light coming from it making
64:51 it look a little bit dimmer as soon as
64:53 the planet moves away the star gets
64:55 brighter again so to find the planet
64:58 scientists watch very carefully to see
65:00 if the star's brightness changes if it
65:03 does that means there's probably a
65:05 planet playing hideand-seek with us and
65:07 that's how they discovered toys were us
65:10 the test mission discovered it it
65:12 discovered 66 new exoplanets and 2,100
65:16 more candidates waiting to be confirmed
65:18 Tess has been very busy creating Imaging
65:21 for 75% of the sky talk about efficiency
65:25 toy is where us is located in the
65:27 optimistic habitable zone between
65:29 planets C and D but it may be tily
65:32 locked just like Wolfie so we might have
65:34 to settle for a one-sided Water World
65:37 the discovery of toys were us is a
65:39 promising Prospect for future followup
65:41 observations and it demonstrates the
65:43 potential for tests to find even smaller
65:46 exoplanets in the future who knows it
65:49 may find a new home for Humanity Among
65:51 the Stars one day or at least a new
65:54 vacation spot
65:57 next we have twins GJ 1002b and GJ
66:03 1002c the Galaxy just got a little bit
66:06 closer to us with the discovery of two
66:08 exoplanets which I'll nickname Hansel
66:11 and grle that are just a stone throw
66:13 away from our solar system that's right
66:16 these two earthlike planets are located
66:18 less than 16 light years away which is
66:21 just a hop skip and a jump in space
66:23 terms for comparison Proxima centuri B
66:27 is the closest Earth Mass exoplanet at
66:29 4.2 Lighty years away so these two new
66:32 neighbors are among the closest to us
66:35 they both orbit a red dwarf star with
66:37 barely 1/8 the mass of the sun it's
66:40 quite cool and faint but that's okay
66:42 since both planets are very close to it
66:45 Hansel takes 10 days to orbit its star
66:48 while grle takes just over 21 days even
66:51 more birthdays I guess the discovery was
66:54 made by an international scientific team
66:56 and was no small feed the team had to
66:59 work together with two instruments
67:01 espresso and carmenes the result a cafe
67:04 lat nah what they got were measurements
67:07 so accurate you could practically count
67:09 the number of craters on the planet
67:11 surfaces the big deal is the planets are
67:14 located in the habitable zone of their
67:16 star and are just the right size making
67:19 them excellent candidates for future
67:21 atmospheric studies the lead author says
67:24 nature seems bent on showing showing us
67:26 that earthlike planets are very common
67:28 with these two we now know seven in
67:30 planetary systems quite near to the sun
67:34 who knew our neighbors could be so
67:36 friendly in conclusion the discovery of
67:38 Hansel and gredle is a giant leap for
67:41 human kind so let's all raise a glass of
67:44 H2O or whatever they drink on exoplanets
67:47 and celebrate
67:48 it the last planet on our list is LP
67:55 Bob this super Earth located about 98
67:58 light years away is roughly 40% larger
68:01 than our home planet moreover it has a
68:04 twin which I'll nickname Ray which is up
68:07 to 75% larger than Earth more space is
68:10 always good right the two planets orbit
68:12 around the red dwarf star unfortunately
68:15 Ray is quite hot to the touch with an
68:18 estimated temperature of
68:19 253° f so don't touch its sibling Bob is
68:24 located in the habitable zone of its
68:26 star making it a prime candidate for the
68:29 potential of life but let's remember
68:32 that the actual temperature of the
68:33 planets depends on their atmospheres
68:36 it's possible that Bob being the
68:38 outermost planet has a runaway
68:40 greenhouse effect making it more like
68:42 Venus than Earth so it might be too hot
68:45 to be habitable at all but let's not
68:47 lose hope yet the James web Space
68:50 Telescope launched in December 2021 is
68:53 on the case with its cuttingedge
68:55 technology and Powerful instruments
68:57 including spectrographs it can peer into
69:00 the atmospheres of exoplanets and reveal
69:02 which ones might be habitable so let's
69:05 see what it discovers this planet has
69:07 been listed as the second most favorable
69:09 habitable zone terrestrial planet now
69:12 it's on the list with seven other
69:13 earthlike planets all about 40 light
69:16 years away from us maybe they'll become
69:18 our new homes in the future maybe we
69:20 should fix the home we have but until
69:23 then enjoy this moment and celebrate all
69:26 these new discoveries who knows how many
69:28 more planets we'll find in the future
69:30 considering how much technology develops
69:32 each year thousands millions meanwhile
69:36 Bob and Ray anel and grle toys Were Us
69:39 Wolfie and her mama will all be out
69:41 there waiting for
69:44 us you take off from Earth and park your
69:46 spacecraft somewhere near the moon
69:48 you're now almost 240,000 Mi away from
69:51 your home planet that's almost 100
69:53 widths of the United States
69:56 now you take out a giant hammer and an
69:58 enormous chisel using the robotic arms
70:00 of your spaceship you place the Chisel
70:03 at the Earth's north pole and strike its
70:05 head with the hammer Earth splits open
70:08 like an eggshell and you see it another
70:11 planet it's Thea and it's hiding inside
70:14 our planet like a yolk in an egg you'd
70:17 need to go back in time 4.5 billion
70:20 years to find out how it got
70:23 there this beautiful nebula will soon
70:26 become our solar system colored dust and
70:29 various space debris are slowly coming
70:31 closer toward the Common Center soon
70:33 this jigsaw puzzle of debris becomes too
70:36 heavy and dense the temperature inside
70:38 the giant is rising soon it gets so high
70:41 that it triggers a nuclear Chain
70:44 Reaction Another Second and Bam there's
70:47 an explosion so powerful that the shock
70:50 waves travel far into dark space and the
70:52 blinding Flash from this blast can be
70:54 seen from the other side of the Milky
70:56 Way galaxy when the dust clears a little
71:00 you can see that a bright light is still
71:02 shining at the very center of the
71:04 explosion this newborn star is the sun
71:07 it weighs as much as 333,000 Earths if
71:11 the sun was a bucket you'd need 1.3
71:13 million earth-sized planets to fill it
71:16 you're interested in a small object over
71:18 there 93 million mil away from the Sun
71:21 this pile of rocks and hot lava is Earth
71:24 right now now the planet is busy forming
71:26 its core while the oceans of lava are
71:29 gradually cooling down but a few tens of
71:32 million years after the sun's birth you
71:34 notice a strange object hurdling toward
71:36 Earth it's Thea this small planet was
71:39 born at about the same time as Earth and
71:42 now it's following a crazy spiral
71:44 trajectory at enormous speed scientists
71:47 believe Thea was kind of a ball Jupiter
71:50 and Venus played with Venus was pulling
71:53 Thea in One Direction then and Big
71:55 Brother Jupiter pulled it back but the
71:58 sun makes up 99.8% of the mass of the
72:01 entire solar system that's why the star
72:04 sets its own rules it makes Thea move in
72:07 almost the same orbit as Earth so they
72:10 inevitably come closer and closer to
72:12 each other until they become Nextdoor
72:14 neighbors we see that Thea is the size
72:16 of Mars and as wide as the Atlantic
72:19 Ocean from New York to
72:22 Portugal a collision can't be avoided
72:25 Thea is traveling toward Earth at nearly
72:27 9,000 mph that's 11 times faster than
72:30 the speed of sound if the smaller Planet
72:33 crashes into Earth at a particular angle
72:35 Earth will most likely be torn apart as
72:37 well as Thea itself the Collision will
72:40 cause a huge blast visible on other
72:42 planets even on a bright day nothing
72:45 will be left but some burning dust and
72:47 debris even if Thea touches Earth only
72:50 lightly it'll still knock out a chunk of
72:52 our planet the size of Australia but the
72:55 collision with Thea happens at a perfect
72:57 45° angle it strikes the Earth at
73:00 tremendous speed the explosion literally
73:03 vaporizes huge amounts of rock and the
73:05 shock wave sends the remaining debris
73:07 into Earth's orbit a huge crater is
73:10 formed at the impact site soon it gets
73:13 filled with boiling lava the remnants of
73:16 Thea and the ejected fragments of earth
73:18 begin to orbit our planet according to
73:21 one version these fragments form Two
73:23 Moons at first they travel together but
73:26 one day they get too close to each other
73:28 and Collide forming one large space body
73:32 the other Theory claims that all the
73:34 shards start being pulled by the
73:35 remnants of Thea sometime later they
73:38 form the moon as we now know it at that
73:41 point in the past though it's just Red
73:43 Hot Rock and lava the collision at this
73:46 angle slightly tilts our planet and
73:49 accelerates its rotation it's because of
73:51 Thea that we have different seasons and
73:54 24 hours in a day Earth has lithospheric
73:57 plates these are enormous solid pieces
74:00 that make up the crust of our planet
74:02 after the collision with Thea they start
74:04 to break and crack it causes carbon a
74:07 primary component of all known life on
74:09 Earth to start moving all over our
74:12 planet so Earth gets some kind of
74:15 metabolism after a few hundred million
74:17 years the first living creatures start
74:19 to appear on our planet over nearly 4
74:22 billion years simple single celled
74:24 organisms have been evolving into the
74:26 life you see today according to
74:29 scientists such a collision is a very
74:31 rare event the probability that
74:33 somewhere out there there's a planet
74:35 like ours that has survived the same
74:37 catastrophe is extremely small this may
74:40 be the reason why we are yet to find
74:41 traces of other civilizations out there
74:44 in
74:46 space meanwhile the remains of Thea are
74:49 still here on Earth of course it doesn't
74:52 look like an entire planet stuck inside
74:54 our own most of the fragments have
74:56 melted and blended into the Earth's
74:58 crust if you take the top layer off our
75:01 planet you'll see two huge lava blobs
75:04 the size of entire continents they're
75:07 right below Africa and the Pacific Ocean
75:09 presumably these are the remains of Thea
75:12 they didn't mix with Earth's mantle
75:14 because of different densities it's like
75:16 mixing water and oil in a glass the oil
75:19 will always float up over the water and
75:21 create an even layer on top of it but if
75:24 you raise those lava patches up to the
75:26 surface they'd be 100 times higher than
75:28 Mount Everest other remains of Thea
75:31 might be on the moon the Apollo space
75:33 missions brought back many soil samples
75:35 for analysis scientists have concluded
75:38 that the Moon is very similar to Earth
75:40 in structure people could drill deep
75:43 down and take samples there then they'd
75:45 analyze the blobs from Earth if their
75:47 structure matched it'd be 100% proof
75:50 that Thea did hit Earth 4.5 billion
75:53 years ago and that's how we got the moon
75:56 but for the time being Thea remains
75:58 somewhat mysterious scientists are still
76:00 not sure that the planet actually
76:02 existed the whole idea perfectly fits
76:04 the model of the moon's creation but in
76:07 fact this incredible Collision may have
76:09 never
76:11 happened hop on the bright side of life
76:14 together with our brand new te's hoodies
76:16 and more click the link to pick your
76:17 choice now you travel 41 Lighty years
76:20 away from Earth to the Planet 55 kry e
76:24 it's about twice the size of Earth and
76:26 eight times heavier you take out your
76:28 giant hammer again and use it to hit the
76:30 Chisel the planet cracks and you see
76:33 it's a giant Diamond the temperature on
76:36 this planet is tens of times higher than
76:38 that of earth and its soil is rich in
76:41 carbon the heat puts a lot of pressure
76:43 on this carbon its structure changes
76:46 first it turns into graphite some more
76:48 pressure and graphite turns into diamond
76:52 on Earth diamonds form at depths below
76:54 60 M where the pressure is 50,000 times
76:57 greater than on the surface the
76:59 temperatures there rise over 1,000°
77:02 which is as hot as fire diamonds are
77:04 rejected closer to the surface in
77:06 volcanic eruptions still people have to
77:09 dig mines 1500 ft deep to find these
77:12 beautiful gems the golden jubilee
77:15 diamond is the biggest cut and faceted
77:17 diamond on Earth it weighs as much as a
77:19 chocolate bar and is the size of a
77:21 hamster its price is about $12 million
77:25 now imagine a diamond the size of an
77:27 entire
77:30 planet you decide to fly back to the
77:32 solar system your destination is
77:34 Jupiter's moon Europa it's as wide as
77:37 the distance between Seattle and Houston
77:39 and its mass is less than 1% the mass of
77:42 Earth its surface is enclosed in an icy
77:45 crust it's about 19 Mi thick but what if
77:49 you crack this crust with your giant
77:50 hammer wow Europa is completely covered
77:53 in water it's freezing here three times
77:56 colder than at the North Pole on Earth
77:58 the water turns into ice almost
78:00 instantly but the ocean beneath the
78:02 surface is still liquid Europa interacts
78:06 with Jupiter gravitationally just like
78:08 the moon with Earth this creates tidal
78:10 forces and heats europa's core the core
78:13 melts the ice around it the result is a
78:15 huge ocean 2 to three times larger than
78:18 all of Earth's oceans combined
78:20 scientists believe that water is the
78:22 basis of life it may mean that life may
78:25 exist on Europa there could be thermal
78:27 Springs just like at the bottom of our
78:29 oceans the water there is probably much
78:32 warmer and even though the pressure and
78:34 temperature in such places are likely to
78:35 be extreme simple bacteria may live
78:38 there Europa is almost the same age as
78:41 Earth this means there's been enough
78:43 time for living organisms to appear and
78:46 evolve who knows maybe some Advanced
78:48 civilization is already blooming under
78:50 this crust of ice they may be building
78:53 big cities and dreaming of conquering
78:55 space right now but the only thing
78:58 people can do at the moment is send a
79:00 probe to Europa and find out if life is
79:03 possible
79:04 there this is Neptune the next stop is
79:08 Pluto stand clear of the closing doors
79:11 please one day with top-notch future
79:14 Technologies One Stop from Neptune to
79:16 Pluto won't see much further than Time
79:18 Square from Bryant Park today there are
79:21 huge ice mountains on Pluto valleys that
79:23 go further than your eyes can see 160 m
79:27 large craters almost as big as the
79:29 largest one on earth and no life the
79:32 reasons are obvious the long distance
79:34 between Pluto and the sun guarantees
79:36 freezing temperatures on that dwarf
79:38 planet it also ensures a trip of a few
79:41 billion miles plus it's smaller than the
79:44 moon so it would get crowded very soon
79:47 if people started dwelling there still
79:49 there's one reason which makes life
79:51 there not that far-fetched the sun has a
79:54 lifespan and Cycles within it our solar
79:56 system used to be nothing but a cloud of
79:58 gas and dust as a result of a
80:00 gravitational collapse at the center of
80:02 this Cloud the gas and dust started
80:05 gathering in specific denser places
80:08 these pulled more and more matter as
80:10 time went on and something called
80:12 conservation momentum made the mass
80:14 start rotating and heating up because of
80:17 immense pressure later there appeared a
80:19 disc similar to what Saturn has but it
80:22 was made of entirely different
80:23 substances and right in the center there
80:26 was the ball that eventually became the
80:28 Sun a protostar is a young star that's
80:31 still Gathering its mass and that's
80:34 exactly what the sun was before the
80:36 temperatures and pressures inside of it
80:37 lighted up its core millions of years
80:40 later it became the sun we see every day
80:43 but it won't stay this way forever it
80:45 will heat up even more and eventually
80:47 get bigger and denser turning into a red
80:50 giant it may one day get big enough to
80:53 swallow up Venus and Mercury chances are
80:56 it might swallow even planet Earth even
80:59 if it doesn't devour our planet the sun
81:01 might get close enough to touch us well
81:04 if this happened life on Earth wouldn't
81:05 be possible but then in just a few
81:08 minutes the sun loses about 40% of its
81:11 mass and shrinks about 10 times what it
81:14 used to be it's not as bright and indeed
81:17 not as hot as it used to be by this
81:19 moment Earth will have already been
81:21 deserted people might want to start
81:23 traveling around base or settle down on
81:26 another planet where life is sustainable
81:28 like the exoplanet Kepler 62f which by
81:31 the way is even bigger than Earth while
81:34 all of this was happening Pluto was
81:37 changing before every resource was
81:39 frozen inside of the dwarf planet water
81:42 gases like methane carbon monoxide you
81:45 name it but as the sun was reaching its
81:47 peak Luminosity Pluto was slowly warming
81:50 up and losing a lot of what it had to
81:53 the vastness of space at the same time
81:55 an atmosphere formed up if the
81:58 atmosphere gets thick enough it would
81:59 create favorable life conditions then
82:02 instead of spaceships a tiny percentage
82:04 of us would be able to set up colonies
82:07 on the dwarf planet the temperature is
82:09 comfortable there almost t-shirt weather
82:12 it even resembles Earth a tiny bit
82:14 Canyons filled with water beautiful
82:16 endless Fields with trees and lots of
82:19 space to run around and mineral water
82:21 pockets on the ground good enough to
82:23 drink Pluto's rotations are different
82:25 than Earth's an earth day is 24 hours
82:28 and sometimes it still feels like it
82:30 never ends but on Pluto a whole rotation
82:33 around the sun takes 153 hours because
82:36 it's pretty far away from the Sun after
82:39 several hours without sleep we get tired
82:41 and our eyes get red it means we'd have
82:44 to take several naps throughout the day
82:46 on Pluto a year on Pluto equals 248
82:49 Earth years unless we come up with some
82:51 sort of technology to get us to live
82:53 that long our entire lifespan would be
82:56 less than half a year on the dwarf
82:58 planet so houses on Pluto might need to
83:01 be equipped with cryo Chambers whenever
83:04 you feel like dreaming for a long time
83:06 you jump in it and wake up 50 Pluto days
83:09 later on the dwarf planet there are also
83:12 seas and beaches so it's just like a
83:14 tiny Earth far away from the actual
83:17 Earth the food on Pluto could be tastier
83:20 we might find a way to make the
83:21 ingredients more Savory and even try to
83:23 grow them faster during the trip you
83:26 plant a carrot and 2 days later it's
83:28 ready to be in your salad there could
83:30 also be new ingredients for our salads
83:32 on Pluto maybe 2 m tall mushrooms we've
83:35 never seen before the animals we would
83:37 take with us on the trip would get
83:39 released into their new home forever and
83:42 with time they would evolve and adapt to
83:44 their new environments the law of the
83:46 Jungle could change a bit too Lions
83:49 might not be Kings anymore deer are
83:52 their antlers are twice the size of what
83:54 they used used to be but to be fair so
83:56 are the deer most of the animals that
83:58 were already here used to live
84:00 underwater but with time the amphibian
84:03 started shifting to the surface just
84:05 like Earth at the beginning of Life
84:07 Pluto could only be a temporary home
84:09 though once the sun has finally reached
84:11 its Final Phase Pluto would get Frozen
84:14 and lifeless again people instead would
84:16 need to try to find a planet that stays
84:18 in the goldilock zone of another galaxy
84:21 the goldilock zone is the exact proper
84:24 distance from the Star like the sun
84:26 where the temperature is perfect for the
84:27 water to stay liquid it's the rule
84:30 scientists search for when looking for
84:31 other planets that can sustain life we
84:34 can try setting new colonies on one such
84:36 planet or even try to set up our own
84:38 artificial home not exactly a planet or
84:40 a spaceship but a combination of both
84:43 something huge built right in space say
84:46 a wheel with gravity everywhere we go so
84:48 we don't fall off it would float in
84:50 space toward the new exoplanet capable
84:53 of fitting enti States in this whole
84:56 trip might happen just because the sun
84:58 first grew too much and then having
85:00 reached the culmination of its life
85:01 cycle it would finally become a white
85:04 dwarf it's going to be a pretty long
85:06 journey and entire Generations will be
85:08 born here you'll have a choice sleep
85:11 your way through the Journey until
85:12 humans finally reach their new exoplanet
85:14 or enjoy the trip in this fantastic
85:17 spaceship there's all you need on board
85:19 malls bigger than those on Earth large
85:21 futuristic cities even places to farm
85:24 Fields with rich soil made artificially
85:27 and finally after a long journey the
85:30 exoplanet it's even somewhat better than
85:33 Earth the planet is Giant and has more
85:35 continents the continent's center isn't
85:38 as far from oceans which means there
85:40 aren't as many desert areas though the
85:42 sun of this planet is an orange dwarf
85:44 it's not as hot as our yellow dwarf sun
85:46 today it's a bit smaller but here's the
85:49 kick orange dwarfs live somewhat longer
85:52 they remain stable for between 15
85:54 billion and 45 billion years despite
85:57 that this new planet is full of
85:59 rainforests because the planet itself is
86:02 warmer it means more biodiversity and
86:05 creatures we've never seen before but
86:07 even if nothing out there is suitable we
86:09 could try and terraform this planet
86:11 instead if we take Mars as an example we
86:14 could create a greenhouse effect by
86:16 Smashing icer comets and releasing
86:19 ammonia in them making the planet warmer
86:22 we could also start planting trees we'd
86:24 probably need some Earth soil to do that
86:26 or we'd have to modify mars' soil to be
86:29 similar to ours sooner rather than later
86:31 the atmosphere would be close to the one
86:33 we have on Earth we'd be able to breathe
86:36 too because of the trees then we can
86:39 melt Mars's polar ice caps and voila
86:42 water the problem is the solar winds and
86:45 sun explosions that might strip it of an
86:47 atmosphere just as quickly as we can
86:49 create one if not faster it has no
86:52 magnetosphere either which means it
86:55 can't protect us from radiation so
86:57 long-term Mars wouldn't be a good choice
87:00 maybe out there in the vastness that is
87:03 space there is a perfect Planet waiting
87:05 for
87:09 us we'll start with one of the most
87:11 recent and shocking discoveries of 2020
87:14 perhaps our solar system has life beyond
87:22 Earth this is Venus the second planet
87:25 from the sun and the sister of our home
87:29 planet it's called so because it has a
87:32 similar size and mass but the conditions
87:34 on it are simply terrible the
87:36 temperature on its surface reaches 890
87:39 de fight because of the Greenhouse
87:41 Effect and the atmospheric pressure on
87:44 it is as strong as if you were 3,000 ft
87:47 underwater but in this hostile World
87:50 there can actually be life for many
87:52 years there have been discussions on
87:54 this subject in 2007 scientists
87:57 discovered there once had been an ocean
87:59 on Venus that is in the distant past
88:02 there could have been some form of
88:05 life but in the fall of 2020 there was
88:08 an epic argument in which scientists
88:10 tried to find out whether life on Venus
88:13 exists right now in September the
88:16 discovery of a new life marker on Venus
88:19 was announced the alma telescope in the
88:22 atakama desert found found phosphine gas
88:25 above the planet and the amount of this
88:28 gas suggested that it may have been
88:30 produced by certain
88:33 microorganisms but already in October
88:35 the data was analyzed again and the new
88:38 results indicate it was an
88:40 error so today we consider Venus to be
88:43 uninhabited once more but who knows
88:46 maybe soon we'll get new data and new
88:49 disputes will arise in scientific
88:52 circles and while some scientists are
88:54 scratching their heads and still
88:56 concentrating on Venus others have
88:58 looked into distant space and discovered
89:01 24 planets on which life can exist and
89:04 on all of them living conditions are
89:06 much better than on Earth such planets
89:09 are called super habitable these super
89:12 planets must be 1.3 times larger than
89:15 the earth and twice as massive thus they
89:18 will have stronger gravity and as a
89:20 consequence a denser and warmer
89:23 atmosphere so the climate on
89:25 superhabitable planets must be similar
89:27 to the tropical climate on Earth this
89:30 will ensure the maximum diversity of
89:32 living
89:34 organisms the host star of such a planet
89:37 must be a red dwarf they're much smaller
89:40 than the Sun and not so bright but their
89:43 lifespan can reach 70 billion
89:46 years for comparison the lifespan of the
89:49 sun is seven times shorter and it's
89:51 already passed half of it slow slow and
89:54 steady wins the race it will give enough
89:56 time for potential life to develop and
89:59 evolve and here's a suitable planet for
90:02 the title of superh habitable Kepler
90:06 1649c in 2020 it was named the most
90:10 similar planet to Earth it's only 6%
90:13 larger than our home World it orbits a
90:15 red dwarf a quarter the size of our sun
90:18 the planet is in the habitable zone of
90:20 the star and makes a complete circle
90:22 around it in 19 18.5 days the climate on
90:27 Kepler remains a mystery it's known to
90:29 receive about 75% of the light we get
90:32 from the Sun so the temperature on its
90:34 surface may be close to Earth's but we
90:37 still don't know the composition of the
90:39 atmosphere and other necessary
90:41 conditions for life to appear
90:43 there the next Discovery is one of the
90:45 most amazing spectacles ever seen by
90:48 Humanity it's the Collision of a star
90:51 with a black hole in September 20 2019
90:55 scientists began watching how for 6
90:57 months a sunlike star was being
91:00 spaghettified light from this event
91:02 traveled 215 million light years and we
91:06 saw a star about 860,000 Mi wide slurped
91:10 up by a black
91:12 hole this black disc is so heavy that it
91:15 has incredibly strong gravity nothing
91:18 can leave its gravitational field and
91:20 now we see a star slowly approaching it
91:23 first first the glowing light layers of
91:25 the star begin to stretch towards the
91:27 black hole it looks as if the star is
91:30 simply unrolling like a ball of
91:32 thread then we see this hot plasma
91:35 lingering at the edges of the black hole
91:37 and it may seem these particles are now
91:39 orbiting it but it's just an illusion
91:42 this ring of light is called The Event
91:45 Horizon the black hole curves not only
91:48 space but time as well this close to it
91:51 time slows down to the Observer it looks
91:55 as if the light near the edge of the
91:56 black disc has almost stopped but in
91:59 fact it has long been absorbed by the
92:01 dark
92:02 abyss when a black hole eats a certain
92:05 amount of star material it starts
92:08 spitting it out powerful beams of energy
92:11 are ejected at speeds of over 6,000
92:14 m/s this is the light that attracted
92:17 scientists attention in the end the
92:19 black hole has completely absorbed about
92:22 half of the star and spit out the other
92:25 half into space and even though we
92:27 watched this process for only a couple
92:29 of minutes it was happening for 6
92:33 months and here is one of the youngest
92:36 planetary systems that Humanity has ever
92:38 observed Au
92:40 microscopi it's so young there's still a
92:43 disc around it from the debris this
92:45 system was made of but this time we
92:47 don't even hope to find life here the
92:50 host star of this exoplanet continually
92:53 emits radiation flares that would wipe
92:55 out any form of life from the planet's
92:59 surface the planet that orbits this
93:01 dangerous star is called Au mckb and
93:05 it's just a newborn baby by astronomical
93:07 standards it's so close to its star that
93:10 it makes a complete circle around it in
93:13 8.5 days the age of this planet is only
93:16 12 million years so at the time Au MCB
93:20 was born mastadons walked on the surface
93:23 of our planet
93:24 and Meadows and savanas were covering
93:26 the Earth's face so you and I can
93:28 consider ourselves oldtimers because the
93:31 age of the Earth is almost 4.5 billion
93:36 years the next Discovery took place in
93:38 early 2020 and it's very similar to a
93:41 landscape from Science Fiction it's a
93:44 planet with two suns well more precisely
93:47 it doesn't orbit around a single star as
93:49 we are used to in our solar system but
93:52 around a binary star system toi
93:57 1338 the first big star is like the sun
94:01 the other is a red dwarf which is three
94:03 times smaller these Stars completely
94:06 Circle each other in a little over 14
94:08 days the planet that orbits these stars
94:11 is the size of Saturn which is much
94:13 larger than the earth although the
94:15 sunsets and sunrises there look
94:17 incredibly beautiful this planet is
94:20 unlikely to be suitable for any form of
94:22 life it's outside the habitable zone of
94:25 its host Stars so it probably doesn't
94:28 have liquid
94:31 water mysterious radio signals from
94:33 outer space have also been received in
94:36 2020 we're talking about fast radio
94:39 bursts scientists recorded such signals
94:42 before but recently they have managed to
94:44 prove that they are repeated after a
94:46 certain period of time the new data have
94:50 forced the scientists to come up with a
94:52 very bold theory that their Source may
94:54 be a
94:56 magnetar a magnetar is a neutron star
94:59 that is small and has a huge mass
95:02 compared to ordinary stars like the Sun
95:04 but they have the strongest magnetic
95:06 field in the entire universe their
95:09 lifetime is very short though only 1
95:12 million
95:13 years but what baffled scientists the
95:16 most this year was discovering that the
95:18 Moon is rusting corrosion needs oxygen
95:22 and water to take place but the moon
95:24 doesn't have its own atmosphere to have
95:26 both the main Theory says the solar wind
95:29 is to blame it moves at great speed and
95:33 scrapes oxygen from the upper layers of
95:35 the Earth's atmosphere the wind
95:38 continues to carry oxygen molecules
95:40 through space and eventually they reach
95:42 the surface of the Moon and cause metal
95:45 ore to
95:47 rust by the way the signature red color
95:50 of Mars was created because of the rust
95:53 for a long long time there was an
95:54 atmosphere and water in combination with
95:57 iron on its surface it triggered a long
96:00 process of rusting which has lasted
96:02 since ancient
96:04 times another stunning Discovery was
96:07 found on the surface of the Moon with a
96:09 stratospheric telescope it's an aircraft
96:12 that carries a telescope the plane
96:14 raises it to an altitude of 8 m and this
96:17 allows it to have a picture quality
96:19 comparable to that of space telescopes
96:22 and with the help of such an usual
96:24 Observatory scientists were able to find
96:26 water on the surface of the Moon water
96:29 molecules were found in one of the
96:31 largest craters on the visible side of
96:33 the satellite but the number of water
96:35 molecules is still extremely small there
96:38 the Sahara Desert has about 100 times
96:41 more water than the surface of the
96:48 Moon among all the planets of the solar
96:50 system our Earth is unique since it's
96:53 the only one that has developed life but
96:56 what if we got a competitor what if a
96:58 second Earth appeared out of nowhere
97:01 then there would be two different
97:02 scenarios the first is the destruction
97:05 of both planets the second has an
97:07 unexpected but pretty logical ending but
97:10 let's start with the catastrophic
97:12 scenario the second Earth with the same
97:14 conditions could only exist if it
97:16 received absolutely the same amount of
97:18 sunlight as our planet the orbit that
97:21 our Earth follows is perfect for getting
97:23 the necessary amount of solar heat if we
97:25 were a little further away the entire
97:28 surface of our planet would resemble
97:30 Antarctica and if Earth were a little
97:32 closer to the Sun we'd all live in a
97:34 huge desert inhabited by very few living
97:37 beings so for the second Earth to be
97:40 identical to ours it would need to
97:42 follow the orbit of our
97:44 planet two massive objects can exist
97:47 close to each other the union of Earth
97:50 and the moon is a great example but if
97:52 the second object was as heavy and huge
97:55 as our planet there wouldn't be enough
97:57 space for both of them the gravity of
98:00 Two Earths would be a huge problem the
98:02 Two Worlds would Collide because they
98:05 would be pulled toward each other this
98:07 process would last for hundreds of
98:08 millions of years and in the end the two
98:11 planets would transform into one giant
98:14 world and their remnants would be flying
98:16 around the newly formed Planet
98:18 resembling the rings around Saturn or
98:22 one of the planets would push the other
98:23 out of its orbit in this case one of the
98:26 earths would hurdle toward the Sun and
98:28 burn like a match in its atmosphere it's
98:31 also important to remember that Earth is
98:33 moving at a speed of 67,000 mph at all
98:36 times this is more than 80 times faster
98:39 than the speed of sound and now imagine
98:42 two huge planets that are flying toward
98:44 each other at such a speed even a
98:46 microscopic organism living in the mouth
98:48 of a volcano wouldn't stand a chance to
98:50 survive the Collision Of Two Earths even
98:53 the moon would be Torn to Pieces by the
98:55 blast wave but let's imagine that
98:58 Earth's twin is following another orbit
99:00 somewhere between Mars and Earth even in
99:03 this situation people's lives would
99:05 change Forever by the way the theory
99:08 that Earth might have a twin appeared
99:10 long ago scientists of the past believed
99:13 that the second planet could be hiding
99:15 on the opposite side of the sun thanks
99:17 to Modern Technologies and astronomy we
99:19 know this Theory isn't true otherwise
99:22 our telescope sces and other equipment
99:24 would have already caught some signals
99:26 from this planet scientists study space
99:29 objects thousands of light years away
99:30 from us so they would definitely notice
99:33 another world in the neighborhood but
99:35 anyway let's imagine that the second
99:37 Earth does exist and we've discovered it
99:39 recently the entire field of astronomy
99:42 and astrophysics will immediately
99:44 receive hundreds of billions of dollars
99:46 in funding the study of Earth's twin
99:49 will become a priority goal for people
99:51 experts will put forward hundreds of
99:53 hypothesis about what the second earth
99:55 looks like and what's happening there
99:57 the planet is almost at the same
99:59 distance from the Sun as we are this
100:01 means the weather must be the same there
100:04 soon scientists find out that Earth's
100:06 doppelganger has liquid water and
100:08 continents but they aren't like ours
100:11 their shapes and location are different
100:13 most likely life exists there too but
100:16 what is its origin there's a hypothesis
100:19 that life on our planet appeared thanks
100:21 to amino acids brought here by a
100:23 meteorite it's highly improbable that
100:26 the same thing happened to another world
100:28 life most likely emerged there in a
100:30 completely different way perhaps the
100:33 fish didn't get out of the water on that
100:35 planet and the first intelligent
100:37 creatures appeared in the ocean these
100:39 could be amphibians with scales and fins
100:42 or octopus-like Monsters with huge
100:44 tentacles fish on the second Earth could
100:46 have come out of the water and grown
100:48 limbs but what if they didn't like
100:50 walking on the ground then this world
100:53 might be inhabited by intelligent bird
100:55 people or life could have originated
100:58 deep in the soil then Evolution would
101:01 create humanoid moles or highly
101:03 developed
101:04 worms to find out for sure scientists
101:07 send a Rover there a similar Mission to
101:10 Mars was a success so there shouldn't be
101:12 any problems with this one people on
101:15 Earth are waiting what will the Rover
101:17 find on the other side it will take
101:19 several years for the ship to get there
101:23 strangely 2 days after the launch it
101:26 returns but wait this is not our space
101:29 probe all this time the inhabitants of
101:32 the second Earth have been watching our
101:34 planet too at one point they also sent a
101:37 probe it's made of the same materials as
101:39 ours it has a camera and a recording
101:42 device but people are worried because
101:44 the Rover looks similar to a mechanical
101:47 spider can it be that giant tarantulas
101:50 live in that world scientists understand
101:53 that that we need to communicate we send
101:55 our guests a radio signal with some
101:57 information about our civilization they
101:59 catch this message and send their own it
102:02 contains strange symbols that resemble
102:04 scratches linguists all over the world
102:07 are trying to decipher it meanwhile
102:09 astronomers send the guests a recording
102:11 of human speech a few days later our
102:14 satellites catch a message from our
102:16 space neighbors with their voices
102:18 scientists are about to play the
102:20 recording the whole world is listening
102:22 with baited breath
102:23 and it's a growl a terrible an
102:27 absolutely incomprehensible growl it has
102:30 pauses and an unusual Rhythm but it's
102:33 nothing resembling human speech the
102:36 whole planet is panicking all countries
102:38 are preparing for an invasion the most
102:40 important thing now is to build Shields
102:42 to protect the planet no one can decrypt
102:45 the message it's possible that our
102:47 neighbors can't understand us either
102:49 people make a last attempt to establish
102:51 some contact we send a video to explain
102:54 to our guests with the help of gestures
102:56 and signs that we only want peace and
102:58 collaboration the answer doesn't take
103:00 long to wait our satellite receives
103:03 their video file scientists play back
103:06 the recording and it's shocking we see
103:09 dinosaurs in robotic suits life on the
103:12 second Earth has been developing in the
103:14 same way as on our planet but the
103:17 infamous colossal meteorite didn't fall
103:19 there over millions of years of
103:21 evolution dinosaurs have have become
103:24 sensient in the video they're growling
103:27 and pointing with their claws at the
103:28 picture of our Earth then they start
103:31 growling even more loudly and is it
103:33 laughter the recording ends people
103:36 consider this the announcement of the
103:39 invasion several years have passed
103:41 during this time scientists have
103:43 exchanged messages with Dinosaurs
103:45 several times and it seems we're
103:47 beginning to understand them it turns
103:49 out that the reptiles also want peace
103:52 they say that their planet was once
103:54 inhabited by humanoids similar to humans
103:56 but a massive flood wiped them away
103:59 dinosaurs managed to survive and evolve
104:02 into intelligent beings it will take
104:04 many years before people set foot on
104:06 their planet and when this happens
104:09 Humanity will feel relieved realizing
104:11 that we're not alone but what if there
104:13 was no intelligent life on the second
104:15 Earth people would also be happy we
104:18 would know that we'd always have another
104:20 home perhaps we'd start exploring
104:23 Earth's twin right away or begin mining
104:25 its resources to replenish ours in any
104:28 case our lives wouldn't change
104:30 immediately because that land would be
104:32 too far away from our planet dozens of
104:34 generations would pass before people
104:36 begin settling on the second Earth our
104:39 homeland Planet would be losing more and
104:41 more resources so everyone would want to
104:43 move to a new world in the beginning
104:45 only the richest would be able to do it
104:48 but with time space travel would become
104:50 cheaper people would probably invest a
104:52 lot of of money to build a paradise on
104:54 the second Earth if this happened we'd
104:57 be visiting this world during our
104:58 vacation to breathe fresh air and enjoy
105:01 nature in any case the human population
105:04 would grow this means that sooner or
105:06 later the second Earth would become as
105:08 loaded as the first one and then people
105:11 would start searching for a new home
105:13 Among the Stars by the way if any life
105:16 exists on a planet similar to ours it's
105:18 likely to look like octopuses there's
105:21 even a theory that o puses came to Earth
105:24 from some other world any animal has
105:26 several evolutionary stages of
105:28 development for example elephants and
105:30 mammoths descended from one common
105:32 ancestor 5 to 6 million years ago
105:35 looking even further almost all mammals
105:37 evolved from one ancestor they shared
105:39 with reptiles each species has been
105:42 changing over millions of years but not
105:45 octopuses they suddenly appeared on a
105:47 family tree from the point of view of
105:49 evolution squids would have to evolve
105:51 into octopuses Millions of years from
105:53 now but look they're already here
105:57 besides octopuses are incredibly smart
106:00 their genetic code is much more diverse
106:02 than the human one they may be visitors
106:04 from another planet that is similar to
106:06 ours but of course this is only a
106:09 hypothesis hop on I've prepared a tour
106:12 around Earth's fellow planets let's
106:14 start with Mercury the smallest planet
106:16 in the solar system during the day the
106:19 temperature on the surface of this
106:20 planet can reach 800° f and during the
106:24 night it can drop to - 290° F the
106:27 temperatures here are so extreme because
106:29 the planet has no atmosphere instead of
106:32 it mercury has a thin exosphere that's
106:34 one of the reasons why Mercury is not
106:37 habitable the temperatures and solar
106:39 radiation are too extreme for any
106:41 organism to survive there now let's
106:44 imagine there's a way to live on Mercury
106:46 then what would life there look like
106:49 Mercury surface resembles that of the
106:50 Moon Over time meteorite left lots of
106:53 marks on it unlike the moon's surface
106:55 Mercury is grayish
106:57 Brown now look up the sun on Mercury
107:00 would appear almost three times as large
107:02 as it does on Earth the sunlight would
107:05 be almost seven times brighter I wonder
107:07 what type of sunglasses people would
107:09 wear if we lived there can life appear
107:11 on this planet in the future don't get
107:13 your hopes up it's very
107:15 unlikely now how about landing on Venus
107:19 you might think the hottest planet in
107:21 our solar system is mercury since it's
107:23 the closest to the Sun but in reality
107:26 this title goes to Venus what is it that
107:29 makes Venus boil the biggest reason is
107:32 its atmosphere it's made up almost
107:34 entirely of carbon dioxide the
107:36 atmosphere is so thick that it leads to
107:38 the planet warming up non-stop basically
107:41 the gases in the atmosphere prevent
107:43 thermal radiation from leaving Venus so
107:46 the planet simply can't cool down the
107:48 water on its surface constantly turns
107:50 into vapor if the surface of Venus was
107:53 food then its atmosphere would be the
107:55 microwave that's why the temperatures in
107:57 this world can go up to
108:00 87° fhe what would it be like to live on
108:03 Venus on Earth seasons change because of
108:06 the planet's tilt but Venus doesn't
108:08 experience any significant changes
108:11 throughout the year things are pretty
108:13 constant at night and during the day too
108:15 and what about the view of the sky the
108:18 clouds on Venus appear yellow or bright
108:20 white they're mostly made of poisonous
108:23 sulfuric acid but then why does Venus
108:25 appear reddish orange when you look at
108:27 it from Earth talking about the true
108:29 colors of planets can be a tricky
108:31 business the Hue of a space body might
108:33 be different when you look at it from
108:35 another planet if we traveled all the
108:37 way to Venus a reddish brown surface
108:39 would welcome us the molecules of carbon
108:42 dioxide and sulfuric acid block sunlight
108:45 coming into Venus's surface hence the
108:47 reddish orange color of the planet oh
108:50 and did you know that Venus is often
108:52 called Earth's twin both planets are
108:55 nearly equal in size both have
108:58 relatively young surfaces and thick
109:00 atmospheres with clouds plus the orbit
109:02 of Venus is also the closest to Earth
109:05 that might raise a question about the
109:07 possibility of Life on Venus I'm sorry
109:09 to break the news but nope Venus is not
109:13 habitable the next destination is Mars
109:17 unlike Venus Mars has Seasons due to the
109:19 planet's tilt on its axis it also has a
109:22 the secondary seasonal effect caused by
109:24 its highly elliptical orbit the southern
109:27 hemisphere has colder Winters and hotter
109:29 Summers than those in the northern
109:31 hemisphere the average temperature on
109:33 Mars is 80°
109:36 F but temperatures can also range from
109:38 the poles to the equator and they can
109:41 change very dramatically within a single
109:43 week still not that bad compared to the
109:46 previous two planets huh is Mars
109:48 habitable the number one thing a living
109:51 organism should worry about out here is
109:53 space radiation Earth has a magnetic
109:56 field and a thick atmosphere to protect
109:58 its surface from radiation Mars has
110:00 neither the planet's gravity is 1/3 of
110:04 Earth's so weaker gravity and a thinner
110:07 atmosphere make it harder for any living
110:09 being to survive on the red planet in
110:12 2013 NASA reported an ancient freshwater
110:16 lake that could have been a hospitable
110:18 environment for microbial life this is
110:21 evidenced now that liquid water once
110:23 flowed on Mars This confirmation
110:26 suggests that Mars could have had the
110:28 necessary environment to support life
110:30 but what happened to the water on Mars
110:33 the most popular explanation is that the
110:35 planet's atmosphere became too thin and
110:37 cold to keep liquid water on Mars's
110:40 surface The Disappearance of water might
110:43 also be related to the loss of early
110:45 magnetic fields or the reason might be
110:48 the red planet's size Mars is probably
110:50 too small to keep water so for now Mars
110:54 is not habitable but you know scientists
110:57 keep sending missions to Mars maybe
110:59 they'll find some new information let's
111:01 wait and
111:02 see now Jupiter have you ever wondered
111:05 what it might be like to live on the
111:07 biggest planet in our solar system
111:09 Jupiter's environment is an unlikely
111:11 place to support life the temperatures
111:14 on this planet and its composition are
111:16 too extreme for any organisms to appear
111:19 there Jupiter has layers of gas mostly
111:22 hydrogen and helium these gases fill the
111:25 entire planet quite literally there is
111:28 no solid surface on the planet gases go
111:31 all the way to the core below the
111:33 surface they become liquid and turn into
111:35 plasma because the atmospheric pressure
111:37 there is way more intense than any place
111:40 on Earth to put it into perspective an
111:43 organism on Jupiter has to resist 1,00
111:46 times more atmospheric pressure than it
111:48 would on Earth can a living being
111:50 survive in such conditions un likely
111:53 Jupiter is completely uninhabitable but
111:55 hey have you heard that its Moon Europa
111:58 might be a possible habitable zone
112:00 change of scenery Saturn it's the second
112:03 largest planet in our solar system like
112:06 Jupiter Saturn is a gas giant ball
112:09 mainly consisting of hydrogen and helium
112:12 what about temperatures on Saturn it's
112:14 freezing plus there are extremely
112:17 powerful winds there the winds in
112:19 Saturn's upper atmosphere reach the
112:21 speed of 1,000 600 ft per second let's
112:25 compare them to storms on Earth to have
112:27 a better understanding the strongest
112:29 hurricane ever recorded on Earth was
112:31 moving at 350 ft per second so the
112:35 answer to the question is there life on
112:37 Saturn seems pretty obvious Life as we
112:40 understand it doesn't exist there the
112:43 next stop is Uranus one of the largest
112:46 ice giants Uranus's atmosphere is
112:49 dominated by ice but it's not the only
112:51 reason that causes the planet's blue
112:53 color it's also the methane in the
112:55 atmosphere it absorbs red light and
112:57 reflects blue the same goes for Neptune
113:01 Uranus is the coldest planet in the
113:02 solar system the temperatures there can
113:05 be as low
113:07 as371 de
113:09 fenhe life on earth needs sunlight to
113:12 get energy but there's nothing on Uranus
113:14 that can produce any energy for life
113:16 forms to thrive the bottom line is
113:19 Uranus doesn't have the environment to
113:21 sustain life
113:23 heading for Neptune the second ice giant
113:26 what is there on the planet furthest
113:28 from the Sun obviously it's incredibly
113:30 chilly there's neither a source of
113:32 energy that bacterial life can exploit
113:35 nor a source of liquid water currently
113:37 scientists believe it's unlikely to find
113:40 life on Neptune because of such
113:41 unfriendly conditions so what makes our
113:45 planet so livable and I'm not just
113:47 talking about human life I mean any
113:49 living organisms even microbes life
113:52 requires very special conditions to
113:54 exist all living beings need some sort
113:57 of food water and the right temperature
113:59 to develop the atmosphere is a vital
114:01 element humans for instance need oxygen
114:04 to breathe and they can only survive in
114:06 temperatures that aren't extremely hot
114:08 or cold another thing is gravity all the
114:12 other planets I've mentioned don't have
114:14 exactly the same conditions as Earth
114:17 life there would probably be different
114:18 than what we have here all living beings
114:21 on earth have a adapted to our
114:23 atmosphere and life forms elsewhere
114:26 would need to be able to survive in that
114:28 planet's conditions is that Earth you
114:31 can see at a distance right just look at
114:34 it floating in space hanging out with
114:36 its Planet buddies you spot orange red
114:39 Mars and Jupiter with its asteroid belt
114:43 even tiny Pluto is
114:45 there all these planets keep their
114:47 distance from each other moving along in
114:49 their own orbits they're not very social
114:52 you see but that's a good thing it would
114:55 cause nothing but trouble if they
114:56 started to bump into each
114:58 other but even though there are others
115:01 Earth is the only planet we know that
115:03 has life and we've even figured out why
115:08 it's because it was lucky enough to
115:10 appear in the best spot in our solar
115:12 system in the goldilock
115:15 zone scientists say the key ingredient
115:17 for life is water but well there's water
115:21 on Mercury this planet has deposits of
115:24 water ice at its South and North Poles
115:27 but only because those places never see
115:29 the light everywhere else water simply
115:33 evaporates from the surface of the
115:34 planet Mercury is way too close to the
115:38 Sun Pluto has some water too astronomers
115:42 even think the dwarf planet might be up
115:45 to 30% water but it's frozen unlike
115:49 Mercury Pluto's too far away from the
115:51 Sun which is why all its water is in the
115:54 form of
115:55 ice but Earth hovers in a perfect spot
115:59 called the habitable zone it has the
116:01 right temperature for the water to
116:03 remain liquid and for all forms of life
116:05 to flourish but what if Earth was the
116:08 only planet in the solar system no Mars
116:11 no Jupiter no Mercury no Venus things
116:15 might have turned out a little different
116:17 than what we're used to remember that
116:19 massive asteroid that hit the Earth
116:21 around 66 million years ago well without
116:25 Jupiter and its asteroid belt our planet
116:28 would be constantly hit by meteorites
116:30 and asteroids and some of them would be
116:33 just as big as the one that caused all
116:35 that sorrow to the
116:36 dinosaurs these Rocky fellas would be
116:39 roaming around in space with no one and
116:42 nothing to stop them and if Earth was
116:45 the only planet out there it would also
116:47 be their only
116:49 target but that's not all look at all
116:52 this huge space Earth would have all to
116:54 itself it means our planet would have an
116:57 opportunity to travel a bit it could
117:00 even choose to leave the goldilock Zone
117:03 but then would life on the planet still
117:05 be the same so let's say earth started
117:08 drifting away from the Sun then it'd
117:11 soon get too cold on the planet picture
117:14 a place where the sun doesn't shine
117:16 anymore dark cold covered in ice and
117:20 snow all year round that would be our
117:23 Earth if it traveled further from the
117:25 Sun if this happened our cities would
117:28 start to look very
117:30 different right now Earth is full of
117:32 Life come to any park and you'll see
117:35 green trees and grass everywhere there
117:37 will be people walking sitting on the
117:39 benches enjoying the sun you'll
117:42 definitely spot someone playing soccer
117:44 or frisbee on the parks Lawns there will
117:47 be people resting on their blankets
117:48 soaking up the Sun a few people will be
117:51 reading their books
117:52 looking relaxed and happy back in space
117:56 you see Earth again the planet is still
117:58 in its favorite spot that's why life is
118:01 so beautiful down there but wait is it
118:05 moving our planet is definitely further
118:08 from the Sun now has it changed things
118:10 for Earth it actually looks a bit Bluer
118:14 now down there Famous Golden California
118:17 is not so golden anymore it's gloomy and
118:20 dark much like like all other places on
118:23 Earth New York is covered in ice even in
118:27 the hottest places the temperatures are
118:29 now below freezing including tropical
118:32 destinations like the
118:34 Bahamas after a while liquid water turns
118:37 into ice the oceans now look like giant
118:40 skating ranks except there's no one to
118:43 skate there since the planet has become
118:45 way too cold to support
118:48 life okay then what if instead of
118:51 drifting further away from the sun earth
118:53 moved closer with people still aboard
118:57 who the temperatures here are crazy too
119:00 hot to handle the climate would be
119:02 getting hotter and hotter natural
119:05 disasters would start to occur more
119:06 often hurricanes and floods would be a
119:09 common thing on earth now and pretty
119:11 soon the planet would get too hot for
119:14 people to handle particles from the Sun
119:17 would become a serious threat the
119:19 atmosphere would be struggling to
119:20 protect Earth from solar radiation but
119:23 this Shield would be growing weaker
119:26 liquid water would be nowhere to be
119:28 found anymore maybe only in underground
119:31 deposits Earth would look a bit like
119:33 Mars all Rocky and Barren the
119:36 Mississippi River would dry up and leave
119:38 behind a huge Canyon all the oceans
119:41 would be gone too at the moment the
119:44 Mariana Trench is the deepest known
119:46 place on Earth it's incredibly hard to
119:49 reach its bottom because of the immense
119:51 water pressure there
119:52 but without water trips to the deepest
119:54 spot on Earth would be possible it would
119:57 help people uncover some more of Earth's
119:59 Secrets if people still lived on the dry
120:02 and scorching hot planet that is in
120:04 other words if someone was to explore
120:07 Earth after the planet had moved closer
120:09 to the Sun everything would be
120:11 completely different but what if Earth
120:14 didn't move at all and everything
120:16 remained the same the only difference
120:19 there would be no other planets around
120:20 us it would change the way people
120:23 explore space sure there would still be
120:25 navigation communication and weather
120:28 satellites and maybe space telescopes
120:31 but there wouldn't be any other space
120:33 objects close enough for people to send
120:35 missions there this would affect the
120:38 future too if people had no desire or
120:41 opportunity to go to space they would
120:43 invest in their home planet they would
120:45 build Sky cities instead of looking for
120:48 other planets to
120:50 colonize these days if you get a
120:52 state-of-the-art telescope you'll see
120:54 distant stars and other planets the
120:57 better the telescope the more detail
120:59 there is for you to see but with no
121:01 other planets out there the picture of
121:04 space wouldn't be so exciting Stars
121:06 would still be visible and you might
121:08 even spot a meteorite or two and you'd
121:11 definitely see the moon but that's about
121:14 it space agencies would mostly be
121:17 focused on keeping Earth secure mainly
121:20 because asteroids would become fre qu
121:22 visitors to protect the planet
121:24 scientists would have to figure out ways
121:26 to get rid of them like a massive laser
121:29 beam when turned on it could go all the
121:32 way to the moon and even
121:34 further instead of building Rockets to
121:37 explore space SpaceX and NASA would be
121:40 in the asteroid clearing
121:42 business people wouldn't even think of
121:44 trying to contact other civilizations if
121:47 there were no planets similar to Earth
121:49 they would consider it a wasted effort
121:52 this means no radio signals being
121:54 constantly sent out to space a curious
121:58 fact in February of 2008 the beetle song
122:01 Across the Universe was beamed into deep
122:04 space it was done to celebrate both the
122:07 song's 40th anniversary and NASA's 50th
122:11 anniversary in the 70s people also sent
122:14 a radio signal out into space it
122:17 contains some basic information about
122:19 humans and the solar system but it was
122:22 more a feat of strength for technology
122:25 than an attempt to contact any alien
122:27 buddies we might have with no planets
122:31 around the world of sci-fi would change
122:33 too there would be no more movies about
122:36 deep space exploration no massive
122:38 spaceships and Rockets would appear on
122:40 the big screen and since there would be
122:42 no expeditions to other planets no
122:45 Rovers would be sent to space to look
122:47 for signs of life and explore new worlds
122:50 like what the Rovers on Mars are doing
122:52 right
122:53 now people would concentrate more on
122:55 their own planet for example they would
122:58 begin to explore its insides new
123:01 technologies would allow us to dig much
123:03 much deeper all the way through Earth's
123:06 crust and further and doesn't a trip to
123:08 the planet's core sound
123:11 exciting instead of astronauts there
123:13 would be explorers of the deep
123:15 underground new Drilling Technologies
123:18 would be invented to make the digging
123:19 process more effective there would be
123:22 new types of vehicles they would be
123:24 created to drill and protect explorers
123:26 from the enormous underground pressure
123:29 while exploring the world under the
123:31 planet surface people would likely find
123:34 absolutely new life forms those would be
123:37 mysterious creatures that evolved to
123:39 survive in the dark in extreme
123:41 temperatures and with barely any food it
123:44 certainly helped people understand more
123:46 about their home planet