0:02 the earth isn't flat this is something
0:05 we've known now for thousands of years
0:07 aristotle approved it empirically by
0:08 traveling to egypt and witnessing new
0:10 constellations of stars from the other
0:12 side of the globe
0:13 after eradostinis used no more than a
0:15 stick and light from the sun to
0:16 calculate the earth's circumference in
0:19 the time of ancient greece
0:21 yet throughout history groups of people
0:23 have been constantly re-emerging to push
0:25 the notion that the earth our tiny blue
0:27 planet floating in space
0:29 is in fact flat
0:31 the idea first resurfaced in recent
0:34 history in the 1800s then a society of
0:36 flat earthers was set up in the 1950s
0:38 transforming the group from conspiracy
0:39 theorists to an organization with
0:41 thousands of members
0:43 as the internet began to grow in
0:46 popularity so did this organization
0:48 in no time flat earthers began growing
0:50 in number attracting some pretty well
0:52 known members of society these included
0:54 movie stars rappers and professional athletes
0:58 flat earth theorists have different
1:00 models supporting their idea perhaps the
1:02 most popular is that the arctic or the
1:04 north pole is at the center of the
1:06 planet while antarctica surrounds its
1:09 edges with thick and long walls of ice
1:11 a pancake shaped earth floating in space
1:13 as the sun and other planets rotate
1:16 above it like a celestial carousel
1:17 with all the evidence in the world to
1:20 prove that this isn't the case why do
1:21 thousands of people still believe that
1:23 the earth is flat including one-third of
1:25 american millennials
1:27 the truth is a combination of a lot of
1:28 different things that we really don't
1:30 have time to go into in today's video
1:32 but with all the popularity this topic gets
1:33 gets
1:34 it's only right that we ponder the concept
1:36 concept
1:38 what if the earth was actually flat how
1:40 different would our world be from what
1:48 first if the earth was flat we'd all be
1:49 dead because gravity
1:50 gravity
1:52 our understanding of gravity has
1:53 developed throughout the years from
1:55 being a force that pulls us towards the
1:57 center of mass to being reimagined as
1:59 the curvature of space-time that sets
2:00 the course for planets to rotate around
2:02 their stars
2:04 gravity is the reason that earth and all
2:06 other planets are round
2:08 imagining a flat earth would mean that
2:10 gravity as we know it must be having no effect
2:12 effect
2:13 but let's say for the sake of argument
2:15 that gravity would still have an effect
2:17 it's unclear how gravity would behave on
2:18 a flat planet
2:20 knowing what we do suggest that it would
2:22 pull towards the center of the disc
2:24 shaped earth at its north pole or the
2:26 arctic this means that the further you
2:28 get away from the center of the disk the
2:30 stronger gravity pulls you back towards
2:31 the center
2:33 as a result trying to reach the supposed
2:34 ice walls of antarctica at the edge
2:36 would be impossible as the gravitational
2:38 pull would make it seem as if we're
2:41 climbing a hill that only gets steeper
2:43 oceans seas rivers streams and all other
2:45 water bodies would converge at the
2:47 center of the planet
2:49 rain snow and hail would also fall
2:50 towards the center while trees would
2:53 grow diagonally developing in the
2:55 opposite direction of gravity's pool
2:57 the effects of flat earth gravity
2:58 doesn't end here
3:00 as more air gets sucked into the earth's
3:02 center it creates an atmosphere that
3:03 would be lung crushing close to the
3:05 north pole and without enough oxygen to
3:07 breathe at the outer edges
3:09 earth would already be so uninhabitable
3:11 to life as we know it and it's only just
3:12 the beginning
3:14 without its spherical shape our planet
3:16 would lose its layered structure and
3:18 behave very differently earth is made up
3:20 of three layers with the densest
3:22 material sinking to the core the lighter
3:24 making of the mantle and the lightest
3:26 making up the crust
3:27 the outer core is composed of molten
3:29 iron and nickel that acts as a giant
3:32 magnet creating earth's magnetic field
3:33 it's what protects our atmosphere from
3:35 the sun's harmful solar winds and
3:37 without it our atmosphere would
3:39 dissipate our oceans would spill into
3:41 space leaving earth a lifeless barren
3:44 land similar to mars
3:45 but suppose somehow we managed to
3:47 survive all of gravity's grueling ways
3:49 to destroy us our living experience on a
3:51 dis-shaped planet would still be very different
3:52 different
3:54 flattening earth will increase its
3:56 surface area by two and a half times
3:58 this means traveling across the planet
4:00 instead of around it would take
4:02 significantly longer
4:03 it's also unlikely that satellites would
4:06 be able to orbit or more precisely hover
4:08 above a flat earth
4:10 without any satellites we'd lose access
4:12 to gps services leaving us without
4:15 navigation synchronized time or or the
4:16 ability to perform all sorts of global
4:19 financial transactions
4:20 having no satellites also means that we
4:22 won't be able to study our planet from
4:24 the atmosphere
4:26 grace the gravity recovery and climate
4:28 experiment for example was the satellite
4:29 that was launched in 2002 to take
4:31 detailed measurements of the earth and
4:33 collect data to significantly enhance
4:34 our understanding of global climate patterns
4:35 patterns
4:37 it's a mission still being carried on by
4:41 grace fo which was launched in 2018.
4:42 without such satellites our
4:44 understanding of our planet would be limited
4:45 limited
4:47 for a long time humans thought that we
4:49 were at the center of the universe it
4:52 wasn't until 1543 that polish scientist
4:54 nicolas copernicus first hypothesized
4:56 that ours is just another planet
4:58 revolving around a star
5:01 yet almost 500 years later flat earthers
5:02 still believe that we're at the center
5:04 of the universe
5:06 they propose this through two models
5:07 with the only difference between them
5:10 being how the sun rotates around us
5:12 in the first model the sun circles above
5:14 the earth and sheds its light in warmth
5:16 on certain regions like a high-powered
5:17 desk lamp
5:19 if this is how our world was we should
5:21 be able to see the sun from anywhere
5:23 across the globe even if it isn't
5:25 currently shining in that region
5:26 it would also mean that day and night as
5:29 we know it simply wouldn't exist because
5:32 if the sun doesn't rotate then it shines
5:33 on the same parts of the globe all day
5:35 long leaving some places an internal
5:38 sunshine and the rest of the planet in
5:39 utter darkness
5:41 to help account for the day cycles the
5:43 second model proposes that the sun is
5:45 rotating spherically around the earth
5:47 if this happened our entire planet would
5:49 witness daytime and nighttime
5:51 simultaneously because the whole planet
5:53 would be brightened and darkened at the
5:55 same time each day
5:57 in both of these models there would be
5:59 no time zones no seasons and no moon in
6:01 our depleted atmosphere
6:02 the view of the night sky would be the
6:04 same from anywhere in the world and our
6:05 view into space would be limited to the
6:08 patch of the galaxy directly above us
6:11 because again without any rotation
6:13 we'll be staring at the same thing every
6:15 single time we look up
6:18 it gets worse if the sun is as big as it
6:19 currently is
6:21 it would burn the planet
6:22 on the other hand if it was as small as
6:24 these theories suggest then earth would
6:26 freeze because sunlight wouldn't be able
6:29 to reach its increased surface area
6:30 it seems that all iterations of the
6:32 flatter theory end up with the
6:33 destruction of our planet and everything
6:34 in it
6:36 shouldn't the fact that we're alive then
6:39 be proof enough that the earth is round
6:42 in theory it should but facts don't
6:44 change minds i made an entire video
6:45 about this if you want to check it out
6:48 link is in the description but the truth
6:49 is that humans have known for a very
6:52 long time that the earth is in fact round
6:53 round
6:56 around 500 bce pythagoras first proposed
6:58 that the earth is spherical while his
7:00 findings were not based on any physical evidence
7:00 evidence
7:03 he believed along with many greeks after
7:05 him that a spherical shape simply made
7:07 the most sense
7:09 over a century later aristotle was the
7:10 first to provide empirical evidence of
7:12 earth's surrounding shape listing many
7:14 arguments such as ship's disappearing
7:15 hall first when they sail over the horizon
7:16 horizon
7:18 earth found shadow on the moon during a
7:20 lunar eclipse and different
7:21 constellations being visible at
7:23 different latitudes
7:24 the greeks believed so much that our
7:26 planet was round even in times with very
7:28 limited technology that they went as far
7:31 as measuring out its size
7:34 in 276 bce eratosthenes discovered that
7:37 the earth's circumference to be 40 250
7:41 to 45 900 kilometers or 25 000 to 28 000 miles
7:43 miles
7:45 simply by using the shadow of a stick to
7:47 measure the angular displacement of the
7:49 sun in two different locations
7:50 he then multiplied the angle by the
7:52 distance between the two locations and
7:54 gave us our first estimation of the size
7:56 of the planet
7:59 and the thing is he wasn't that far off
8:02 earth's actual circumference is 40 070
8:06 kilometers or 24 901 miles
8:08 if you're wondering we measured it using
8:10 an orbiting spacecraft
8:12 apart from being such an astonishing feat
8:12 feat
8:14 measuring the earth using the angular
8:17 displacement of the sun in two locations
8:19 was also another piece of evidence to
8:21 prove that the earth is spherical
8:23 on a flat plane the shadow cast by the
8:26 sun would be the same length everywhere
8:27 it's only because of the earth's
8:29 curvature that the sun can shine on one
8:31 part of the earth at one angle and on
8:32 another part of the earth at a different
8:34 angle causing one shadow to seem longer
8:36 than the other
8:38 following the greeks islamic scholars
8:39 made further advancements in the 9th
8:42 century then european navigators circled
8:44 the globe in the 16th
8:46 finally in the 20th century we sent
8:48 spacecraft satellites and probes into space
8:49 space
8:50 all of which brought back astonishing
8:53 images of our big blue planet
8:54 time and time again through different
8:56 pieces of research done by various
8:58 communities around the world who don't
9:00 agree on a lot of things
9:02 we've proven empirically mathematically
9:04 and scientifically that this little rock
9:06 we all call home
9:09 is around [Music]
9:14 [Music]
9:16 but if we're being honest it was never
9:18 really about the evidence
9:20 believing in a flat earth is a form of
9:22 science denial where people entirely
9:23 question the main premise behind
9:25 scientific ideas
9:27 science denial is usually linked to a
9:29 conspiracy mentality that makes people
9:31 susceptible to wrong ideologies about
9:32 all things science
9:34 what all these people have in common is
9:36 the denial in the scientific process and
9:38 are discussed for organized institutions
9:40 like governments and research agencies
9:42 while believing in a flat earth doesn't
9:44 seem to be as harmful as not believing
9:46 in climate change for example
9:48 conspiracy theories in general become
9:50 dangerous when they gather a large following
9:51 following
9:53 so large that they start to affect some
9:55 changes in the policies and decisions of
9:57 a society
9:59 lee mcintyre a philosopher from boston
10:01 university and an expert on science denial
10:02 denial
10:04 believes that if these misguided ideas
10:06 aren't challenged proponents of a flat
10:08 earth will start running for u.s school
10:10 boards looking to push their ideas into
10:13 the u.s education system
10:14 because conspiracy theorists are
10:16 generally highly skeptical people who
10:17 have lost their trust and authority
10:19 while we understand that facts don't
10:20 always change minds
10:22 perhaps instead of arguing the evidence
10:24 for a spherical earth a better approach
10:25 would be to help these people
10:28 reestablish their trust in science
10:30 make it about the emotion instead of the
10:32 facts because even in face of
10:34 overwhelming counter evidence
10:36 people are most likely to cling to their beliefs
10:37 beliefs
10:39 instead of patronizing flat earth
10:41 proponents science needs to take their
10:43 questions seriously and answer them
10:45 patiently and with the level of
10:47 sustained engagement
10:49 flat earthers may distrust science today
10:51 but approaching their uncertainties with
10:53 a lower level of scrutiny could help
10:55 against the spread of misinformation and
10:56 deceptive claims
10:58 be that as it may there's still a
11:00 special appeal to the flat earth theory
11:02 not because it holds any scientific
11:04 merit but simply because it allows us to
11:06 imagine how unforgiving the universe
11:08 could be if the conditions were any different
11:09 different
11:11 are planets uniquely built to sustain
11:13 millions of life forms and its spherical
11:16 shape is essential to our survival
11:17 this is the most famous image taken of
11:20 our planet it's called earthrise and it
11:21 changed our relationship with our home forever
11:22 forever
11:24 while earlier spacecraft had taken
11:27 images of earth this is the first one
11:29 taken by an awestruck astronaut holding
11:30 a camera
11:32 when william anders took this picture
11:34 from the moon's orbit in 1968 he offered
11:36 us a one-of-a-kind glimpse at the rock
11:38 we all call home in its place in the
11:40 cold dark universe
11:42 it's almost as if humanity was able to
11:43 look itself in the mirror for the first time
11:45 time
11:48 take a deeper look at this image
11:50 right now all of us are somewhere on
11:52 this little blue ball half submerged in
11:55 darkness quietly floating in empty space
11:57 we have a protective atmosphere to
11:58 shield us from the harmful rays of the
12:01 sun breathable air and oceans of water
12:03 integral to our survival
12:05 the sun gives us light and energy and
12:06 gravity keeps us rotating at a safe
12:08 distance from it
12:10 this tiny blue ball floating in the
12:12 darkness of space right now seems to be
12:13 the only place in the observable
12:15 universe with just the perfect
12:18 conditions to spawn life
12:18 so no
12:21 earth isn't flat
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