YouTube Transcript:
Alien Worlds: The Search for Earth 2.0 | Space Documentary

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can you believe it
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can you realize that we that you and I
that all of us
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actually begun
the exploration of another world
come with us
Life as We Know It
took birth some 4 billion years ago
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the emergence of the first ever cell was
a Monumental event in the history of
life on Earth
it marked the beginning of a journey
that would take billions of years to
unfold
and that would eventually lead to the
incredible diversity of species
that we see today
this first cell was a small but vital
step towards the eventual evolution of
complex organisms
it was made up of proteins the essential
building blocks of life and it had just
a handful of crucial functions that
allowed it to survive and replicate even
though it was incredibly basic in its
design this first cell was where it all
started
good
As Time passed the Earth's conditions
changed and this provided the impetus
for life to evolve and flourish in new
and exciting ways
and as the temperature of the planet
gradually cooled the atmosphere became
richer in oxygen providing the ideal
conditions for new forms of life to
emerge over time these simple organisms
evolved into more complex forms and the
diversity of life on Earth grew
exponentially
today the diversity and complexity of
life on Earth is truly staggering from
the earliest bacteria to the largest
whales each new species has brought
something unique to the table helping to
shape the world around them in countless
ways
the animal kingdom is full of
fascinating creatures with remarkable
abilities that allow them to survive in
their respective habitats bats possess
the remarkable ability to echolocate a
skill that allows them to effortlessly
navigate through the darkness and hunt
with pinpoint accuracy
cheetahs can run at mind-boggling speeds
of up to 60 miles an hour
making them one of the fastest animals
on the planet
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and then there are koalas who move at a
glacial Pace spending up to 18 hours a
day sleeping as they conserve their
precious energy
a unique strategy that allows them to
survive on a diet that is low in
calories and it's just one example of
the ingenious ways that nature has
evolved to overcome the challenges of
survival
but perhaps the most remarkable species
of All Is Us humans
unlike other animals we have the ability
to use our brains to invent and create
things that transform the world around
us
we have harnessed the power of fire
created language and built civilizations
that span the globe from the wheel to
the smartphone and even sent people to
space
humans have constantly pushed the
boundaries of what's possible
while we've made incredible discoveries
about our own world and the universe
around us a central question has
fascinated us for centuries
are we alone in this universe
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with billions or even trillions of
galaxies in the universe each with its
own unique set of stars and planetary
systems the odds of Earth being the only
planet capable of supporting life seen
vanishingly remote
the idea that life might exist beyond
Earth has captured the imaginations of
scientists philosophers and storytellers
for centuries and with each passing year
our understanding of the universe grows
bringing us even closer to answering
this age-old question
as we continue to discover more about
the cosmos we learned that there could
be countless other planets that could
potentially Harbor life
with conditions that are similar to
Earth
these planets could have a stable
environment complex geology
flowing water
and the necessary conditions to support
Life as We Know It
it's a tantalizing thought that there
could be other creatures out there
perhaps even intelligent ones who are
wondering the same thing we are
so far the universe remains silent
leaving Humanity to wonder if we are
truly alone
are we being observed
are extraterrestrials avoiding us
through the utilization of countless
telescopes on Earth and in space each
painstakingly scouring the vast expanse
of the universe for even the slightest
indication of a planet capable of
supporting life we find ourselves edging
ever nearer to an elusive answer
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every life form needs a planet to live
but how many planets are there in the
universe
one of the earliest modern day attempts
to answer this question was made by the
astronomer Frank Drake in the early
1960s using a radio telescope in Green
Bank West Virginia he set his sights on
two nearby Stars Epsilon eridani an
orange star just 10.5 light years away
and Tau seti a yellow star about
three-quarters the size and mass of our
sun
with his expertise Drake postulated that
signs of alien intelligence could
potentially be streaming bias in the
form of radio signals
he formulated an equation that sought to
estimate the number of planets with
intelligent life in our galaxy alone
through his calculations he arrived at a
conservative estimate of four thousand
such planets in the Milky Way
fast forward six decades Searchers have
checked and rechecked Epsilon eridani
taucetti and many other nearby Stars
and so far they've found no repeating
messages or anomalous signals
however with the advancement of
Technology we continue to increase our
estimation of the number of potentially
habitable planets in the known universe
today the estimate of this figure has
increased by a gazillion
it is now believed that there could be
more planets than stars in the Milky Way
galaxy with potentially at least one
planet per star
there could be up to a million billion
trillion planets in the entire universe
this mind-boggling number opens up the
possibility that there could be
countless Earth-like planets out there
with a rocky surface atmosphere and
liquid water making them Prime
candidates for the development of life
astronomers posit that when a solar
system is formed the early star produces
a strong solar wind that blows away most
of the lighter gases in the inner part
of the solar system leaving only the
denser Rocky material
this allows these materials to come
together and form small rocky planets
like Earth
on the other hand gas giants like
Jupiter and Saturn form farther out in
the solar system where the solar wind
was not strong enough to blow away the
lighter gases
this allows the gas giants to grow much
larger and accumulate large amounts of
gas and Ice resulting in their massive
size compared to Rocky inner planets
to understand what is happening on the
surface of these planets to find out if
these worlds are or can be inhabited
astronomers use their most powerful
telescopes to scrutinize the sky
the square kilometer array the largest
radio telescope in the world it boasts
the capability of a collecting area of
one square kilometer
Green Bank Observatory located in
Virginia the green Bank telescope is the
world's largest fully steerable radio
telescope and the elt currently being
built in Chile the extremely large
telescope will be the world's most
advanced telescope ever built
and in space thanks to The Cutting Edge
telescopes like the Kepler space
telescope and Tess
astronomers have discovered more than 5
000 planets outside our solar system
scientists call them exoplanets
many of them have been found that exist
within the Goldilocks zone the region
around a star where it is warm enough
for water to flow where the temperature
is just right for Life as we know it not
too hot and not too cold
many of them that lie hundreds of light
years away have been detected using the
transit method an indirect method
wherein scientists track the minuscule
dimness of the star when a planet
eclipses its light
when astronomers detect this dip in
light levels they found a new planet
highly upgraded telescopes now allow
detection if the light of the star has
been dimmed by a factor of a thousandth
by using and analyzing the spectrum of
the star's light before during and after
the transit scientists can determine how
the planet's atmosphere affects the
Starlight passing through it this
analysis provides valuable information
about the planet's composition including
what gases make up its atmosphere and
whether or not it has a rocky surface
using these astronomical methods
scientists have been able to explore and
study the chemical compositions of
numerous exoplanets in our galaxy and
Beyond
and what they have found is truly
astonishing
some exoplanets have been found to
contain high levels of heavy elements
such as carbon oxygen and nitrogen the
very elements that are essential for
Life as we know it to exist but that's
not all in recent years scientists have
also discovered a number of exoplanets
that share striking similarities to our
own planet
close your eyes
and imagine looking up at the night sky
and seeing a faint reddish star shining
back at you
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you may not know it but that star is the
home to the closest exoplanet to our own
and it's a world that could potentially
Harbor Life as We Know It
this is Proxima Centauri B the closest
exoplanet to home
Earth's twin as suggested by data
how would life adapt to such a world
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located 4.2 light years away from Earth
the Alpha Centauri system a triple star
system is home to Proxima Centauri a
tiny red dwarf star
it orbits around a pair of sun-like
stars Alpha Centauri A and B
and right there nestled in the habitable
zone of its star is Proxima Centauri B
the gem of this star system
Proxima B orbits its star at a distance
of just 4.6 million miles
this is incredibly close just five
percent of the distance between the
Earth and the Sun and even closer than
the distance between Mercury and the Sun
however since Proxima Centauri is only
one-tenth of the size of our sun
the star's habitable zone is much closer
to it
but the Goldilocks zone being so close
to the star's surface also has its
drawbacks
due to the planet's close proximity to
its star it becomes tidally locked
one side of the planet is always facing
the star
a scorching desert
while the other side is forever dark
exposed to the cold vacuum of space
this could make it difficult for life to
find a foothold
such temperature extremes on Proxima
Centauri B make it hard for life to
exist
but there may be hope
in the Twilight Zone where the light and
dark sides meet the temperature is just
right making it a potential Haven for
Life between scorched Earth and eternal
winter
it is in these conditions that life may
be able to adapt and thrive
astronomers discovered Proxima B in 2016
using the radial velocity method they
detected a tiny star wobbling slightly
in a small circle this subtle movement
was caused by the gravitational pull of
a nearby planet and upon closer
investigation they identified the planet
as Proxima Centauri B
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after careful study and Analysis of the
exoplanet it became clear that Proxima b
as it was named was strikingly similar
to Earth
in fact the planet scored an impressive
0.87 ESI which is a measure of its
similarity to Earth
this score takes into account various
factors such as the planet's size mass
temperature and density
based on these factors scientists
estimate that Proxima Centauri B is 87
Earth-like making it a promising
candidate for extraterrestrial life
but despite its high ESI score much
about the planet remains unknown
including whether or not it has an
atmosphere
the star at orbits Proxima Centauri is a
highly active Red Dwarf flare star
which means that the planet is
constantly bombarded with intense
Stellar Wind pressures
over 2 000 times greater than what Earth
experiences from the solar wind
these conditions raise the possibility
that the planet's atmosphere could have
been Stripped Away over time leaving it
Barren exposed to the harsh conditions
of space and inhospitable to life
on Proxima B where the threat of solar
flares and intense winds could be a
daily occurrence life may have found a
way to survive by taking refuge in the
depths of its oceans
on Earth we've already discovered life
that can withstand intense radiation by
utilizing specialized adaptations
Coral polyps have evolved to produce
fluorescent proteins that block
excessive sunlight effectively
neutralizing the detrimental effects of
ultraviolet light in Shallow Waters they
can glow brilliant pink and purple at
night creating a stunning spectacle
models show that it's possible with the
right conditions that Proxima B could
actually withstand such levels of
radiation
a robust and strong magnetosphere could
potentially redirect the Stellar winds
to the planet's poles creating
spectacular auroras that would be many
times greater in size and Luminosity
than those experienced on Earth
if this holds true it's possible that
life on Proxima B could resemble life
here on Earth in unexpected ways
its surface would likely be much warmer
than Earth's average temperature
creating conditions that could support
life
scientists suspect that any life forms
on the planet would likely resemble
those found here on Earth as the
principles of evolution are considered a
universal law of nature just like
gravity
evolutionary convergence is a process by
which unrelated species can evolve
similar adaptations to similar
environmental challenges meaning that
life on other planets might look
surprisingly familiar to us
the evolution of Life on any planet is a
delicate balance between beneficial and
harmful changes even on Earth where life
has flourished for billions of years the
vast majority of species that ever
existed have gone extinct however some
life forms have managed to persist and
Thrive and some have even evolved into
incredibly complex organisms flight is a
great example of this
in an environment filled with fluid-like
water one can either float if they're
lighter than the fluid or use wings to
fly aerodynamically and generate lift
for example the wings of bats birds and
insects all serve the same purpose but
they've evolved independently of each
other
similarly if two exoplanets have
identical conditions such as temperature
atmospheric pressure and access to water
it's possible that life could arise on
both planets and evolve in similar ways
to adapt to their environments so if
Proxima B supports life and there's a
high chance at least to some degree that
it may resemble life on Earth
Additionally the presence of similar
conditions on exoplanets could also lead
to the development of similar
biochemistry for example life on Earth
is based on carbon and it's possible
that life on exoplanets could also be
based on carbon if the conditions on
those planets are like those on Earth
but most carbon-based life forms like
those on earth have their own set of
limitations
carbon compounds have lower melting and
boiling points which can make it
difficult for organisms to survive in
extreme environments like the scorching
heat near a star or the freezing cold of
deep space
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so what if life on an alien planet has
adapted so well to its condition that
it's become extremely resilient and can
survive even the most extreme conditions
is it possible that life in the universe
may take on forms that are vastly
different from what we know and
understand
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close your eyes and imagine a world
where the ocean stretches across the
entire planet
a world where the water is so hot that
it could boil twice as quickly as it
does on Earth yet the water doesn't boil
away due to the intense pressure created
by the atmosphere which is almost 10
times stronger than Earth's
this is a hycian planet
k218b located about 124 light years away
from us it's a world where only the
fittest can survive
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of the thousands of exoplanets
discovered within the last 30 years this
really caught the scientists attention
on August 26 2021 scientists claimed
that they had identified a new class of
planets planets which are up to three
times the size of Earth can have a mass
8 to 10 times that of Earth scorching
temperatures up to 200 degrees Celsius
thick hydrogen atmospheres and
planet-wide oceans hundreds of miles
deep
they call them piscean worlds
k218b is one such piscean world and
scientists believe it resides in the
habitable zone of its star
such planets because of their size allow
for a much wider habitable zone compared
to earth-sized planets
this means that even if they're situated
much further from their host Sons they
could still support life
similar to Proxima b a vast majority of
these hycian planets are tidally locked
which implies that one side of the
planet always faces its host star while
the other side remains shrouded in
Perpetual Darkness offering life little
chance for survival on the Terminator
line
however
k218b distinguishes itself from the rest
as the Hubble Space Telescope has
already confirmed the presence of water
Vapors in its atmosphere this
groundbreaking discovery marks the first
time water has been detected on any
exoplanet the presence of water on K2
18b makes it a prime candidate for the
search for extraterrestrial life as it's
a crucial ingredient for the evolution
of Life as We Know It
but despite the planet's surface
temperature being a comfortable 10
degrees Celsius its hydrogen-rich
atmosphere causes the temperature and
pressure to increase as you descend
deeper into its depths at the rocky core
the pressure is expected to be thousands
of times higher than that of Earth's
surface with temperatures that can
approach a scorching 5000 degrees
Fahrenheit
these conditions make it difficult for
complex molecules to form leaving
scientists to ponder how life could
adapt to such an extreme world
while many of the Prime heisian
candidates identified by researchers are
bigger and hotter than k218b they are
believed to still have the
characteristics to host large oceans
that could support microbial life
similar to that found in some of Earth's
most extreme watery environments
it's truly fascinating to realize how
life can Thrive even in such extreme
conditions
surprisingly on Earth highly resistant
microbes such as tardigrades have
managed to withstand such harsh
conditions
tardigrades also known as water bears
for example can even manage to live
without water for up to 10 years these
organisms known as extremophiles can
survive and flourish in extreme
conditions such as high crushing
pressure acidic or alkaline conditions
and scorching temperatures
such forms of Life as We Know It are
present at hydrothermal vents in the
earth's oceans these vents are places
where the sea floor meets magma from the
Earth's mantle superheating the
surrounding water and creating a harsh
inhospitable environment
yet even here life finds a way and at
these vents thriving communities of
bacteria crabs and tube worms can be
found there water temperatures can reach
up to 464 degrees Celsius but instead of
vaporizing the water remains liquid
thanks to the pressure of the rest of
the ocean bearing down on it
in fact some scientists even believe
that life on Earth actually started in
hydrothermal vents it's surprising to
think that the same extreme conditions
that could wipe out most life on Earth
might be responsible for the very
existence of life itself
these remarkable organisms come in many
different types and can survive in some
of the harshest environments on Earth
and possibly Beyond
heat resistant organisms known as
thermophiles are able to survive at
temperatures of up to 120 degrees
Celsius well above the boiling point of
water
such similar organisms might be able to
survive on hot exoplanets such as hycin
worlds where temperatures can exceed one
thousand degrees Celsius
acidophiles are organisms that can
survive in acidic environments with a pH
of 3 or lower
hypoliths live underneath rocks in
deserts where they are exposed to
extreme temperatures high levels of
ultraviolet radiation and dryness to
survive they rely on unique adaptations
such as using photosynthesis or breaking
down minerals in rocks for energy
radio resistant organisms such as
danococcus radio durans are able to
withstand high levels of radiation they
are known as the world's toughest
bacterium and can survive radiation
doses that would kill most other
organisms including humans
they may even be able to survive on
exoplanets that are bombarded by the
intense radiation from their host Stars
methanobacterium found in wetlands and
even in the guts of animals and humans
this tiny microbe has an incredible
metabolic pathway that sets it apart
from other living beings unlike most
organisms that rely on oxygen to produce
energy
methanobacterium has the ability to
create its energy through the process of
methanogenesis which involves converting
hydrogen gas to carbon dioxide into
methane bypassing the use of oxygen
k218b could potentially Harbor life
forms that are similar to
methanobacterium where organisms could
thrive in the extreme conditions found
on high Sean planets where temperatures
can exceed 1000 degrees Celsius
imagine a hybrid of methanobacterium and
a heat resistant thermophile which could
survive the extreme temperatures and
conditions of a high Sean Planet this
hybrid organism could be a potential
solution for energy production on such
planets where traditional sources of
energy would not be sustainable so if
one of these planets had microbes
swimming in the oceans underneath thick
hydrogen atmospheres would we be able to
detect them
astronomers are eagerly awaiting for the
opportunity to gather spectroscopic
observations of heisian planets
understanding of a planet within the
habitable zone has the right ingredients
for life means searching for Bio
signatures Like Oxygen methane nitrous
oxide and ozone all of which are found
on Earth
the planet was given a score of 0.73 ESI
that is according to estimates
scientists consider it 73 percent
Earth-like quite soon they'll have a
number of hycin-like planets to study
which are located relatively close to us
ranging from 35 to 150 light years away
and the James Webb Space Telescope
already has the capability to examine
their atmospheres a biosignature
detection would transform our
understanding of life in the universe
and our place in it upside down
it seems like a series of mind-boggling
discoveries lies ahead of us and these
could definitely represent a completely
new class of habitable planets that we
should be exploring in more detail
while extremophiles are fascinating
examples of life's ability to adapt and
thrive in even the most extreme
conditions some might wonder that there
could be exoplanets that Harbor much
more diverse and Abundant Life perhaps
even giving rise to massive creatures
like the dinosaurs that once roamed our
own planet
these worlds could offer conditions that
make earth look mild in comparison
close your eyes and imagine a planet
where the ground beneath your feet is so
heavy that you'd weigh two or three
times what you do on Earth
where the sky is dominated by a massive
close-in star and where the air is thick
making it hard to breathe
welcome to the world of super Earths a
new class of planets that are Earth-like
but more massive than our own a world
where the Giants rule
this is galise 667 CC
a super Earth about four times the mass
of Earth
super Earths are a fascinating new class
of planets that share many similarities
with Earth but their sheer size and
gravity make them unique they can have
rocky icy or a combination of both
surfaces with geological features that
can be more extreme and noticeable than
those found on Earth mountains
volcanoes and canyons on these planets
could be taller larger and more
spectacular than anything we've seen on
our own planet
one of the most intriguing things about
super Earths is that they are far more
common in the Galaxy than Earth-like
planets
in fact they are estimated to make up a
significant portion of the planets in
our galaxy with studies suggesting that
one-third of all stars in the Milky Way
could have super Earths in their
habitable zones
while many super Earths are not
considered habitable in the traditional
sense some of them may be super
habitable these planets have the
potential to be even more suitable for
life than Earth itself they could be
older larger warmer wetter with higher
levels of oxygen stronger magnetic
fields and a longer living star
picture yourself standing on the surface
of Gilles 667cc as you look up to the
sky you'll see a massive close-in star
dominating The Horizon which is the
parent star of the exoplanet and two
other stars Illuminating the sky that
make up the Triple Star system
galise 667 CC completes one orbit around
its star in just under 30 days it's
located just about 7 million kilometers
or less than 5 million miles Mercury is
57 million kilometers from the Sun by
comparison its star a red dwarf belongs
to the m-type star category which are
the coolest and most abundant stars in
the universe with lifetimes that can
last trillions of years
these stars have their habitable zone
very close to the surface for comparison
our sun is a g-type star these are
medium-sized stars with surface
temperatures between 5 000 and 6000
Kelvin they emit radiation mostly in the
yellow part of the spectrum and have
lifetimes of around 10 billion years
interestingly K Stars which have
properties intermediates of G and M
stars are considered to be the sweet
spot for habitability they are abundant
in the galaxy and pump up the chances of
finding life
on Earth it took 3.5 billion years for
complex life and 4 billion years for
advanced life such as humans to evolve
if life were to originate on a planet
orbiting a k star there would be more
time for evolution to take place
compared to Earth this is because super
Earths which are planets larger than
Earth but smaller than Neptune could
provide more land mass and habitat
making them more suitable for life to
thrive
additionally super habitable worlds may
have higher gravity and a thicker
atmosphere which could help spread
beneficial organisms potentially leading
to a more diverse ecosystem
planetary scientists suggest that the
sweet spot age for a super habitable
exoplanet is around five to eight
billion years which would provide enough
time for complex and advanced life forms
to develop
planets with more moisture and an
average surface temperature 8 degrees
Fahrenheit warmer than Earth may be more
habitable because warmer and wetter
climates tend to have more diverse life
in fact some super habitable planets may
even resemble Earth during the
Carboniferous period about 359 million
years ago when the climate was similar
to a tropical rainforest there might
even be phytoplankton covering large
areas of the ocean perhaps as large as
continents on earth
with the possibility of such diverse and
complex life forms on super habitable
exoplanets the next generation of
enormous ground-based telescopes
including the 39 meter extremely large
telescope and the 25.4 meter giant
Magellan telescope will have the highest
prospects of discovering indications of
life in the atmospheres of these planets
these telescopes currently under
construction are expected to gather data
by the end of the decade astronomers are
aware that life's essential components
are present in the universe but livable
does not imply inhabited and even the
most habitable planet may not be
inhabited
it's plausible that life on Earth was
truly an exceptional accident until
scientists discover proof of life
elsewhere in the universe
if scientists continue to hunt for signs
of Life on these extremely livable super
Earths over the following years and
don't find any people might be forced to
believe that the universe is a lonely
Place
astronomers have used Earth as a model
and planets in the habitable zone around
stars for decades to learn the
conditions necessary to sustain life and
that is understandable at first however
this search is far too limited and
scientists have expanded their search
for life beyond the traditional
habitable zone around Stars
close your eyes and imagine a planet
adrift in the abyss of interstellar
space a cosmic Wanderer unfettered by
the gravitational pull of a parent star
this is PSO
j318.522 a rogue Planet six times the
mass of Jupiter and a surface
temperature of around 800 degrees
Celsius
not much is known about how these
planets come to exist but scientists
theorize that they are either failed
stars or planets that have been ejected
from a planetary system after an
encounter with another world
rogue planets normally grow faintly from
the heat of their formation but once
they cool down they disappear into the
darkness making them extremely difficult
to detect and observe
how would life adapt to such an unusual
world
at first glance a rogue Planet may seem
like a desolate Wasteland a Barren and
inhospitable place for life yet Recent
research suggests that some rogue
planets May possess the necessary
conditions for life to thrive
these planets may have thick atmospheres
that trap enough heat to sustain liquid
water which is essential for life on
Earth
while it may seem unlikely that life
could adapt to such an unusual world
it's worth considering the possibility
that a rogue Planet especially one that
was once part of a solar system could be
home to thriving life forms
in fact rogue planets May provide a more
stable environment for life to flourish
compared to orbiting Stars these planets
are free from the turbulence and
radiation that can arise from
interactions with a parent star this
means that any life forms that evolve on
rogue planets may be less likely to face
Extinction due to external factors
similar to high Sean worlds life on
rogue planets can Thrive near the
hydrothermal vents on the ocean beds
from these vents a constant flow of
minerals spews forth from the Earth's
mantle a perfect source of energy and
nutrients for bacteria to thrive
which in turn attract larger and more
complex creatures like snails fish
octopus and tube worms up to two meters
long
it's possible that the same process
could have occurred on rogue planets
with volcanic activity or other events
providing the energy and raw materials
needed for life to take hold
as time passes on these rogue planets
complex ecosystems could emerge with
predators and prey coexisting in a
delicate balance perhaps intelligent
life could arise a different type of
intelligence that we could never even
comprehend adapting to the extreme
challenges of living on a planet without
a parent star
these intelligent beings might never
break through the ice that blankets
their world and might never even realize
that there is such a thing as outside
their small world would be their entire
universe it's amazing to think about a
rogue Planet drifting between the Stars
yet carrying life with it of course all
good things must come to an end
eventually even the most resilient deep
sea creatures would be unable to survive
as the planet's core cools and its
oceans freeze over
millions of generations might live and
die in these dark oceans ignorant of the
vast and Incredible Universe that exists
beyond their icy prison
with the possibility of billions of
rogue planets scattered throughout the
Galaxy the search for life beyond our
solar system has taken an exciting new
turn
close your eyes and imagine a system of
seven planets
all roughly the size of Earth orbiting a
small dim star
this is the Trappist one system
located just 39 light years away from
our own solar system it was discovered
in 2017 and has since been regarded as
one of the most remarkable discoveries
in astronomy
what makes it so intriguing is that
three of its seven planets are situated
within the star's habitable zone which
means that they are at just the right
distance to potentially support liquid
water and possibly even life
and each of these worlds is far older
than Earth giving potential life forms
here a 3 billion year Head Start
over such an extended period life on
these planets may have had ample time to
evolve and diversify
potentially giving rise to Advanced
civilizations beyond our imagination
this Ultra Cool dwarf star around which
these planets orbit is much dimmer and
cooler than our sun
which means that the planets receive
less energy from their star
as a result any life forms that exist
here may be fundamentally different from
those we know on Earth
as you walk along the alien terrain you
notice something odd
the Sun never moves that's because all
of the planets in this system are
tidally locked to their star
starting with trappist-1g the coldest of
the habitable Trappist planets analysis
has shown that it has a density of 76
percent that of Earth indicating a large
amount of water on the planet most of
this water is likely in the form of
colossal ice sheet covering the majority
of the planet however despite its icy
exterior the possibility of Life
existing in this planet's frigid depths
cannot be ruled out
trappist-1f the next planet in the
Trappist lineup here you find an eyeball
Planet situated closer to the parent
star than its icy neighbor
the ice sheets on this planet have been
pushed further back creating a larger
focused crater that can potentially hold
significant water bodies
this planet has a radius almost
identical to Earth but with only 68
percent of its mass it is expected to be
another water-rich world with up to 20
percent of the planet's composition
consisting of water
this world is an ocean planet with ice
sheets tens even hundreds of miles deep
creating the perfect environment for
large lakes and a single vast ocean to
occupy the focus
in fact this planet is essentially one
giant fishbowl with an ESI score of 0.70
it's apparent that this planet is more
suitable for aquatic life than
terrestrial
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trappist-1d with a lower density than
Earth is expected to Harbor large
amounts of water possibly mostly in
gaseous form creating a thick swampy
water vapor atmosphere similar to Venus
however the excessive heat of the
planet's Focus May create a more
temperate climate across the night side
potentially allowing for the existence
of lakes or even oceans of water in
absolute Darkness
this planet has an ESI score of 0.91 and
while simulations of its conditions are
split between an Earth-like and a more
venus-like world the possibility of Life
existing in some form cannot be
dismissed
trappist-1e is situated slightly on the
warm side of the habitability Zone just
like Earth this planet has a size and
density nearly identical to our home
planet unlike its neighbors the planet's
greater density suggests that it
contains less water creating the
possibility of a mixed surface between
terrestrial and Marine environments
the similarities between this planet and
Earth are astounding making it hard to
imagine that life could not exist in
some form in this environment
trappist-1e has an ESI score of
0.95 making it the most Earth-like
exoplanet discovered to date
it's possibly the closest we've ever
come to finding an earth 2.0
the universe might be teeming with life
on Amazing planets and it's not just
limited to the Stars we can see
twinkling in the night sky
in the words of the great astronomer
Carl Sagan the universe is a pretty big
place if it's just us seems like an
awful waste of space
indeed when we consider the sheer size
and complexity of the cosmos it seems
almost inconceivable that Earth could be
the only planet to Harbor intelligent
life
perhaps there are intelligent beings out
there pondering the same questions we do
curious about their place in the
universe even now its inhabitants may be
examining images of a yellow g-type main
sequence star
somewhere in the Milky Way galaxy they
see a tiny pale blue dot tucked into a
remarkably circular orbit
will they wonder if they found that
other Earth
perhaps with intelligent life able to
communicate across the voids of space or
will they Wonder after pouring over
their data and running planetary
formation models is it big enough or
special enough to support life
German philosopher leibniz once famously
claimed that Earth is the best of all
possible universes
it's a claim that has stood the test of
time for over 300 years but in recent
times Studies have shown that the Earth
is not the ideal place that could exist
the planet's climate has fluctuated over
time from boiling oceans to a
planet-wide deep freeze due to tectonic
activity
and variations in the brightness of the
Sun for most of the Earth's 4.5 billion
year history humans and other huge
animals were unable to survive
simulation suggest that Earth's
long-term habitability was not
predetermined but rather a result of
chance
literally it is a blessing that we are
alive
maybe biology is truly very complex
requires such stable conditions and so
much time that Earth may very well be an
anomaly a rare Oasis Of Life
in many ways life on Earth is like a
grand Symphony with each species playing
its own part in a magnificent and
intricate composition from the tiniest
microbe to the largest whale each has
its own unique Melody to add to the
chorus
and just like a symphony life on Earth
is a thing of beauty a Wonder to behold
and a testament to the incredible power
of evolution
let's take care of it cherish it and
protect it for generations to come
Earth may very well be the rarest place
in the universe
and we get the privilege of calling it
home
foreign
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