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given the inconceivable amount of
galaxies stars and planets in the
universe we can almost safely say that
life on other planets does exist sure
until we can actually prove at that
point there's that slight chance that
there is nobody out there however when
or maybe if we ever do meet aliens what
will they be like obviously we can't
know but we can make educated guesses a
good way to start is to look at
ourselves what to humans do when we find
new land people and/or creatures we have
never encountered before well for
example if we look at when Christopher
Columbus first discovered North America
it didn't exactly end too well for the
Native Americans basically throughout
history humans have conquered and taken
over land and resources so if aliens
that finds earth or anything like humans
it's most likely going to end very badly
for us however another point to consider
is the fact that if aliens have the
technology for interstellar and maybe
even intergalactic travel they might not
be very interested in us and from their
perspective our very primitive world
neil degrasse tyson explained it using a
pretty great analogy you don't want to
buy a worm and wonder what it's thinking
or try to communicate with it no you
either walk right past it or step on the
worm in other words if aliens ever do
find earth or maybe they already have we
might simply be too primitive for them
to even consider communicating with us
you can also look at this from the other
perspective what if we humans in say a
few hundred years or so have become so
technologically advanced that we are now
the aliens visiting more primitive
world's and to be honest this isn't that
unlikely just look at how much
technologically advanced we become says
the Industrial Revolution it only took
about three generations for us to go
from barely having electricity to having
what allows you to watch this video
right now the Internet so what would we
do
what would an even more advanced human
civilization do if we found primitive
life on another planet and actually had
a means to visit well there is something
called the zoo hypothesis which argues
that intelligent alien life ignores
earth to allow for natural evolution and
cultural development basically they
observe and maybe study us from afar and
are deliberately hiding from us because
they do not want to disturb our
development as a species and it's likely
humans would do something similar if we
found ourselves in such a situation in
the future it's possible that life could
exist on the Venus most likely in the
form of bacteria or something very small
but life nonetheless what's interesting
though is that it wouldn't be found on
the surface which is 460 degrees Celsius
no but in the clouds high up in the
Venusian atmosphere where the conditions
are actually quite hospitable the age of
the universe and its vast number of
stars suggests that unless the earth is
very unusual life in the universe should
be common but there is something called
the Fermi paradox the Fermi paradox
argues that if there are such high
estimates of life in the universe where
is everybody the basic point of the
paradox is this our son is a very young
and fairly typical star there are
billions of stars there are billions of
years older in our galaxy alone surely
some of these stars have earth-like
planets assuming the earth is typical
some of these planets have developed
intelligent life
at least a few of these civilizations
should have developed the means for
interstellar travel but even if they
have a very slow method of interstellar
travel the galaxy could be completely
colonized in just a few tens of millions
of years that may sound like much but
given how some of these civilizations
could have existed for billions of years
that timescale is nothing so again where
is everybody
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even though it's unlikely there's still
a possibility that the earth is the only
or one of the very few planets in the
universe with intelligent life forms
it's called the rare earth hypothesis it
suggests that since the development of
life on Earth was the result of a long
list of geological Astrophysical events
so cosmically random yet so crucially
specific it's unlikely for it to have
happened anywhere else in the universe
thus there's a slight chance we really
are alone on November 6th 1991
astronomer James Scott II discovered a
very strange object now known as 1991
b:g the Ennio or near-earth object is
around 6 to 12 diameters and has a very
earth-like orbit which is very difficult
to explain to be from natural sources
and more or less eliminates the
possibility of a man-made object the
object also has very rapid changes in
brightness which is led many to believe
it could be of artificial origin maybe
we'll know for sure during his next
close approach to the earth in 2016 in
1984 a team of meteorite hunters found a
meteorite now known as Allen hills 84001
it was blasted off the surface of Mars
some 4.5 billion years ago and landed on
earth 13,000 years ago it's no party
because the meteorite may contain
fossils of bacteria like life-forms from
Mars which could mean is the first solid
evidence of the existence of alien life
however of the numerous examinations of
the meteorite scientists are skeptical
to whether or not the shapes in the rock
really are fossils of Martian bacteria
there are thousands of UFO reports every
year of course UFO stands for
unidentified flying object and does not
mean it has to be artificial in origin
and 90% of cases can be explained in one
way or another but the other unexplained
10% are indeed interesting such is the
case of an event which took place over
Los Angeles in 1942 now known as the
Battle of Los Angeles a giant UFO would
actually hover over the city and be
witnessed by hundreds of observers
there's even photo evidence of the event
once more is that because this was
during World War two right off the Pearl
Harbor had been attacked the military
quickly pointed spotlights at the object
thinking it might be another attack soon
after they began firing and even sent
out fighter planes to attack and destroy
the UFO but nothing the object was hit
the button didn't seem to take in the
damage at all it kept on hovering over
the city with the military relentlessly
trying to bring it down before vanishing
without a trace the US Air Force later
blamed the event on a weather balloon
make of that would you will die no
caucus radio Durance
is a microbe discovered in 2002 that can
among other things resist enormous
amount of radiation this type of
resistance is unheard of on earth as it
would take several billions of years to
develop leading many to theorize that
this microbe my thoughts have originated
from Earth there is something called the
Drake Equation it's a formula used to
supposedly calculate the number of
active alien civilizations in the Milky
Way galaxy it works a little something
like this
first the average rate of star formation
per year in our galaxy then the fraction
of stars with planets the average number
of planets that can potentially support
life the fraction that can go on to
support life the fraction that can go on
to support intelligent life
the
of civilizations that develop a
technology detectable from space and
length of time such civilizations
release detectable signs into space
which would then give you the number of
civilizations in our galaxy in which
communication might be possible but as
you can see most of these factors are
completely or partly unknown and thus by
changing only one factor just slightly
can yield completely different results
so most of what I've said in this video
and what you'll hear about aliens in
general should be taken with a grain of
salt as it really is just theories and
guesswork until we find some solid
evidence there is no way of knowing just
how common or rare life on other planets
really are
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you
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