good afternoon my name is ty Scott one oven what do I mean to her once I and I
oven what do I mean to her once I and I
oven what do I mean to her once I and I work here in Sioux Joe as an
work here in Sioux Joe as an
work here in Sioux Joe as an astrophysicist my work is to study the
astrophysicist my work is to study the
astrophysicist my work is to study the universe and in particular my research
universe and in particular my research
universe and in particular my research is about trying to understand how the
is about trying to understand how the
is about trying to understand how the stars that you see tonight how they
stars that you see tonight how they
stars that you see tonight how they formed whether they have planets and
formed whether they have planets and
formed whether they have planets and what happens to those planets over time
what happens to those planets over time
what happens to those planets over time are they habitable do they look like
are they habitable do they look like
are they habitable do they look like planet Earth so when I was a young boy I
planet Earth so when I was a young boy I
planet Earth so when I was a young boy I grew up in the Netherlands not very far
grew up in the Netherlands not very far
grew up in the Netherlands not very far from where this photo was taken and I
from where this photo was taken and I
from where this photo was taken and I regularly looked up in the sky and I
regularly looked up in the sky and I
regularly looked up in the sky and I wondered like all these stars and
wondered like all these stars and
wondered like all these stars and planets where did they come from and can
planets where did they come from and can
planets where did they come from and can i travel there when I grow up can I go
i travel there when I grow up can I go
i travel there when I grow up can I go there in a spaceship and also could
there in a spaceship and also could
there in a spaceship and also could there be life out there and with so many
there be life out there and with so many
there be life out there and with so many stars out there billions and billions of
stars out there billions and billions of
stars out there billions and billions of stars out there there should be a planet
stars out there there should be a planet
stars out there there should be a planet that looked like planet Earth right and
that looked like planet Earth right and
that looked like planet Earth right and could there be aliens could they travel
could there be aliens could they travel
could there be aliens could they travel to planet earth could they visit us I
to planet earth could they visit us I
to planet earth could they visit us I didn’t know at that time and now 30
didn’t know at that time and now 30
didn’t know at that time and now 30 years later I still don’t know here you
years later I still don’t know here you
years later I still don’t know here you see a picture of a galaxy a galaxies
see a picture of a galaxy a galaxies
see a picture of a galaxy a galaxies consisting of more than a hundred
consisting of more than a hundred
consisting of more than a hundred billion stars and we live in a galaxy
billion stars and we live in a galaxy
billion stars and we live in a galaxy that looks a bit similar like this one
that looks a bit similar like this one
that looks a bit similar like this one our galaxy is called Milky Way also with
our galaxy is called Milky Way also with
our galaxy is called Milky Way also with hundreds of billions of stars and many
hundreds of billions of stars and many
hundreds of billions of stars and many of those stars they have planets
of those stars they have planets
of those stars they have planets actually in our Milky Way galaxy there’s
actually in our Milky Way galaxy there’s
actually in our Milky Way galaxy there’s one little star and the outside of that
one little star and the outside of that
one little star and the outside of that galaxy and that star we call Sun our Sun
galaxy and that star we call Sun our Sun
galaxy and that star we call Sun our Sun is a star all the other stars are also
is a star all the other stars are also
is a star all the other stars are also sons so our son has eight planets so
sons so our son has eight planets so
sons so our son has eight planets so maybe the other stars they might also
maybe the other stars they might also
maybe the other stars they might also have planets right and our son has one
have planets right and our son has one
have planets right and our son has one planet which is habit
planet which is habit
planet which is habit one planet where humans can live where
one planet where humans can live where
one planet where humans can live where life can exist and so far planet Earth
life can exist and so far planet Earth
life can exist and so far planet Earth is the only space in the only place in
is the only space in the only place in
is the only space in the only place in the universe where as far as we know
the universe where as far as we know
the universe where as far as we know life exists actually with such an
life exists actually with such an
life exists actually with such an incredibly large universe the universe
incredibly large universe the universe
incredibly large universe the universe is used billions and trillions of stars
is used billions and trillions of stars
is used billions and trillions of stars and planets it should be many places
and planets it should be many places
and planets it should be many places that look a little bit like this right
that look a little bit like this right
that look a little bit like this right should be many planets that look like
should be many planets that look like
should be many planets that look like Earth with life on it but so far we’ve
Earth with life on it but so far we’ve
Earth with life on it but so far we’ve been looking around we haven’t found any
been looking around we haven’t found any
been looking around we haven’t found any evidence for life why is that well to
evidence for life why is that well to
evidence for life why is that well to understand that question we can split it
understand that question we can split it
understand that question we can split it up in two parts the first part is how
up in two parts the first part is how
up in two parts the first part is how common are actually planets like this
common are actually planets like this
common are actually planets like this and the second question is well if
and the second question is well if
and the second question is well if planets like this exists how common is
planets like this exists how common is
planets like this exists how common is is life on such planets are we a special
is life on such planets are we a special
is life on such planets are we a special place in the universe or are these kind
place in the universe or are these kind
place in the universe or are these kind of place is very common let’s take a
of place is very common let’s take a
of place is very common let’s take a look at these questions so the first one
look at these questions so the first one
look at these questions so the first one is well how common are these planets in
is well how common are these planets in
is well how common are these planets in the universe so here you see a picture
the universe so here you see a picture
the universe so here you see a picture of the constellation of Orion you can
of the constellation of Orion you can
of the constellation of Orion you can see it tonight if you go outside if it’s
see it tonight if you go outside if it’s
see it tonight if you go outside if it’s not cloudy you can recognize it and by
not cloudy you can recognize it and by
not cloudy you can recognize it and by the three stars in the middle very
the three stars in the middle very
the three stars in the middle very easily you can recognize it so when you
easily you can recognize it so when you
easily you can recognize it so when you look at Orion you will see a couple of
look at Orion you will see a couple of
look at Orion you will see a couple of stars and a big black background and
stars and a big black background and
stars and a big black background and looks like empty space but when you look
looks like empty space but when you look
looks like empty space but when you look with an infrared camera that detects
with an infrared camera that detects
with an infrared camera that detects heat radiation you will actually see
heat radiation you will actually see
heat radiation you will actually see much more you will see that there is
much more you will see that there is
much more you will see that there is actually a lot of stuff between these
actually a lot of stuff between these
actually a lot of stuff between these stars and as astronomers we call that
stars and as astronomers we call that
stars and as astronomers we call that gas and dust gas and dust in space and
gas and dust gas and dust in space and
gas and dust gas and dust in space and it is actually a lot of stuff there and
it is actually a lot of stuff there and
it is actually a lot of stuff there and that stuff has gravity these big gas
that stuff has gravity these big gas
that stuff has gravity these big gas clouds in space they attract each other
clouds in space they attract each other
clouds in space they attract each other they become smaller they merge they
they become smaller they merge they
they become smaller they merge they clump together and they form stars and
clump together and they form stars and
clump together and they form stars and you can actually see at the yellow spots
you can actually see at the yellow spots
you can actually see at the yellow spots there that’s where new stars are forming
there that’s where new stars are forming
there that’s where new stars are forming and that’s where new planets are forming
and that’s where new planets are forming
and that’s where new planets are forming so if you come back here take a picture
so if you come back here take a picture
so if you come back here take a picture 2 million years later you will see some
2 million years later you will see some
2 million years later you will see some planets maybe some of them look like
planets maybe some of them look like
planets maybe some of them look like earth so schematically this is what
earth so schematically this is what
earth so schematically this is what happens you start out with a very big
happens you start out with a very big
happens you start out with a very big gas cloud in space have a lot of gravity
gas cloud in space have a lot of gravity
gas cloud in space have a lot of gravity it becomes smaller takes takes maybe a
it becomes smaller takes takes maybe a
it becomes smaller takes takes maybe a million years or two million years or so
million years or two million years or so
million years or two million years or so and then it comes together in the center
and then it comes together in the center
and then it comes together in the center 99% of the material goes to the center
99% of the material goes to the center
99% of the material goes to the center and forms a star and the other one
and forms a star and the other one
and forms a star and the other one percent of the material forms a disk
percent of the material forms a disk
percent of the material forms a disk around that star and it keeps orbiting
around that star and it keeps orbiting
around that star and it keeps orbiting that material keeps orbiting that star
that material keeps orbiting that star
that material keeps orbiting that star for maybe 10 million years but in the
for maybe 10 million years but in the
for maybe 10 million years but in the meantime it is making planets such as
meantime it is making planets such as
meantime it is making planets such as planet Earth so this is how we think
planet Earth so this is how we think
planet Earth so this is how we think planet Earth form so you have a star a
planet Earth form so you have a star a
planet Earth form so you have a star a newly formed star with it gasps discs
newly formed star with it gasps discs
newly formed star with it gasps discs around it in that gas disk you have
around it in that gas disk you have
around it in that gas disk you have atoms molecules they stick together they
atoms molecules they stick together they
atoms molecules they stick together they form dust particles that also stick
form dust particles that also stick
form dust particles that also stick together and ultimately grow and grow
together and ultimately grow and grow
together and ultimately grow and grow and grow two stones big stones of a
and grow two stones big stones of a
and grow two stones big stones of a meter of a kilometer and some of them
meter of a kilometer and some of them
meter of a kilometer and some of them that are big enough start due to their
that are big enough start due to their
that are big enough start due to their gravity attracting even more of this
gravity attracting even more of this
gravity attracting even more of this material and this crowd they grow very
material and this crowd they grow very
material and this crowd they grow very fast so in our solar system we had eight
fast so in our solar system we had eight
fast so in our solar system we had eight of these very big ones that happen to
of these very big ones that happen to
of these very big ones that happen to accrete all the leftover material and
accrete all the leftover material and
accrete all the leftover material and form planets so you see those stones
form planets so you see those stones
form planets so you see those stones they’re actually not all of them are
they’re actually not all of them are
they’re actually not all of them are gone some of them are still flying
gone some of them are still flying
gone some of them are still flying around the solar system today and if one
around the solar system today and if one
around the solar system today and if one of them collides with the earth tonight
of them collides with the earth tonight
of them collides with the earth tonight you will see a falling star if it’s a
you will see a falling star if it’s a
you will see a falling star if it’s a small one if it’s a big one then we have
small one if it’s a big one then we have
small one if it’s a big one then we have a problem right so that’s what happened
a problem right so that’s what happened
a problem right so that’s what happened to the dinosaurs they were killed by an
to the dinosaurs they were killed by an
to the dinosaurs they were killed by an impact of one of these asteroids in the
impact of one of these asteroids in the
impact of one of these asteroids in the meantime the Sun starts shining and the
meantime the Sun starts shining and the
meantime the Sun starts shining and the Sun already due to its intense radiation
Sun already due to its intense radiation
Sun already due to its intense radiation it blows away the very light
it blows away the very light
it blows away the very light materials that hydrogen helium the
materials that hydrogen helium the
materials that hydrogen helium the materials that make up the atmosphere
materials that make up the atmosphere
materials that make up the atmosphere and the heavy ones like rock and metal
and the heavy ones like rock and metal
and the heavy ones like rock and metal they stay near this done they say stay
they stay near this done they say stay
they stay near this done they say stay near the Sun so what you get if you do
near the Sun so what you get if you do
near the Sun so what you get if you do that we do a computer simulation for
that we do a computer simulation for
that we do a computer simulation for example and include all of this you’ll
example and include all of this you’ll
example and include all of this you’ll get a star and you get a couple of small
get a star and you get a couple of small
get a star and you get a couple of small planets made of stone and rock like our
planets made of stone and rock like our
planets made of stone and rock like our planet Earth with a very tiny atmosphere
planet Earth with a very tiny atmosphere
planet Earth with a very tiny atmosphere but almost entirely made of rock and
but almost entirely made of rock and
but almost entirely made of rock and stone and four huge planets or three or
stone and four huge planets or three or
stone and four huge planets or three or five depends a bit this is what we
five depends a bit this is what we
five depends a bit this is what we expect from the theory of planet
expect from the theory of planet
expect from the theory of planet formation it works for our solar system
formation it works for our solar system
formation it works for our solar system but does it also work for other solar
but does it also work for other solar
but does it also work for other solar systems and that was a big question up
systems and that was a big question up
systems and that was a big question up to about 20 years ago 20 years ago
to about 20 years ago 20 years ago
to about 20 years ago 20 years ago telescopes became strong enough to
telescopes became strong enough to
telescopes became strong enough to detect planets orbiting the stars that
detect planets orbiting the stars that
detect planets orbiting the stars that you see at night of course it’s very
you see at night of course it’s very
you see at night of course it’s very difficult because they’re so far away at
difficult because they’re so far away at
difficult because they’re so far away at the moment we already know more than
the moment we already know more than
the moment we already know more than 3,500 planets outside our solar system
3,500 planets outside our solar system
3,500 planets outside our solar system and of course a more interesting
and of course a more interesting
and of course a more interesting question is which one of these planets
question is which one of these planets
question is which one of these planets is actually suitable for life life as we
is actually suitable for life life as we
is actually suitable for life life as we know it that needs liquid water to some
know it that needs liquid water to some
know it that needs liquid water to some degree and this is well quantified in
degree and this is well quantified in
degree and this is well quantified in this this plot and the horizontal axis
this this plot and the horizontal axis
this this plot and the horizontal axis you see the distance between a planet
you see the distance between a planet
you see the distance between a planet and a star and then the vertical axis
and a star and then the vertical axis
and a star and then the vertical axis you see well how hot is the star how big
you see well how hot is the star how big
you see well how hot is the star how big how luminous is a star so for stars like
how luminous is a star so for stars like
how luminous is a star so for stars like our Sun if we want a planet like Earth
our Sun if we want a planet like Earth
our Sun if we want a planet like Earth to be habitable it shouldn’t be too cold
to be habitable it shouldn’t be too cold
to be habitable it shouldn’t be too cold it shouldn’t be too far away it
it shouldn’t be too far away it
it shouldn’t be too far away it shouldn’t be too close to the star and
shouldn’t be too close to the star and
shouldn’t be too close to the star and it should be at the right spot in the
it should be at the right spot in the
it should be at the right spot in the Green Zone and we call this the
Green Zone and we call this the
Green Zone and we call this the habitable zone so if you are outside
habitable zone so if you are outside
habitable zone so if you are outside that habitable zone you can’t live on
that habitable zone you can’t live on
that habitable zone you can’t live on that planet if you’re in the habitable
that planet if you’re in the habitable
that planet if you’re in the habitable zone it’s theoretically possible but for
zone it’s theoretically possible but for
zone it’s theoretically possible but for those of you that look carefully
those of you that look carefully
those of you that look carefully actually our neighbor planets
actually our neighbor planets
actually our neighbor planets Venus and Mars are also well on the edge
Venus and Mars are also well on the edge
Venus and Mars are also well on the edge of this habitable zone in theory there
of this habitable zone in theory there
of this habitable zone in theory there may be life there but it turns out for
may be life there but it turns out for
may be life there but it turns out for some reason it went wrong venus is too
some reason it went wrong venus is too
some reason it went wrong venus is too hot Mars is too cold and actually our
hot Mars is too cold and actually our
hot Mars is too cold and actually our moon is exactly at the right spot the
moon is exactly at the right spot the
moon is exactly at the right spot the perfect place but our moon is also dead
perfect place but our moon is also dead
perfect place but our moon is also dead why is our moon did it doesn’t have any
why is our moon did it doesn’t have any
why is our moon did it doesn’t have any atmosphere so one requirement for life
atmosphere so one requirement for life
atmosphere so one requirement for life is temperature but another one is
is temperature but another one is
is temperature but another one is atmosphere and it’s actually a very
atmosphere and it’s actually a very
atmosphere and it’s actually a very important one the air which we breathe
important one the air which we breathe
important one the air which we breathe so an atmosphere and a planet determines
so an atmosphere and a planet determines
so an atmosphere and a planet determines what what happens on the surface of a
what what happens on the surface of a
what what happens on the surface of a planet so and our planet Earth the
planet so and our planet Earth the
planet so and our planet Earth the atmosphere transports heat through winds
atmosphere transports heat through winds
atmosphere transports heat through winds our atmosphere is responsible for the
our atmosphere is responsible for the
our atmosphere is responsible for the greenhouse effect the greenhouse effect
greenhouse effect the greenhouse effect
greenhouse effect the greenhouse effect you always hear many bad stories about
you always hear many bad stories about
you always hear many bad stories about it but actually it’s good because
it but actually it’s good because
it but actually it’s good because without that greenhouse effect it would
without that greenhouse effect it would
without that greenhouse effect it would be minus 40 degrees in this room the
be minus 40 degrees in this room the
be minus 40 degrees in this room the atmosphere also provides nutrients
atmosphere also provides nutrients
atmosphere also provides nutrients oxygen for me and carbon dioxide for the
oxygen for me and carbon dioxide for the
oxygen for me and carbon dioxide for the plants and finally we have an ozone
plants and finally we have an ozone
plants and finally we have an ozone layer that protects us from dangerous
layer that protects us from dangerous
layer that protects us from dangerous radiation from space so if life wants to
radiation from space so if life wants to
radiation from space so if life wants to develop it on a planet and developing
develop it on a planet and developing
develop it on a planet and developing over long periods of time into an
over long periods of time into an
over long periods of time into an advanced civilization you need a stable
advanced civilization you need a stable
advanced civilization you need a stable atmosphere or at least one that changes
atmosphere or at least one that changes
atmosphere or at least one that changes very slowly and sometimes it goes wrong
very slowly and sometimes it goes wrong
very slowly and sometimes it goes wrong so in our earth that went wrong a couple
so in our earth that went wrong a couple
so in our earth that went wrong a couple of times actually quite a couple of
of times actually quite a couple of
of times actually quite a couple of times we had asteroids impacting the
times we had asteroids impacting the
times we had asteroids impacting the earth comets colliding with the earth
earth comets colliding with the earth
earth comets colliding with the earth wiping off the dinosaurs of this planet
wiping off the dinosaurs of this planet
wiping off the dinosaurs of this planet we had super volcanoes we had stars
we had super volcanoes we had stars
we had super volcanoes we had stars exploding not so far away from the Sun
exploding not so far away from the Sun
exploding not so far away from the Sun sterilizing most of the earth so so far
sterilizing most of the earth so so far
sterilizing most of the earth so so far our earth has survived all these natural
our earth has survived all these natural
our earth has survived all these natural disasters life has survived these
disasters life has survived these
disasters life has survived these natural disasters although with big pain
natural disasters although with big pain
natural disasters although with big pain every now and then
every now and then
every now and then so to sustain life for long periods of
so to sustain life for long periods of
so to sustain life for long periods of time you need a good temperature and a
time you need a good temperature and a
time you need a good temperature and a good atmosphere even if you can avoid
good atmosphere even if you can avoid
good atmosphere even if you can avoid this on some planets in the universe you
this on some planets in the universe you
this on some planets in the universe you will have additional problems you will
will have additional problems you will
will have additional problems you will have an advanced technology and advanced
have an advanced technology and advanced
have an advanced technology and advanced civilization that messes up the planets
civilization that messes up the planets
civilization that messes up the planets for example if you have a star with a
for example if you have a star with a
for example if you have a star with a planet and on that planet they discover
planet and on that planet they discover
planet and on that planet they discover nuclear energy and start making war with
nuclear energy and start making war with
nuclear energy and start making war with each other that cannot end good
each other that cannot end good
each other that cannot end good fortunately we survived that so far and
fortunately we survived that so far and
fortunately we survived that so far and our planet right we didn’t have a
our planet right we didn’t have a
our planet right we didn’t have a nuclear war air pollution can be
nuclear war air pollution can be
nuclear war air pollution can be tremendous well it’s a bit of problem
tremendous well it’s a bit of problem
tremendous well it’s a bit of problem now right but not so big that it is a
now right but not so big that it is a
now right but not so big that it is a problem for life and finally the
problem for life and finally the
problem for life and finally the greenhouse effect can go crazy you may
greenhouse effect can go crazy you may
greenhouse effect can go crazy you may have seen that in the news this is an
have seen that in the news this is an
have seen that in the news this is an example Venus where it went wrong with
example Venus where it went wrong with
example Venus where it went wrong with the greenhouse effect it’s incredibly
the greenhouse effect it’s incredibly
the greenhouse effect it’s incredibly hot now it used to have oceans but not
hot now it used to have oceans but not
hot now it used to have oceans but not anymore it became too hot too much co2
anymore it became too hot too much co2
anymore it became too hot too much co2 in the atmosphere that was not done by
in the atmosphere that was not done by
in the atmosphere that was not done by humans by the way this was just because
humans by the way this was just because
humans by the way this was just because the volcanoes happen to be a bit
the volcanoes happen to be a bit
the volcanoes happen to be a bit overactive so what about planet Earth
overactive so what about planet Earth
overactive so what about planet Earth what are we doing now to our atmosphere
what are we doing now to our atmosphere
what are we doing now to our atmosphere so you see here a picture of co2 levels
so you see here a picture of co2 levels
so you see here a picture of co2 levels over time measured by astronomers on a
over time measured by astronomers on a
over time measured by astronomers on a mountain in Hawaii the red curve shows
mountain in Hawaii the red curve shows
mountain in Hawaii the red curve shows the amount of co2 in the atmosphere
the amount of co2 in the atmosphere
the amount of co2 in the atmosphere since I was born which is well I’m not
since I was born which is well I’m not
since I was born which is well I’m not too young but about a bit less than 40
too young but about a bit less than 40
too young but about a bit less than 40 years is it’s a very short time on
years is it’s a very short time on
years is it’s a very short time on astronomical geological timescales since
astronomical geological timescales since
astronomical geological timescales since I was born co2 levels went up by twenty
I was born co2 levels went up by twenty
I was born co2 levels went up by twenty percent an incredible amount so whether
percent an incredible amount so whether
percent an incredible amount so whether this trend come from where did it start
this trend come from where did it start
this trend come from where did it start fortunately by studying the bubbles in
fortunately by studying the bubbles in
fortunately by studying the bubbles in the ice and Antarctica and Greenland we
the ice and Antarctica and Greenland we
the ice and Antarctica and Greenland we can find out what the atmosphere looked
can find out what the atmosphere looked
can find out what the atmosphere looked like in the past and dig a hole analyze
like in the past and dig a hole analyze
like in the past and dig a hole analyze the ice bubbles
the ice bubbles
the ice bubbles and this is what you can find for the
and this is what you can find for the
and this is what you can find for the last 2,000 years was rather constant for
last 2,000 years was rather constant for
last 2,000 years was rather constant for 2,000 years until about 1850 1900 what
2,000 years until about 1850 1900 what
2,000 years until about 1850 1900 what happened then what happened at that time
happened then what happened at that time
happened then what happened at that time it was the start of the Industrial
it was the start of the Industrial
it was the start of the Industrial Revolution that was James Watt and his
Revolution that was James Watt and his
Revolution that was James Watt and his steam engine that’s when we started
steam engine that’s when we started
steam engine that’s when we started using coal and oil on a massive scale
using coal and oil on a massive scale
using coal and oil on a massive scale and you see co2 levels have gone up by
and you see co2 levels have gone up by
and you see co2 levels have gone up by forty percent this is not the stock
forty percent this is not the stock
forty percent this is not the stock market of China this is not the American
market of China this is not the American
market of China this is not the American dollar this is the atmosphere of an
dollar this is the atmosphere of an
dollar this is the atmosphere of an entire planet sounds very dangerous to
entire planet sounds very dangerous to
entire planet sounds very dangerous to me if you go back even further and you
me if you go back even further and you
me if you go back even further and you can do that this picture shows a million
can do that this picture shows a million
can do that this picture shows a million years of history measurements of co2
years of history measurements of co2
years of history measurements of co2 levels and temperatures then coupled to
levels and temperatures then coupled to
levels and temperatures then coupled to it you see some variations we have ice
it you see some variations we have ice
it you see some variations we have ice ages every now and then these ice ages
ages every now and then these ice ages
ages every now and then these ice ages are natural and actually there is they
are natural and actually there is they
are natural and actually there is they are a result of astronomy they are a
are a result of astronomy they are a
are a result of astronomy they are a result of the orbit of the earth around
result of the orbit of the earth around
result of the orbit of the earth around the Sun changing sometimes it’s a bit
the Sun changing sometimes it’s a bit
the Sun changing sometimes it’s a bit more circular sometimes a bit more
more circular sometimes a bit more
more circular sometimes a bit more elliptical sometimes a bit closer
elliptical sometimes a bit closer
elliptical sometimes a bit closer sometimes a bit further that’s part of
sometimes a bit further that’s part of
sometimes a bit further that’s part of my research of astronomers like me we
my research of astronomers like me we
my research of astronomers like me we try to figure out what the planets are
try to figure out what the planets are
try to figure out what the planets are doing and we can predict this and
doing and we can predict this and
doing and we can predict this and geologists they measure this and thurs
geologists they measure this and thurs
geologists they measure this and thurs out pretty well except for the last
out pretty well except for the last
out pretty well except for the last point you see 1 million years of history
point you see 1 million years of history
point you see 1 million years of history of co2 levels and interest 100 years
of co2 levels and interest 100 years
of co2 levels and interest 100 years which is absolutely nothing in
which is absolutely nothing in
which is absolutely nothing in geological astronomical time skills we
geological astronomical time skills we
geological astronomical time skills we are changing the earth we are changing
are changing the earth we are changing
are changing the earth we are changing the earth sounds quite dangerous so now
the earth sounds quite dangerous so now
the earth sounds quite dangerous so now to go back to my original question the
to go back to my original question the
to go back to my original question the question that I asked when I was still a
question that I asked when I was still a
question that I asked when I was still a young boy so why are there so many stars
young boy so why are there so many stars
young boy so why are there so many stars and why haven’t I Lien’s come to visit
and why haven’t I Lien’s come to visit
and why haven’t I Lien’s come to visit us yet that may relate to this at least
us yet that may relate to this at least
us yet that may relate to this at least in my opinion
in my opinion
in my opinion so so far we have extremely good
so so far we have extremely good
so so far we have extremely good telescopes we went into space we’ve been
telescopes we went into space we’ve been
telescopes we went into space we’ve been to Mars we sent out messages radio
to Mars we sent out messages radio
to Mars we sent out messages radio signals light signals into space we’ve
signals light signals into space we’ve
signals light signals into space we’ve been listening space seems empty at
been listening space seems empty at
been listening space seems empty at least nobody is there to say hello to us
least nobody is there to say hello to us
least nobody is there to say hello to us why is that and the famous physicists
why is that and the famous physicists
why is that and the famous physicists and Rico Fermi he actually brought that
and Rico Fermi he actually brought that
and Rico Fermi he actually brought that up one time in the academic community
up one time in the academic community
up one time in the academic community during a coffee time at the University
during a coffee time at the University
during a coffee time at the University so he reasoned as follows and I’ve shown
so he reasoned as follows and I’ve shown
so he reasoned as follows and I’ve shown you in the first part first of all the
you in the first part first of all the
you in the first part first of all the universe has an incredible number of
universe has an incredible number of
universe has an incredible number of stars incredible number of planets and
stars incredible number of planets and
stars incredible number of planets and therefore also even if the chance may be
therefore also even if the chance may be
therefore also even if the chance may be very small an enormous number of planets
very small an enormous number of planets
very small an enormous number of planets that look like Earth planets that can
that look like Earth planets that can
that look like Earth planets that can potentially host life and some of these
potentially host life and some of these
potentially host life and some of these planets will be forming today some of us
planets will be forming today some of us
planets will be forming today some of us some of them formed maybe a million
some of them formed maybe a million
some of them formed maybe a million years ago or a billion years ago so
years ago or a billion years ago so
years ago or a billion years ago so civilizations there should be a billion
civilizations there should be a billion
civilizations there should be a billion years ahead in technology can you
years ahead in technology can you
years ahead in technology can you imagine what it looked like there’s some
imagine what it looked like there’s some
imagine what it looked like there’s some civilization there that is a hundred
civilization there that is a hundred
civilization there that is a hundred years ahead in technology or a thousand
years ahead in technology or a thousand
years ahead in technology or a thousand years or a million years incredible they
years or a million years incredible they
years or a million years incredible they should be able to send messages to us
should be able to send messages to us
should be able to send messages to us come say hello but they don’t it seems
come say hello but they don’t it seems
come say hello but they don’t it seems quiet where are they and that is called
quiet where are they and that is called
quiet where are they and that is called the Fermi paradox and of course many
the Fermi paradox and of course many
the Fermi paradox and of course many people have thought about what the
people have thought about what the
people have thought about what the solutions of this could be why the
solutions of this could be why the
solutions of this could be why the universe so big full should be full of
universe so big full should be full of
universe so big full should be full of earth-like planets and still we don’t
earth-like planets and still we don’t
earth-like planets and still we don’t see anybody maybe we’re the only ones in
see anybody maybe we’re the only ones in
see anybody maybe we’re the only ones in the universe right or maybe we are just
the universe right or maybe we are just
the universe right or maybe we are just the first one or maybe we should be
the first one or maybe we should be
the first one or maybe we should be lucky nobody has found us yet or maybe
lucky nobody has found us yet or maybe
lucky nobody has found us yet or maybe they’re hiding right maybe they don’t
they’re hiding right maybe they don’t
they’re hiding right maybe they don’t care about us actually what I think is
care about us actually what I think is
care about us actually what I think is the picture on the right so every now
the picture on the right so every now
the picture on the right so every now and then a civilization is wiped out by
and then a civilization is wiped out by
and then a civilization is wiped out by an asteroid impact or an exploding star
an asteroid impact or an exploding star
an asteroid impact or an exploding star that chance is relatively small what I
that chance is relatively small what I
that chance is relatively small what I think is that
think is that
think is that civilizations what they do they build up
civilizations what they do they build up
civilizations what they do they build up their technology and at some point they
their technology and at some point they
their technology and at some point they make an end to their own lives they mess
make an end to their own lives they mess
make an end to their own lives they mess up their planet so much either through a
up their planet so much either through a
up their planet so much either through a nuclear war or through changing the
nuclear war or through changing the
nuclear war or through changing the climate do you think an intelligent
climate do you think an intelligent
climate do you think an intelligent civilization would be so stupid to mess
civilization would be so stupid to mess
civilization would be so stupid to mess up their own planets I don’t know the
up their own planets I don’t know the
up their own planets I don’t know the answer we don’t know much about what
answer we don’t know much about what
answer we don’t know much about what happens in space the only thing I know
happens in space the only thing I know
happens in space the only thing I know is what happens on planet Earth that’s
is what happens on planet Earth that’s
is what happens on planet Earth that’s the only one I know and what we’re doing
the only one I know and what we’re doing
the only one I know and what we’re doing right now with planet Earth we we are
right now with planet Earth we we are
right now with planet Earth we we are changing planet Earth we are changing
changing planet Earth we are changing
changing planet Earth we are changing the atmosphere right now at a tremendous
the atmosphere right now at a tremendous
the atmosphere right now at a tremendous rate so when I was a young boy and I
rate so when I was a young boy and I
rate so when I was a young boy and I looked up to the stars and I wondered
looked up to the stars and I wondered
looked up to the stars and I wondered where are these aliens why are we alone
where are these aliens why are we alone
where are these aliens why are we alone then I look at Planet Earth what we are
then I look at Planet Earth what we are
then I look at Planet Earth what we are doing right now and I think this may be
doing right now and I think this may be
doing right now and I think this may be a reason and it’s good to realize that
a reason and it’s good to realize that
a reason and it’s good to realize that we’re changing the atmosphere it’s a
we’re changing the atmosphere it’s a
we’re changing the atmosphere it’s a human it’s not natural humans do it and
human it’s not natural humans do it and
human it’s not natural humans do it and therefore we may also be able to do
therefore we may also be able to do
therefore we may also be able to do something about it so this talk was
something about it so this talk was
something about it so this talk was about the universe actually it’s also
about the universe actually it’s also
about the universe actually it’s also about you this is your future this
about you this is your future this
about you this is your future this planet let’s take good care of it thank
planet let’s take good care of it thank
planet let’s take good care of it thank you
you
you [Applause]
”
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