so good evening everybody today I’m
going to be talking about something
which is usually taken in interest by
almost everyone it is about the search
for life beyond Earth want to start off
I want to ask you a question did any one
of you here ever wonder why are people
so curious why do we have this great
desire to learn to know new things
around us every day while curiosity may
be the driving force behind mankind’s
never-ending quest for knowledge and
over the history of mankind we have been
making lots and lots of discoveries
understanding the world around us better
every day whether it be inventing the
alphabet or Christopher Columbus
discovering America curiosity revolves
around us our desire to learn as helped
us push our boundaries to look for
things that we don’t normally expect to
see to discover amazing things
surprising things and this has led to us
knowing so much more about our planet
and our space and the and our place in
the universe it is also led to us
thinking about life beyond Earth and
whether or not life could exist beyond
Earth or not so far we are able to
explore the laws of physics and
chemistry beyond Earth but biology is
something that we are limited to that’s
because there is no hard evidence of
life beyond Earth till date so it’s
quite hard to speculate what life might
look like on other worlds and whether
the basic understanding of what life of
the basic understanding of how life
forms on Earth is similar to that on
other worlds or not so let’s make a
comparison here it is said that there
are more stars than all the grains of
sand in Earth’s beaches beaches deserts
and oceans combined now if you just give
all those grains of sand or a certain
number it’s going to be huge well
approximately there are around seven
quintillion grains of sand which is 7
followed by 18 zeroes now that is a huge
number
imagine there being more stars than that
well that is basically that that just
blew many stars into many planets for
life not to exist life has to exist
somewhere out there in space so the
question is where should we look for
life well the most common thing that
researchers are looking for is the
presence of liquid water and a planet
surface
water is the source of life and
everywhere we have looked on earth
whether it be ice-covered lakes or dry
deserts if there is water there is life
and that is what we are looking for in
fact we are so dependent on water that
we wouldn’t be able to lift three days
without water so these are a set of
graphs by famous planetary scientist dr.
Sean Goldman and I’ve tweaked it in a
way to make it more interesting and it
will basically help us to understand
what type of planets are we looking for
out there so as you go up the size of
the planets increases and as you move
towards the right the distance from its
star increases so these are some of the
planets in our solar system so when we
are looking for planets we are usually
looking for those planets that are not
too far away not too close from the Sun
that so they’re just right distances so
that they can hold liquid water and well
if a planet is just too close to the Sun
when all the liquid water would
eventually evaporate and it would just
become too hot for life to exist so
that’s a boundary we have there now a
planet cannot be too far away from the
Sun also because all that liquid water
would eventually turn into hard ice
which would make it life which would
make life hard to exist again so that is
another boundary now all that liquid so
a planet cannot be too big again
that’s because if it is then all there
just be too many gases out there in the
atmosphere and with so many gases it
would just become too dense for a liquid
water to exist and that’s another
boundary and a planet cannot be too
small that’s because if it is then it
would eventually lose it as with
atmosphere just like our very moon and
it would be not possible for a good
water to stay again so that is another
wall well these four walls these poor
boundaries create a box inside which is
our happy zone or we can say the
habitable zone and these are unplanned
it’s inside this habitable zone or
basically those planets which can
support life or probably have liquid
water existence and as you can see that
Mars actually falls in this habitable
zone so let’s have a look at our
neighboring planet Mars so Mars is a
rocky planet about half the size of
Earth it has an atmosphere and falls in
the habitable zone well everything all
good right but the good thing well the
disadvantage is that it’s a solute its
atmosphere is about 95 percent carbon
dioxide and temperatures range from 20
degrees Celsius on summer
to negative 195 degrees Celsius on
winter so you can see the difference
quite a lot well average temperature on
earth is about 14 degrees Celsius and in
Bangkok it’s like 27 degrees Celsius so
the difference is quite a lot and with
such low temperatures it is possible
that life may not be able to exist and
maybe the Mars isn’t the best place to
look for life but out of all the planets
in our solar system Mars seems to be the
most possible one most promising one
which is why there’s so much research
and discovery into exploring moss so
this is a rover that was sent to Mars on
2003 and it landed on 2004 and ha and
explored Mars for quite a long time and
helped return a lot of data back to
earth about Martian surface and
chemicals NASA’s Spirit rover and this
is another Rover that was sent to Mars
NASA’s Curiosity rover which was sent to
Mars in 2011 had landed on 2012 and has
been operating till now and this was a
really successful mission because it
helped to discover that water did exist
on Mars millions of years ago and it
could have supported microbial life well
recently NASA defined water on Mars
which is a quite exciting discovery
knowing that water is the source of all
life and a planet holding it just
happens to be nearby
and although the quantity of water is
quite less and seasonal it’s surprising
that water does exist in such low
temperatures so here’s an artist’s
conception of what Mars looked look like
now that’s the image to the left and
what it could have looked like millions
of years ago so did anyone see the news
recently NASA Spitzer Space Telescope
revealed the first known personal system
of 7 earth sized planets orbiting around
a single star just the Trappist one and
this is like a record-breaking discovery
of more the most number of stars the
most number of planets discovered
orbiting around a single star and all of
these planets could have liquid water
but the chances are highest between
planet EF and G that’s because they are
in the most right distances from the Sun
so well imagine that you were actually
standing in one of those planets now
what you would actually see is a large
star in front of you now this star is
quite small but I’ll come back to that
and you would if you actually looked up
to the night sky you would see other
planets and these neighboring planets
would be so close to Earth that if you
were so close to that planet that if you
were actually um if the humans actually
live there then we would already be a
multiplanetary species with our current
technology and behind that poster which
says planet hop from trap is one which
is that’s that’s because the planets are
so close to each other and behind that
poster is an artist’s conception of what
it might look like from that planet and
what the star looks quite big but if we
take in to scale then the star is
actually not quite big well above you
see our planet our star son and below
that is trap this one to Jupiter so trap
is one is just a little bit bigger than
Jupiter well this is about planets and
some of the planets we have discovered
and we are looking at but what if we
want to explore those planets in much
greater precision and detail well at
least for Mars let me introduce you to
this man his name is Elon Musk the owner
of SpaceX Tesla and SolarCity and some
other small adventures like you are
linked Hyperloop etc so he really aims
to send humans to Mars and make humans a
multiplanetary species and by setting up
a self-sustaining civilization on Mars
now how cool is that
well he plans to do this by the year
2025 which is quite a lot before NASA’s
in which is at the early 2030s so you
can see the difference that but looking
at his previous achievements we can see
that he might actually achieve his goal
because in seven years he received lots
of contracts from NASA to deliver cargo
to the International Space Station and
that is quite interesting so the main
way he’s trying to do this is by reusing
his resources what he’s trying to do is
actually young reuse rockets that are
actually sent to space he proposed this
idea of reusing rockets and recently
implemented in it in one of his rockets
called Falcon 9 which recently delivered
cargo to the International Space Station
and made it back landed back
successfully now this has helped to
reduce the cost of space travel
significantly and boost our chances to
reaching Mars even higher well that’s
Elon Musk now what if we want to look
about look for life beyond our solar
system look for planets that are really
far away from Earth well to do that
special telescopes such as this Kepler
space telescopes are being built and
this was a really
and mission it has helped discovering
thousands of planets and it’s something
which has been a really successful
mission so the basic working of this
telescope is by it monitors distant
stars out there and it continuously
looks at those stars waiting for a
planet to pass this pass by and when a
planet actually passes by it is
something like that it blocks certain
amount of light received by that star
and the more the telescope actually
monitors that light the reduction in
light and looks and basically
understands whether how large the planet
is and what’s its distance from its star
so imagine that you were a be standing
on one road and one open wide road and
your friend is ten kilometres away and
you’re trying to look at his ring
understand the texture and etc and that
is quite tough it looks simple in theory
but it’s quite hard to understand how
the reduction in light temperatures well
so that helps us to discover earth-like
planets but if you want to look for
planets we want to discover earth-like
planets right so we need to know the gas
composition etc and this is the James
Webb telescope which is launching in
October 2018 and it will help to
discover it will basically look at
planet atmospheres and look at the gas
composition and compared to planet Earth
and discover signs of life if need be
so technologies like this and those that
may be developed in the future will
significantly help to boost our chances
of finding earth-like planets and
finding a life maybe or intelligent life
and I can say that we may discover
intelligent life or life in the next
couple of years maybe in the next maybe
in the next few hours or maybe in next
year next ten years next 50 years well I
can say we may do that but it’s only a
matter of time before we do that and a
question of when thank you [Applause]