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This year, two missions will attempt
one of the most daring feats
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in space exploration.
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They will gather rock samples
from another world.
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The spacecraft have been launched
to two different asteroids,
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they'll gather samples, and they
will bring them back to Earth.
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So, why the sudden interest
in asteroids,
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and what can we learn from these
extraordinary missions?
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Welcome to The Sky At Night.
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When we think of the solar system,
we usually think of the planets,
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moons and the sun.
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But there's more to our
cosmic neighbourhood than that.
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Gathered in a vast doughnut-shaped
ring between Mars and Jupiter are
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millions of asteroids.
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Some are up to 300 miles across.
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Until now, we've only been able to
study asteroids - like this one -
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when they've fallen to earth.
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Or meteorites,
to give them their proper name.
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But now, missions have been launched
to bring pieces of two different
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asteroids back to Earth.
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These samples could unlock secrets
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about the origins of the
solar system...
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..and could even help save Earth
from a catastrophic collision.
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And so tonight, we're here at the
Natural History Museum in London,
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home to the world's largest
collection of meteorites.
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Coming up...
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We'll see the alarming number
of asteroids
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orbiting close to our planet.
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The impact energy if that thing
entered the atmosphere would be
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larger, 20 times larger than the
largest atomic device
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built during the Cold War.
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We'll talk to the scientists
attempting to bring pieces
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of an asteroid back to Earth.
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We have yet to have material brought
back to Earth from such a primitive
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body that will give us answers to
possible origins of life on Earth.
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And we'll meet the man who wants
to catch a shooting star.
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But first, we need to know
a little more about asteroids.
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Tim Gregory is here to explain
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why they can tell us so much about
our solar system.
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TIM: Here at the Natural History
Museum are thousands of samples
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of rocks from across the earth.
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Each one has a story to tell
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about the geological forces
that shaped our planet.
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But there is a limit to what these
rocks can tell us.
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The rocks on the earth are
always changing.
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They are being made and unmade and
remade by geological processes,
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so there's only so far back in time
that these rocks can take us.
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To look back to the very earliest
days of the Earth,
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or even further back to before
the Earth formed, you need
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something that's unchanged since the
beginning of the solar system.
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And that's where asteroids come in.
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The problem is getting our hands
on one.
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But, fortunately, we do have some
fragments here on earth.
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This one fell to the Earth on
Christmas Eve in 1965 in Barwell,
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a village in Leicestershire.
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It's a piece of an asteroid.
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And when a piece of an asteroid
falls through the Earth's atmosphere
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and lands on the ground,
we call it a meteorite.
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Pieces of this rock showered
the streets.
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Some fell through living room
windows and even damaged cars.
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Bet it was quite a shock for
the residents
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when this fell out the sky!
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Slice open a meteorite and they
start to reveal their secrets.
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Take a look at this one.
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These white, fluffy objects
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are called calcium aluminium
rich inclusions, or CAIs, and they
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are some of the oldest material that
you can get your hands on
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in our solar system today.
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The CAIs were the first solid
material to condense out of
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the solar nebula -
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the disc of gas and dust that gave
birth to our solar system.
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You cannot touch anything older
than this.
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And it's by dating CAIs just like
this one that we know the age of our
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solar system to be
4.6 billion years old.
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Surrounding them are these small,
pale beads.
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They're all round and that's because
they were once molten droplets of
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rock that cooled and crystallised
under zero gravity.
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They're called chondrules,
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and they're a major building block
of asteroids.
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And the black stuff holding it
all together?
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That's called the matrix,
and it was once free-floating dust
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that coalesced to help form
the asteroids.
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And amazingly, the matrix
contains water.
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For some rocks, like this one,
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that's as far as their
evolution went.
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It carried on orbiting the sun
for billions of years unchanged.
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But some asteroids grew bigger and
bigger and bigger, until eventually,
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they formed the planets.
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Exactly how you go from specks of
dust to something
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the size of a planet
is still not fully understood,
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but we do know that it was a
violent process.
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Written in some of these rocks
is evidence that asteroids were
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colliding and breaking up
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and melting and reforming early on
in the history of the solar system.
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This meteorite originated from an
asteroid that got so big it melted
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beyond all recognition.
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This one probably formed when a
rocky asteroid and a metal asteroid
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collided and mixed together.
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This shows how one rocky asteroid
has fragmented on impact
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with another metallic asteroid.
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Bits of rock have embedded
themselves
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within a molten, metal matrix.
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Contained within meteorites are most
of the ingredients and some of the
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instructions for how you build
a solar system,
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but there are still many
unanswered questions,
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and meteorites cannot help us
answer all of them.
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For one thing, they fall through the
atmosphere at 30,000 miles an hour,
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and develop this burned and charred
crust on their surface as they fall.
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And once they've landed, they
quickly become contaminated.
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To truly understand how our
solar system formed,
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what we'd like are some rocks from
an asteroid out there in space,
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pristine and unspoiled.
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And we may not have long to wait...
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There are currently two missions
attempting the seemingly impossible.
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To chase down an asteroid in space,
land on it,
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collect a sample and return
that sample to Earth.
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First in the race -
a Japanese mission called Hayabusa2.
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It recently arrived at asteroid
Ryugu, 190 million miles from Earth,
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and it sent back these images.
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The Hayabusa2 mission aims to bring
back a piece of Ryugu to help us
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learn more about the history
of our solar system.
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I spoke to Shogo Tachibana about the
plan now that the spacecraft
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has arrived at its destination.
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He's leading the team responsible
for collecting the samples.
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Hello, Shogo. Yes, can you hear me?
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I can hear you, we can't see you...
Oh, there you are.
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Hello! Nice to talk to you.
Yeah, good to see you.
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Thank you for talking to us today.
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What's the spacecraft doing now?
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OK, so Hayabusa2 recently arrived
at asteroid Ryugu on June 27.
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The spacecraft has been remaining
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at distance of about 20km
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to observe the asteroid,
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so we hope to very soon have a date
for our first sampling.
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And how will that sampling be done?
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We'll touch down on the surface
of the asteroid
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and as soon as this happens,
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a small projectile will be shot
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at the surface of the asteroid
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and ejected material will be
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collected in a capture.
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What are the challenges involved
with taking samples in this way?
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So, we will need to be
very cautious.
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The images of Ryugu have shown us
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it's a very rough and bumpy surface.
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A bumpy surface is a very dangerous
environment for the spacecraft,
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because the rocks may damage
the probe.
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So our engineering team is now
working hard to find a way
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to make a safe touchdown.
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Can you tell us how you're feeling,
and how the team are feeling?
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Are people excited, or are
you nervous?
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Excited and nervous.
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And especially...
So I am in charge of sampling,
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so we really need sample.
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Good. Well, look, we all wish you
the very best of luck.
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I hope it goes well.
Thank you so much.
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I hope we'll get to talk to you
about the science from the mission
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once you get your samples back.
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Thank you very much.
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Hayabusa2 is due to collect its
sample any day now.
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It promises to answer questions
about our solar system's origins.
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But there's another reason why
studying asteroids is so important.
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There's an awful lot of them
flying out there in space,
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but we know from Earth's history
that every now and then,
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one of them will collide with us.
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Were that to happen tomorrow,
the results could be cataclysmic.
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To find out how likely this is,
and what we can do about it,
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I met Alan Fitzsimmons.
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So, Alan, how do we check asteroids
that we don't know about?
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Well, we find asteroids the same way
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that the ancient Greek astronomers
found or identified the planets.
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Both planets and asteroids are
in orbit about our sun,
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and so that means
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over an hour or a few hours,
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you will see it moving against the
background stars and galaxies.
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And that's how we survey for
asteroids out there
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in our solar system.
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So, we can actually beam live to
Hawaii and find out what's happening
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with the telescope at the moment?
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That's right. What we're seeing here
are the data coming back from the
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ATLAS Project in Hawaii.
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That's two half-metre telescopes
surveying the night sky,
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looking for near-Earth asteroids.
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Although, tonight it's not looking
too good, unfortunately.
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Because we can see from the weather
map we've got a very large storm
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system, actually a hurricane,
south of the Hawaiian Islands.
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But we can have a look at what the
telescopes found last night.
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Oh, yes. And what we found
during the night,
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it found a lot of objects
moving across the sky.
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So, if we zoom in here we can
actually see
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in this part of the sky,
over an hour this object has moved
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from here down to here
in the night sky.
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And this is a real near-Earth
object.
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So, this is very important data
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because this will allow us to refine
the orbit and the trajectory of this
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asteroid, and it will give us a
little bit more insight into
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where it's going over the next
100, 200 years.
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So, you're detecting these asteroids
virtually every night,
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but do we have a feel of how many
of them are out there?
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I think we do now.
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This shows the inner solar system
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as we knew it 20 years ago
in the year 1998.
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And what we see here are the orbits
of the planets,
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the sun in the centre of the
solar system,
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and every one of these blue dots is
one of the few hundred near-Earth
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asteroids that were known then.
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OK. And over the past 20 years,
the technology we have,
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in terms of telescopes
and detectors,
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have really allowed us to detect
many, many more objects.
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I can illustrate the growth in our
knowledge of the near-Earth object
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population by playing
this animation.
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So here, we can see the asteroids
all rotating.
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Yeah, and you can see them moving.
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So you're tracking...
Whoa, OK!
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That's suddenly quite a
massive increase.
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And again... That side.
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What we're seeing here is the effect
of the increase in the power of our
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survey telescopes, which, every
clear night, are trying to look for
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these moving objects.
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That looks like thousands, and
it looks quite scary.
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Well, there are thousands.
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In fact, right now we've gone from
just a few hundred up to over 18,000
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near-Earth objects,
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and we find another 40 new ones
every month on average.
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So, looking at this, we know where
these asteroids come from,
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but how many near-Earth objects
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are actually dangerous to us,
on Planet Earth?
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Out of those 18,000, less than 2,000
are what we class as
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potentially hazardous objects,
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which come very close to the Earth's
orbit and are 140 metres across
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or so, or larger.
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So, what sort of impact with
something that size have?
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Oh, it would be pretty, pretty
disastrous for that local region.
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And, of course, the larger
the asteroid,
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the more impact it would have.
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Out of that 18,000, there's only
2,000 potentially hazardous?
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Yes. So that's 2,000
potentially ticking time bombs?
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And a case in point would be
the asteroid Bennu.
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This is a 500 metre,
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half a kilometre diameter,
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near-Earth asteroid that isn't
241
00:13:43,040 --> 00:13:45,070
going to approach us in the next 100
242
00:13:45,070 --> 00:13:47,020
years or so, but towards the end of
243
00:13:47,020 --> 00:13:48,070
the next century has about a
244
00:13:48,070 --> 00:13:52,030
one in 2,700 chance of hitting
the Earth.
245
00:13:52,030 --> 00:13:53,040
Sort of low probability,
246
00:13:53,040 --> 00:13:55,090
but the impact, I guess,
would be devastating? Absolutely.
247
00:13:55,090 --> 00:13:58,060
The impact energy if that thing
entered the atmosphere would
248
00:13:58,060 --> 00:14:00,040
be larger, 20 times larger,
249
00:14:00,040 --> 00:14:03,080
than the largest atomic device
built during the Cold War.
250
00:14:03,080 --> 00:14:07,050
And you'd really want to know,
for example, exactly how big it is.
251
00:14:07,050 --> 00:14:09,020
What is its mass?
What is its density?
252
00:14:09,020 --> 00:14:12,020
How is it constructed,
exactly what is it made of?
253
00:14:12,020 --> 00:14:15,020
Because all of that kind of
information would allow us to plan
254
00:14:15,020 --> 00:14:18,040
a deflection mission should
the need arise.
255
00:14:20,040 --> 00:14:22,080
Asteroid Bennu is a potential
threat.
256
00:14:25,000 --> 00:14:26,070
So, to discover all they can
about it,
257
00:14:26,070 --> 00:14:28,060
Nasa have sent the second of our
258
00:14:28,060 --> 00:14:31,040
two asteroid missions,
known as OSIRIS-REx,
259
00:14:31,040 --> 00:14:34,020
to intercept and to collect
a sample from it.
260
00:14:38,000 --> 00:14:41,030
Right now, it's making its
final approach to the asteroid.
261
00:14:43,080 --> 00:14:47,050
I spoke to Kerri Donaldson Hanna
from the OSIRIS-REx team.
262
00:14:50,040 --> 00:14:53,050
She's got the difficult task of
helping to select which bit of
263
00:14:53,050 --> 00:14:55,050
the asteroid to bring back to Earth.
264
00:14:58,040 --> 00:15:00,080
Where is the spacecraft now,
and what's it doing?
265
00:15:00,080 --> 00:15:03,060
OSIRIS-REx is on its way
to Bennu,
266
00:15:03,060 --> 00:15:07,010
so it started its approach phase
in mid August.
267
00:15:07,010 --> 00:15:10,040
And it's now about 2 million miles
away from Bennu,
268
00:15:10,040 --> 00:15:13,020
and roughly 60 million miles away
from Earth.
269
00:15:13,020 --> 00:15:15,060
And so what it means is we're
starting to get the first
270
00:15:15,060 --> 00:15:20,010
initial images of Bennu and start
resolving what Bennu looks like.
271
00:15:20,010 --> 00:15:23,080
It seems strange that you'd launch a
spacecraft somewhere without knowing
272
00:15:23,080 --> 00:15:25,040
what your target looks like.
273
00:15:25,040 --> 00:15:27,060
What do we know about
asteroid Bennu?
274
00:15:27,060 --> 00:15:31,030
We do kind of have a basic idea
of Bennu's shape.
275
00:15:31,030 --> 00:15:34,000
I mean, it just looks like a blob...
Yeah, yeah. ..to me.
276
00:15:34,000 --> 00:15:37,080
But you can see that while we have
the basic shape information,
277
00:15:37,080 --> 00:15:41,070
we still are missing a lot of
information about its surface,
278
00:15:41,070 --> 00:15:43,080
including whether it's big boulders,
279
00:15:43,080 --> 00:15:45,090
you know, where there's
lots of dust.
280
00:15:45,090 --> 00:15:48,020
And you need to pick somewhere
to land,
281
00:15:48,020 --> 00:15:51,050
which seems impossible with this
sort of information?
282
00:15:51,050 --> 00:15:55,040
In early December, we start doing
our preliminary survey,
283
00:15:55,040 --> 00:15:58,040
which means we start going into
orbit and we start mapping
284
00:15:58,040 --> 00:16:00,020
its surface properties.
285
00:16:00,020 --> 00:16:03,070
So all of this work is to identify
a single landing site
286
00:16:03,070 --> 00:16:06,080
which OSIRIS-REx will then go
to take samples from.
287
00:16:06,080 --> 00:16:09,070
How does that work? How do you get
a piece of an asteroid?
288
00:16:09,070 --> 00:16:11,060
So, the spacecraft is going to
289
00:16:11,060 --> 00:16:14,030
slowly make its way towards
the asteroid.
290
00:16:14,030 --> 00:16:16,040
The sample head will just touch
291
00:16:16,040 --> 00:16:20,030
the surface of the asteroid
for five seconds.
292
00:16:20,030 --> 00:16:22,020
That's it?
Yeah, just for five seconds.
293
00:16:22,020 --> 00:16:27,080
And in that five seconds, a burst of
nitrogen gas will be released,
294
00:16:27,080 --> 00:16:30,040
which will loosen all the
surface material.
295
00:16:31,040 --> 00:16:35,000
And it'll flush all the material
up into the sample head.
296
00:16:35,000 --> 00:16:37,070
And how much material do you get,
if you're lucky?
297
00:16:37,070 --> 00:16:41,080
We are hoping to get a minimum of
60g of sample.
298
00:16:41,080 --> 00:16:43,080
It's not very much.
But up to two kilograms...
299
00:16:43,080 --> 00:16:45,080
Oh, OK. ..of sample.
A couple of bags of sugar?
300
00:16:45,080 --> 00:16:46,080
Yeah, yeah. On Earth.
301
00:16:46,080 --> 00:16:49,050
What will your role and the role
of laboratories like this be?
302
00:16:49,050 --> 00:16:52,010
They want to make sure they can go
somewhere where they know
303
00:16:52,010 --> 00:16:55,080
they can actually touch down,
they will want to go somewhere safe,
304
00:16:55,080 --> 00:16:59,030
so that's, you know, worries about
the spacecraft itself.
305
00:16:59,030 --> 00:17:02,090
But then they also want to go
somewhere where they can actually
306
00:17:02,090 --> 00:17:05,000
sample as much material as possible.
307
00:17:05,000 --> 00:17:08,070
And they know that to get the
maximum amount of sample,
308
00:17:08,070 --> 00:17:11,080
they need a fairly flat surface,
309
00:17:11,080 --> 00:17:16,070
and they also need a fairly
boulder-free surface.
310
00:17:16,070 --> 00:17:20,060
So we're going to be making spectral
maps based on visible
311
00:17:20,060 --> 00:17:22,060
and near infrared reflected light,
312
00:17:22,060 --> 00:17:26,060
as well as thermal infrared
radiation emitted from the surface.
313
00:17:26,060 --> 00:17:30,060
So they'll pull all of these
different maps and try to pick
314
00:17:30,060 --> 00:17:33,000
the best science value place
on the surface.
315
00:17:34,050 --> 00:17:38,020
Hayabusa2 is due to return
its samples in 2020,
316
00:17:38,020 --> 00:17:41,050
followed by OSIRIS-REx in 2023.
317
00:17:41,050 --> 00:17:43,020
Now, that's a bit of a time to wait.
318
00:17:43,020 --> 00:17:44,030
So in the meanwhile,
319
00:17:44,030 --> 00:17:47,070
I want to find out what makes
these samples so special,
320
00:17:47,070 --> 00:17:49,040
and what we hope to learn
about them.
321
00:17:52,020 --> 00:17:54,070
I met with Ashley King, a geologist
322
00:17:54,070 --> 00:17:58,060
working with the rock collection at
the Natural History Museum.
323
00:17:59,090 --> 00:18:02,040
So, the samples you get will be
returned from an asteroid.
324
00:18:02,040 --> 00:18:03,070
What makes them so special?
325
00:18:03,070 --> 00:18:06,050
They'll be special because we're
getting them from an asteroid,
326
00:18:06,050 --> 00:18:08,000
but also we'll have context.
327
00:18:08,000 --> 00:18:09,090
So we'll know which asteroid they
come from and
328
00:18:09,090 --> 00:18:11,020
whereabouts on the asteroid.
329
00:18:11,020 --> 00:18:13,010
So, nearly all of the meteorites
that we have,
330
00:18:13,010 --> 00:18:16,000
we're pretty sure they come from
asteroids but we don't know exactly
331
00:18:16,000 --> 00:18:18,010
whereabouts, or which asteroids
they come from.
332
00:18:18,010 --> 00:18:22,010
So, I'm a geologist, so what I do
here on Earth is when you go out,
333
00:18:22,010 --> 00:18:23,090
you collect a sample,
you're actually...
334
00:18:23,090 --> 00:18:25,060
I have something here
I can show you.
335
00:18:25,060 --> 00:18:27,030
One you happen to have in your
back pocket.
336
00:18:27,030 --> 00:18:29,050
I have in my back pocket,
like all good geologists!
337
00:18:29,050 --> 00:18:32,010
This is a rock that was brought back
by Scott from Antarctica.
338
00:18:32,010 --> 00:18:34,030
Oh, wow. So this is...
Can I hold it? Absolutely, yeah.
339
00:18:34,030 --> 00:18:37,000
This is a piece of granite,
and so what we have here on Earth
340
00:18:37,000 --> 00:18:40,020
is that you can go to the outcrop,
you can see the rocks, you can,
341
00:18:40,020 --> 00:18:43,050
you know how that rock fits into the
bigger picture of that area.
342
00:18:43,050 --> 00:18:46,020
Then you can bring that sample back
and study it in the laboratory.
343
00:18:46,020 --> 00:18:48,060
Meteorites are brilliant because
we have the samples and we
344
00:18:48,060 --> 00:18:51,040
can study them in the lab. But we
don't have that original context.
345
00:18:51,040 --> 00:18:53,020
Where did they come from
on the asteroid?
346
00:18:53,020 --> 00:18:55,040
What were the other rocks...
What did they look like?
347
00:18:55,040 --> 00:18:56,080
How did they relate to each other?
348
00:18:56,080 --> 00:18:59,040
For these rocks that come back
from Hayabusa2 and OSIRIS-REx,
349
00:18:59,040 --> 00:19:00,060
we'll have that information
350
00:19:00,060 --> 00:19:02,070
which as a geologist,
is completely invaluable.
351
00:19:02,070 --> 00:19:05,040
What will be samples tell us
that we don't already know?
352
00:19:05,040 --> 00:19:07,080
One of the big questions in
planetary science is where
353
00:19:07,080 --> 00:19:09,020
did the Earth get its water from?
354
00:19:09,020 --> 00:19:12,000
We know from the meteorite record
that they look like meteorites
355
00:19:12,000 --> 00:19:13,030
that have water in them.
356
00:19:13,030 --> 00:19:14,040
This isn't liquid water,
357
00:19:14,040 --> 00:19:16,040
it's water that's locked up
within the minerals.
358
00:19:16,040 --> 00:19:19,000
When we go there, we'll be able to
get samples and study the water
359
00:19:19,000 --> 00:19:21,060
that's in these things and compare
it to what we see on the Earth.
360
00:19:21,060 --> 00:19:24,030
Yeah, we don't really know where
the Earth's water came from.
361
00:19:24,030 --> 00:19:26,010
We think maybe comets
was one option.
362
00:19:26,010 --> 00:19:28,060
It turns out from missions
like Rosetta, have kind of shown
363
00:19:28,060 --> 00:19:31,020
that the comets aren't the perfect
match for the water that we see
364
00:19:31,020 --> 00:19:33,040
here on the Earth,
so hopefully asteroids,
365
00:19:33,040 --> 00:19:36,000
or these asteroids, might give us
some clues to that.
366
00:19:36,000 --> 00:19:37,040
How about life? Yeah.
367
00:19:37,040 --> 00:19:40,010
The other interesting thing that
we're going to these asteroids,
368
00:19:40,010 --> 00:19:43,000
to Bennu and to Ryugu, because
they are dark.
369
00:19:43,000 --> 00:19:44,080
They are really black surfaces.
370
00:19:44,080 --> 00:19:47,050
One of the reasons we think these
things are so dark is that they
371
00:19:47,050 --> 00:19:48,080
probably got organic molecules
372
00:19:48,080 --> 00:19:51,080
and the kind of building blocks
for life are in there.
373
00:19:51,080 --> 00:19:53,060
These samples will be pristine,
374
00:19:53,060 --> 00:19:56,030
so they won't have been altered in
the terrestrial atmosphere.
375
00:19:56,030 --> 00:19:59,010
It'll be really exciting to see
whether asteroids like this are
376
00:19:59,010 --> 00:20:01,070
one of the ways that we can bring
the starting materials for life.
377
00:20:02,080 --> 00:20:04,090
But as well as life,
378
00:20:04,090 --> 00:20:09,000
asteroids threaten to deliver
death and destruction to our planet.
379
00:20:11,030 --> 00:20:14,040
Some of these near-Earth asteroids
are actually potentially hazardous.
380
00:20:14,040 --> 00:20:16,050
There's a possibility,
a very small possibility,
381
00:20:16,050 --> 00:20:19,050
that they could collide with the
Earth at some point in the future.
382
00:20:19,050 --> 00:20:22,020
So, one of the reasons we want to go
and study these things is to
383
00:20:22,020 --> 00:20:24,070
understand the composition,
the structure.
384
00:20:24,070 --> 00:20:27,000
Hopefully, if something was going
to hit the Earth,
385
00:20:27,000 --> 00:20:28,020
we can plan a bit about
386
00:20:28,020 --> 00:20:30,010
how we would deal with that
kind of problem.
387
00:20:30,010 --> 00:20:33,000
So, if we detect dangerous asteroid,
what can we do about it?
388
00:20:33,000 --> 00:20:35,040
I mean, Bruce Willis blew it up.
Is that a good idea?
389
00:20:35,040 --> 00:20:37,050
So, that's one thing
that's discussed.
390
00:20:37,050 --> 00:20:39,060
There's ideas, particularly
for these dark ones,
391
00:20:39,060 --> 00:20:42,010
there's this idea that we could go
and paint one side white
392
00:20:42,010 --> 00:20:45,060
and the solar radiation would just
nudge it off of its course
393
00:20:45,060 --> 00:20:47,000
ever so slightly.
394
00:20:47,000 --> 00:20:49,040
It's all about trying to change the
orbital path just enough
395
00:20:49,040 --> 00:20:50,070
so that it won't hit the Earth.
396
00:20:50,070 --> 00:20:52,030
I suppose, the more we know
about them,
397
00:20:52,030 --> 00:20:55,010
the more effective that will be.
Yes. Thank you.
398
00:20:58,050 --> 00:21:02,000
Whilst we wait for samples from
the two different missions,
399
00:21:02,000 --> 00:21:06,040
technology is giving us new ways to
understand more about asteroids
400
00:21:06,040 --> 00:21:07,080
from here on Earth.
401
00:21:09,060 --> 00:21:12,050
Pete Lawrence shows how you
can get involved.
402
00:21:17,060 --> 00:21:21,040
PETE: When small pieces of rock
pass-through Earth's atmosphere,
403
00:21:21,040 --> 00:21:25,010
they leave a bright light in the sky
called a meteor or a fireball.
404
00:21:27,030 --> 00:21:29,040
I've been fascinated by meteors
405
00:21:29,040 --> 00:21:32,060
and indeed fireballs for the past
40 years or so.
406
00:21:32,060 --> 00:21:36,040
And over that time, I've taken
tens of thousands of images.
407
00:21:36,040 --> 00:21:38,010
And I've been lucky enough
408
00:21:38,010 --> 00:21:41,000
to capture several hundred
meteor trails.
409
00:21:41,000 --> 00:21:43,040
But tonight, I'm going to try
something different.
410
00:21:43,040 --> 00:21:47,010
I'm going to try and capture
meteor trails using a video camera.
411
00:21:51,040 --> 00:21:56,060
Now, the camera I'm going to use is
a bog-standard security CCTV camera,
412
00:21:56,060 --> 00:22:00,090
and this is powered so that it
comes on as the sun sets,
413
00:22:00,090 --> 00:22:05,010
and the power's taken off via a
timer when the sun rises.
414
00:22:05,010 --> 00:22:07,080
Now, I'm going to set this up
permanently
415
00:22:07,080 --> 00:22:10,080
so it's looking for fireballs
all year round.
416
00:22:10,080 --> 00:22:14,000
And to do that, I need to use
a weatherproof housing,
417
00:22:14,000 --> 00:22:16,050
and this is a fairly bog-standard
bit of kit as well.
418
00:22:18,050 --> 00:22:22,010
The camera needs to point at a
clear patch of sky,
419
00:22:22,010 --> 00:22:25,070
so I'm mounting mine onto the
side of my garden shed.
420
00:22:27,010 --> 00:22:30,090
The camera is connected to an
ordinary computer with software
421
00:22:30,090 --> 00:22:34,020
that will identify and record
any fireballs that occur.
422
00:22:38,030 --> 00:22:41,020
Now, I've only had my camera set-up
for the past couple of nights,
423
00:22:41,020 --> 00:22:42,060
but rather excitingly,
424
00:22:42,060 --> 00:22:47,030
I have managed to capture a number
of meteor trails over that period.
425
00:22:47,030 --> 00:22:52,030
I've got a very nice one here that's
running down the sky beautifully
426
00:22:52,030 --> 00:22:54,020
against the stars of Pegasus.
427
00:22:56,040 --> 00:22:58,020
They are not particularly
bright meteors,
428
00:22:58,020 --> 00:23:00,010
but they have recorded really well
429
00:23:00,010 --> 00:23:02,030
with this actually quite simple
set-up.
430
00:23:03,070 --> 00:23:05,020
The great thing is that, with it,
431
00:23:05,020 --> 00:23:10,050
I can join the UK Meteor Observation
Network, or UKMON, as they're known.
432
00:23:10,050 --> 00:23:12,070
This is a group of amateur
astronomers
433
00:23:12,070 --> 00:23:16,000
that have set up cameras
all over the UK.
434
00:23:16,000 --> 00:23:19,010
And if you do so and you catch
a meteor trail passing through the
435
00:23:19,010 --> 00:23:20,040
field of view of your camera, the
436
00:23:20,040 --> 00:23:24,020
likelihood is that another camera
will have picked it up as well.
437
00:23:24,020 --> 00:23:27,080
If that happens, then you can
work out the height of the meteor,
438
00:23:27,080 --> 00:23:29,050
its speed, and also,
439
00:23:29,050 --> 00:23:33,000
you can track it back to work out
the particle's orbit that created
440
00:23:33,000 --> 00:23:35,020
the meteor in the first place.
441
00:23:35,020 --> 00:23:37,090
So, you're doing real
meteor science.
442
00:23:41,050 --> 00:23:44,090
Tracking where meteors come from
is important work.
443
00:23:44,090 --> 00:23:46,050
But there's a bigger prize.
444
00:23:47,050 --> 00:23:51,060
Most meteors are nothing more than
tiny sand-sized particles
445
00:23:51,060 --> 00:23:53,010
that burn up in the atmosphere.
446
00:23:55,000 --> 00:23:57,060
But some are big enough to make it
to the ground.
447
00:23:58,080 --> 00:24:02,060
Like this one that was filmed over
Perth fewer than two weeks ago.
448
00:24:07,060 --> 00:24:12,010
Luke Daly is helping to set up a
global network of cameras
449
00:24:12,010 --> 00:24:16,080
to not only track, but to recover
meteorites that have hit the Earth.
450
00:24:20,010 --> 00:24:24,030
One of his cameras is on the roof of
a stately home in North Yorkshire.
451
00:24:26,020 --> 00:24:29,070
We're setting up a network
of ten cameras here in the UK.
452
00:24:29,070 --> 00:24:31,060
Basically, like this one.
453
00:24:31,060 --> 00:24:33,050
It's got a nice fish-eye lens,
454
00:24:33,050 --> 00:24:36,040
so we see the entire night sky
all the time.
455
00:24:36,040 --> 00:24:39,040
It takes 30-second-long exposures.
456
00:24:39,040 --> 00:24:41,060
And so, if a fireball comes through
our images,
457
00:24:41,060 --> 00:24:45,000
we see it on this camera,
and hopefully we see it
458
00:24:45,000 --> 00:24:49,030
on another camera and we can
start sort of seeing what's
459
00:24:49,030 --> 00:24:52,080
flying around up in the atmosphere
at all times across in the UK.
460
00:24:55,040 --> 00:24:57,090
The camera's been down for
the last few nights,
461
00:24:57,090 --> 00:25:01,010
and so Luke has come to carry out
some vital maintenance.
462
00:25:02,020 --> 00:25:03,080
Getting to the camera's very easy,
463
00:25:03,080 --> 00:25:07,080
it's just these three Phillips head
screws - we just wind them off.
464
00:25:07,080 --> 00:25:10,050
Then this top just pops off like so.
465
00:25:11,090 --> 00:25:14,030
As I suspected, we've got this
card read error.
466
00:25:18,000 --> 00:25:20,060
Now we just need to see if it'll
take a picture for us.
467
00:25:21,080 --> 00:25:24,020
Once all of the cameras
are up and running,
468
00:25:24,020 --> 00:25:27,040
Luke and his team will be able to
see all of the meteorites
469
00:25:27,040 --> 00:25:29,040
that land anywhere within the UK.
470
00:25:31,030 --> 00:25:35,040
He hasn't found any yet,
but the concept has been proven.
471
00:25:35,040 --> 00:25:39,060
He helped set up a similar network
under the clear skies of Australia,
472
00:25:39,060 --> 00:25:41,000
which has seen success.
473
00:25:42,070 --> 00:25:45,060
So, when multiple cameras
see the same event,
474
00:25:45,060 --> 00:25:49,040
we are able to quite precisely
mapped that trajectory.
475
00:25:49,040 --> 00:25:52,040
In Australia, three of our stations
so the same event,
476
00:25:52,040 --> 00:25:54,030
and we were able to get that
trajectory,
477
00:25:54,030 --> 00:25:56,040
triangulate it down to the ground,
478
00:25:56,040 --> 00:25:58,030
figure out very precisely
where it landed.
479
00:26:00,010 --> 00:26:03,000
In 2016, these images of the
same fireball
480
00:26:03,000 --> 00:26:06,020
led one of Luke's colleagues
to a remote location
481
00:26:06,020 --> 00:26:08,000
in the Australian desert.
482
00:26:11,070 --> 00:26:14,080
Buried half a metre into thick mud
483
00:26:14,080 --> 00:26:16,050
was a two-kilo meteorite.
484
00:26:20,010 --> 00:26:23,000
It's an iron meteorite, mate.
Oh, my gosh!
485
00:26:23,000 --> 00:26:26,040
Phil, how does it feel to find
your first DFN meteorite?
486
00:26:26,040 --> 00:26:27,090
Splendid!
487
00:26:27,090 --> 00:26:29,090
LUKE LAUGHS
488
00:26:29,090 --> 00:26:33,000
So, as well as getting the full
position of these rocks,
489
00:26:33,000 --> 00:26:35,070
we can also track it back into
our solar system
490
00:26:35,070 --> 00:26:38,040
and get its orbit really precisely.
491
00:26:38,040 --> 00:26:42,010
And from that, we can start to
figure out where these rocks
492
00:26:42,010 --> 00:26:44,080
are coming from, and even what
asteroid or asteroid family
493
00:26:44,080 --> 00:26:46,020
they're originating from.
494
00:26:47,060 --> 00:26:51,080
Luke's team are working on a method
to calculate the precise journey
495
00:26:51,080 --> 00:26:55,000
that each rock has taken before
landing here on Earth.
496
00:26:56,070 --> 00:26:59,090
So, understanding where meteorites
come from as the sort of oldest
497
00:26:59,090 --> 00:27:03,060
material, and understanding how
that has evolved over time,
498
00:27:03,060 --> 00:27:07,050
and how our solar system
has evolved, gives us a...
499
00:27:07,050 --> 00:27:11,050
Sort of enhances our understanding
of how the planets form,
500
00:27:11,050 --> 00:27:14,080
how our planet formed,
what's special about our planet
501
00:27:14,080 --> 00:27:17,000
that it developed life
when others didn't.
502
00:27:19,080 --> 00:27:22,090
Much of what we know about the early
solar system comes from studying
503
00:27:22,090 --> 00:27:24,040
asteroids and meteorites.
504
00:27:24,040 --> 00:27:27,050
Yes, cos these are time capsules,
relics from the past,
505
00:27:27,050 --> 00:27:29,020
and they tell us about our origins.
506
00:27:29,020 --> 00:27:30,080
But there's still a lot to learn.
507
00:27:30,080 --> 00:27:33,070
That's where Hayabusa2 and
OSIRIS-REx come in.
508
00:27:33,070 --> 00:27:37,050
The samples they return will give us
an unprecedented window into the
509
00:27:37,050 --> 00:27:39,070
history of the early solar system.
510
00:27:39,070 --> 00:27:42,040
As to what they'll find,
we'll just have to wait and see.
511
00:27:42,040 --> 00:27:45,000
But we'll be here to tell you
all about it.
512
00:27:45,000 --> 00:27:46,020
Goodnight.
42507
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