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NARRATOR: Asteroid Bennu
is a fascinating object.

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It records our solar system's
earliest history,

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contains information about the
origins of life,

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and has uncertainties in
its orbit

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that leaves a small possibility
of impacting Earth

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late in the twenty-second
century. 

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These properties make Bennu
the perfect target for NASA's

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OSIRIS-REx asteroid
sample return mission.

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LAURETTA: It's a great adventure
to explore an unknown world.

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We're going to reach out and
touch it, and then we're going

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to bring treasure back to
Earth for scientific analysis.

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To me it doesn't get any
more exciting than that.

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[logo music]

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NARRATOR: There is a huge
scientific payoff of delivering

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a sample of asteroid Bennu
directly into the hands of
scientists.

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LAURETTA: We want to understand
the origin of the Earth,

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the origin of the Moon, the
other terrestrial planets,

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but the earliest histories of
those bodies is wiped out.

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The asteroids record the
earliest stages of the solar
system.

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So it really is a time capsule
from the very dawn

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of the history of our solar
system.

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My dream is that we find
something that's unique, that's

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not represented in our meteorite
collections, and is really

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organic-rich material on the
surface of this asteroid

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that holds all kinds of
scientific treasures about the
origin of life

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and organic molecular
evolution in the solar system.

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NARRATOR: In addition to the
planetary science, sending a

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spacecraft to asteroid
Bennu will let us better

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understand the orbit of
this near-Earth object.

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Bennu is four to five thousand
times more massive than the
meteor

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that exploded above Chelyabinsk,
Russia in 2013,

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and there's a small chance that
Bennu could hit us late in the
next century,

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depending on how
its orbit evolves.

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LAURETTA: In order to accurately
predict its future orbital
evolution,

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we have to not only understand
the force of gravity,

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but thermal forces on the
asteroid can significantly alter
its future path.

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So we're going to study not only
the thermal emission coming off
of Bennu,

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but we're also going to build up
a global model to make sure

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we understand the theory
that underlies this, so that we

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can use it to accurately predict
where Bennu's going to be in the
future

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and apply it to other
potentially hazardous asteroids

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to really help us
understand the impact hazard.

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NARRATOR: OSIRIS-REx will launch
in September 2016 and arrive at
asteroid Bennu in 2018.

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Once the team is ready, they
will use the Touch-and-Go

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Sample Acquisition Mechanism,
TAG-SAM, to grab a sample off
the surface.

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LAURETTA: We have a unique
design where we put this TAG-SAM

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device onto the surface of the
asteroid, and then we blow down

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high-pressure nitrogen gas to
kind of agitate the soil

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and then basically scoop it
up in a giant air filter.

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That whole process takes five
seconds, so it's kind of get in,

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get the sample, and
get out of there.

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NARRATOR: There's good reason to
think this approach will work.

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One of the challenges of
sampling an asteroid

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is navigating in a
low-gravity environment.

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And with so little gravity,
objects have a tendency to
bounce.

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LAURETTA: Our design is to
bounce off the surface of the
asteroid.

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In fact we've got a spring
in the forearm of our TAG-SAM
device

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which is acting literally like a
pogo stick to push us off

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the surface of the asteroid
after we make that initial
contact.

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So from everything that I've
seen, trying to bounce off the

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surface of the asteroid is the
easiest way to get that
material.

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NARRATOR: Once OSIRIS-REx
delivers the asteroid sample

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to Earth in 2023, it will have
brought back the largest sample

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of an extraterrestrial body
since the Apollo missions,

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and like the moon rocks from
Apollo, the sample will be

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studied for decades to come
with ever increasing technology.

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LAURETTA: This is really a
treasure of information about

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the history of our solar
system, and will not only solve

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the scientific questions
that we're asking today, but
those that

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people will be asking for many
generations into the future.

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[swoosh] [beep beep,
beep beep, beep beep]