WEBVTT FILE

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[Music]

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Hi, I'm Jim Green, the
director of Planetary Science

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here at NASA.

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OSIRIS-REx is an opportunity
to go back in time and visit an

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asteroid called Bennu.

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Bennu is a very primitive
object, created at the birth of

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our solar system.

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OSIRIS-REx is going to go there,
orbit Bennu for more than a

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year, and bring back a sample.

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Since September, when we
launched OSIRIS-REx, it has made

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wonderful progress in the solar
system, but is getting close to

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a very important place.

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This is the Earth's
Lagrangian point L4.

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Now a Lagrangian point are
special regions in and around

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our orbit, for which the
gravitational interaction

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between the Earth and the
sun nearly cancels out.

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This allows an object to be
trapped

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and remain in that location.

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So what's trapped at L4?

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Well we don't really know.

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We only know what's trapped
at L4 around other planets.

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At Jupiter these are hundreds
and hundreds of objects

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that we call Trojans.

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And so, at Earth's L4, if we
find anything

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we'll be calling them Earth
Trojans.

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Now what are Trojans?

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Well, these are small
bodies caught in this orbit for

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billions of years.

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The Earth has swept up all kinds
of material to be created as we

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know it today, and what's
left are those things

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that are sitting at L4.

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That's what makes it really
exciting to be able to go there,

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and OSIRIS-REx is nearly there.

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Beginning February 9th,
OSIRIS-REx is going to turn on

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its scanning camera. It's going
to scan the areas,

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it's going to look for these
objects.

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To follow along with
OSIRIS-REx, please go to

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nasa.gov/osiris-rex, or go to
asteroidmission.org

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[satellite beeping]