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[Music throughout]

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The Trojan asteroids are small bodies
 in our Solar System.

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They share an orbit with Jupiter. 

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There's two swarms of them. 

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One located 60 degrees
 ahead of Jupiter in its orbit,

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and the other swarm is located
 60 degrees behind Jupiter in its orbit.

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And these Trojan asteroids are remnants
 from planetary formation.

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So sometimes we'll call them
 the fossils of Solar System formation.

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Their near neighbors might have gone
 into forming the giant planets.

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And so these objects then became captured
 in their locations today.

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And so in that way,
 we can look and see what went

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into forming the planets
 in our Solar System.

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The main goal of the Lucy mission
 is to explore the Trojan asteroids.

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We want to understand
 where these asteroids came from

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and why they're so diverse.

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And this is going to be our first ever
 exploration of these objects.

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From the Earth, we can see
 certain features on the Trojan asteroids.

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We can see where they're located.
 We can see their colors.

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And we can get spectra. 

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Spectra can tell you
 about the surface composition.

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A spectrum is when you take light
 and spread it out

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into all its different wavelengths. 

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And so you have the brightness
 of the light as a function of wavelength.

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So think of it like a rainbow.

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But you're going to divide up the colors
 even more finely

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than just ROYGBIV.

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From Earth, the Trojan asteroids
 are just a point of light, and you can't

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tell one part of the Trojan
 asteroid composition versus another part.

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And Lucy is going to be able
 to get that detail close up.

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We'll be able to do that
 by taking this spacecraft

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and these instruments
 to the Trojan asteroids.

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And we'll be able to see 

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how the surface composition varies
 across the Trojan asteroids.

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Additionally, we have really large

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solar arrays because we are solar
 powered spacecraft.

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The spacecraft gets
 its power from the Sun.

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At the Trojan asteroids 

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we're more than five times
 further from the Sun than Earth is.

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So there's much less light. 

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We need large solar arrays
 to power our spacecraft.

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And in fact, we will be
 the furthest operating

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spacecraft powered
 by solar arrays during our mission.