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A spacecraft called Lucy is set to launch tomorrow from Cape Canaveral on a 12-year journey. It will travel billions of miles into our solar system. It's on the hunt for cosmic fossils that might hold the key to how our solar system was formed. From member station WMFE in Orlando, Brendan Byrne explains.
BRENDAN BYRNE, BYLINE: The birth of our solar system was messy. Some 4.5 billion years ago, a dense cloud of gas and dust collapsed, spewing material all around. Most of that material became what is now our sun. The leftover stuff became our planets. But a tiny bit of that cosmic stuff is still out there in asteroids and meteors and comets. They're spread out in our solar system. But NASA's Hal Levinson (ph) said some have clustered into areas near Jupiter. They're called the Trojan asteroids.
HAL LEVISON: They're held there by the gravitational effect of Jupiter and the Sun. So if you put an object there early in the solar system history, it's been stable forever.
BYRNE: They've been stuck there like a collection of cosmic fossils. Levinson (ph) is leading the Lucy mission, sending a spacecraft to the Trojan asteroids. It's an ambitious undertaking. It's doing an intricate orbital dance and is going farther into the solar system than any other solar-powered spacecraft. The $981 million spacecraft came together in about 14 months, says NASA's Donya Douglas-Bradshaw. It's only about the size of a small car but has these massive circular solar arrays that make it look like a mouse.
DONYA DOUGLAS-BRADSHAW: You deploy those amazing solar arrays, cutting-edge solar array, and on end, the spacecraft spans about four stories.
BYRNE: Lucy's 12-year journey will take it to eight asteroids. Levinson (ph) says they're different colors, which could offer clues about where these asteroids came from.
LEVISON: So these things really are the fossils of what planets formed from, right? We understand planets formed as these things hit each other and grew and competed, and these are the leftovers of that.
BYRNE: Those leftovers will help us understand how our early solar system evolved, even our own planet. In fact, the spacecraft is named after the Lucy fossil. That's the 3-million-year-old skeleton of one of our early ancestors discovered in the 1970s. And NASA hopes the asteroids give us similar insight into our own origins.
For NPR news, I'm Brendan Byrne in Orlando.
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