By Nadia Drake
Asteroid 21 Lutetia isn’t just another pebble in a big pile of space rocks. Scientists now think it is a leftover planetary seed, booted into the main belt by the planetary bullies growing around it.
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Lutetia and its asteroid cousins are thought to be relics from the early solar system, rocky fossils that have recorded a history of the solar system’s early days in their pits and fractures. In July 2010, the European Space Agency’s Rosetta spacecraft flew within 3,200 kilometers of Lutetia, peered at the asteroid and attempted to read its stony story.