The discrepancy between the original cost and the actual cost came in part because contractors originally were "overly ambitious" when estimating the project, Fischer said.

CNN: FBI turns on new crime-fighting system

Dr Amy Mainzer, principal investigator on the Neowise (Near-Earth Wise observations) project at the Jet Propulsion Lab (JPL) in California, said that "estimating the ages and origins of the asteroids should help us to correlate events on Earth and impact craters on the Moon with what is going on in the Solar System".

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