Soft impacts left marks on protoplanet; process linked to life's origins on Earth
Scientists trace how dark asteroids smudged Vesta's facePrintSaveCreate your free profile or log in to save this articleNov. 1, 2012, 6:04 AM UTCBy msnbc.com technology & scienceSoft impacts left marks on protoplanet; process linked to life's origins on Earthmsnbc.com technology & science