Opportunity has seen many sights during her nearly 2000 sols on Mars, but recently came face-to-face (or wheel-to-rock) with the youngest crater ever seen by either Mars Exploration Rover!
Scientists say this small crater called "Resolution" formed sometime in the past 100,000 years. Most features studied by Opportunity are much older, including rocks over 3 billion years old! In contrast to these seniors, Resolution is just a baby.
Unlike a baby's soft skin, a newborn crater starts out sharp, and only softens over time. As craters age, the "sandblasting" action of the Martian wind erodes rocks ejected during crater formation and fills its bowl with sand. Signs of this crater's youth are fresh rocks on the crater rim and an empty bowl. The newer crater also drapes over older surrounding dunes. Finding youth pays off: scientists can compare Resolution to older craters to learn how fast wind changes the Martian surface over time.
Credit for image: Opportunity Rover, portion of Navcam mosaic (Sol 1825; PIA 1185).
Image credit: NASA/JPL-Caltech
Article courtesy of http://marsrovers.jpl.nasa.gov/spotlight/20090429.html
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