 If you think that a snowball’s chance on Mars is roughly the same as one in the mythical netherworld, park your eyes on this:
It’s ice in the pit of a Martian crater. The pictures were taken by NASA’s sharp-eyed Mars Reconnaissance Orbiter, which found highly pure, bright ice in five newly formed craters. Scientists had been comparing MRO images to look for changes, particularly dark marks associated with meteorite impacts. “We saw something very unusual -- this bright blue material poking up from the bottom of the crater. It looked a lot like water ice. And sure enough, when we started monitoring this material, it faded away like you'd expect water ice to fade,” said Shane Byrne, with the University of Arizona.
Water ice is unstable on the Martian surface, transforming quickly into atmospheric water vapor, he added. Scientists then used an MRO spectrometer to confirm the material was water. "All of this had to happen very quickly because 200 days after we first saw the ice, it was gone, it was the color of dirt," Byrne said. "If we had taken (the) images just a few months later, we wouldn't have noticed anything unusual. This discovery would have just passed us by." Byrne and 17 co-authors are reporting the findings in this week’s issue of Science. (NASA’s Mars Reconnaissance Orbiter took this image of a new, 8-meter (26-foot)-diameter meteorite impact crater in the topographically flat, dark plains within Vastitas Borealis, Mars, on November 1, 2008. The crater was made sometime after Jan. 26, 2008. Bright water ice was excavated by, and now surrounds, the crater. This entire image is 50 meters (164 feet) across. Credit: NASA/University of Arizona.)
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