NASA heading back to Mercury

NASA is set to launch a spacecraft to Mercury in August with a probe meant to orbit the heavy-metal planet while it maps its surface and looks for frozen water in shady polar craters.

Messenger won't make the first Mercury fly-by until 2008 and will not begin its main mission until 2011, after flying some 4.9 billion miles, the scientists said at a briefing. The roundabout route is geared to saving the cost and weight of the extra fuel required for a quicker trip.

The last time the National Aeronautics and Space Administration sent a spacecraft to this planet nearest to the sun was in 1974 and 1975, when the Mariner 10 probe made three close passes, returning detailed data on less than half of Mercury's surface.

MSNBC has this article.