Phobos, one of Mars' moons, transiting the Sun, as captured by NASA Mars Rover Curiosity. Phobos orbits Mars pretty close in, just about 6,000 km (3,600 miles) above the surface of Mars. Compare that to the 400,000 km distance from the Earth to the Moon! Phobos is so close that it transits the Sun pretty much every day for some location on Mars, making this something of a less-than-rare event. It'll only be a year before it happens again at Curiosity's location.
As the mountaineer reaches a high ridge, a ghostly figure towers out from the mist, its head sheathed in shimmering rings. This at one time unnerving apparition is the "Spectre of the Brocken", so named because of sightings on the Brocken, the highest peak of Germany's Harz Mountains.
One of the First Images This is one of the first images taken by NASA's Curiosity rover, which landed on Mars early Monday. It was taken with a fisheye wide-angle lens on the left "eye" of a stereo pair of Hazard-Avoidance cameras on the left-rear side of the rover.