Going Wild

Explanation: Dynamic jets of gas and dust surround one of the most active planetary surfaces in the solar system in this wild-looking picture of a comet nucleus . The comet's designation is 81P/Wild 2 of course (sounds like “vilt 2”), and the picture is a composite of two images recorded by the Stardust spacecraft's navigation camera during its January 2nd flyby . The composited images consist of a short exposure recording startling surface details of Wild 2's nucleus and a longer exposure, taken 10 seconds later, revealing material streaming from the surface. The left edge of the nucleus appears extremely jagged due to a strong shadow. Pitted and eroded after billions of years of outgassing and meteorite impacts, the nucleus pictured is only about 5 kilometers in diameter, while the jets of dust and gas ultimately leave trails millions of kilometers long. Stardust is scheduled to return samples of Wild 2's cometary dust , picked up during the flyby, to Earth in January 2006.