Astronomy Picture of the Day

Explanation: The robot spacecraft NEAR Shoemaker continues to orbit asteroid Eros. This condensed 40-minute long time-lapse sequence taken last month shows what it looks like to pass within 200 kilometers of Eros' west end. The north pole of the rotating mountain is toward the bottom of the picture. This month NEAR-Shoemaker closes to within 100 kilometers, and by the end of this month will orbit only 50 kilometers from the center of this 33-kilometer long asteroid. One reason for moving in so close is to determine if 433 Eros has a magnetic field. NEAR Shoemaker, launched in 1996, is run by a computer similar to a PC released 15 years ago (12 MHz, 256K).