Astronomy Picture of the Day

Explanation: Sometimes on Mars, there is nothing to see but red sand. Traveling two kilometres south of Endurance Crater, the robotic rover Opportunity now exploring Mars stopped and took a 360 degree panorama of a desolate and rusted Martian landscape. The site was dubbed Rub al Khali for its similarity to a barren part of the Saudi Arabian desert on Earth. In the centre of the frame, the tracks from the rover's grated wheels can be seen receding far into the distance. Near the bottom, several parts of Opportunity itself are recorded, including, on the far right, a Martian sundial. Nearly 100 images in three colours to generate the above spectacular real-colour image mosaic. To display the full high-resolution image would require about 300 computer monitors -- or one good large format printer.