Size: At 3,000 miles (4,800 km) in diameter, Callisto is roughly the same size as Mercury. It is the third largest moon in the solar system, after Ganymede and Titan. (Earth's moon is fifth largest, following Io.) Temperature: The mean surface temperature of Callisto is minus 218.47...
Callisto has a diameter of about 4,800 km (3,000 miles)—less than 100 km (60 miles) shy of the diameter of theplanetMercury—and it orbits Jupiter at a mean distance of about 1,883,000 km (1,170,000 miles). The bulkdensityof Callisto is 1.83 grams per cubic cm, a little more...
Jupiter's icy moon Callisto is shown here in approximate natural color. At the lower left is the impact structure, Asgard surrounded by concentric rings up to 1,700 kilometers (about 1,050 miles) in diameter. A second ringed structure with a diameter of about 500 kilometers (310 miles) ...
The largest craters are surrounded by a series of concentric rings which look like huge cracks but which have been smoothed out by eons of slow movement of the ice. The largest of these has been named Valhalla. Nearly 3000 km in diameter, Valhalla is a dramatic example of a multi-ring ba...