Here, the VLA receives those reflected signals and processes them to make a radar map of the planet or other object. Below you will see some of those radar maps. This is believed to be due to significant amounts of water ice residing in permanently-shaded areas within craters in the polar region. The other two large regions of high reflectivity are in areas that never have been imaged by spacecraft, so the cause of the high reflectivity remains a mystery. This is a radar image of Mars, made with the Goldstone-VLA radar system in 1988.
Red areas are areas of high radar reflectivity.
The south polar ice cap, at the bottom of the image, is the area of highest reflectivity. The other areas of high reflectivity are associated with the giant shield volcanoes of the Tharsis ridge.