Elysium-Amazonis-Olympus flows, Mars

Elysium-Amazonis-Olympus flows, Mars

Some lava flows are very rugged and strongly reflect radar signals, which can penetrate a meter or more of dust cover. This image, collected by the Arecibo radio telescope in Puerto Rico, shows rough lava flows (brighter tones) around several volcanoes and areas flooded by lava. The bright area at lower center is due to strong reflections from the part of Mars facing directly toward Earth during the observations.