WASHINGTON, June 25 (Xinhua) -- New analysis of Mars' terrain using NASA spacecraft observations reveals what appears to be by far the largest impact crater ever found in the solar system, the U.S. space agency announced on Wednesday.
NASA's Mars Reconnaissance Orbiter and Mars Global Surveyor have provided detailed information about the elevations and gravity of the Red Planet's northern and southern hemispheres.
A new study suggests that a giant northern basin that covers about 40 percent of Mars' surface is the remains of a colossal impact early in the solar system's formation, which must have been at least 3.9 billion years ago.
