... A Double Ringed Basin on Mercury . ... Credit Copyright: NASA / JHU APL / CIW Explanation: What created the internal second ring of this double ringed basin on Mercury? ... Double and multiple ringed basins, although rare, have also been imaged in years past on Mars, Venus , Earth , and Earth's Moon. ... One clue to the origin of the above-imaged double ring is that the basin center appears much smoother than the region between the rings. ... Publications with keywords: Mercury - Messenger . ...