Mercury (IMAGE) North Carolina State University Caption Enhanced color image of Mercury. The bright, circular deposit in the upper center of the image is an enormous effusive volcanic deposit, situated within the largest impact crater on the planet, the Caloris basin. Credit NASA/Johns Hopkins Applied Physics Lab/Carnegie Institution of Washington Usage Restrictions With credit License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.