Hellas Depression (image) University of Texas at Austin Share Print E-Mail Caption A depression located inside a crater on the edge of the Hellas basin region of Mars. New research suggests that the depression was formed by volcanic activity beneath an ice sheet -- an environment that could be suitable for microbial life. Credit Joseph Levy/NASA Usage Restrictions credit Share Print E-Mail 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.