It looks like you're using an Ad Blocker.
Please white-list or disable AboveTopSecret.com in your ad-blocking tool.
Some features of ATS will be disabled while you continue to use an ad-blocker.
Hellas’ center is located at about 70ºE and 40ºS. The bottom of Hellas is the only place on Mars with a high enough atmospheric pressure for liquid water to stay on the surface (Phillips 2000). The energy of the Hellas impact has been estimated at about 5.33 × 1026 joules (Spexarth 2004). This is a blast of 1.27 × 1011 megatons which is equivalent to 8.48 × 1012 atomic bombs the size of the one dropped on Hiroshima (U. S. Department of Energy 2000).