What caused the Hellas Planitia crater and the Tharsis bulge on Mars?
I agree with Donald Patten that both the Hellas Planitia and Tharsis were formed when an asteroid hit Mars. The center of the Hellas Planitia crater is around 41.5 degrees South and 72.5 degrees Longitude. Hellas Planitia is a crater several miles deep and over 1000 miles across. I believe Hellas Planitia was formed when an asteroid smashed into Mars. Naturally, like a bullet the asteroid tried to ram its way through the planet. It didn’t make it all the way through but it did produce a bulge called Tharsis, on the other side of the planet. Tharsis is around 6 miles high and over 2000 miles across. Like a bullet, the entry wound was smaller than the protuding exit wound. You can view a good Topography map of Mars with these two locations at http://ltpwww.gsfc.nasa.gov/tharsis/Mars_topography_from_MOLA/ The center of Tharsis is around -107.5 degrees Longitude and 25 degrees South. Tharsis is around 180 degrees from Hellas Planitia in an East West direction. However, the Latitude center
