It's tough to put together a story to fit the geochemistry in the kind of scenario that they proposed. |
My view is that there is a good possibility there is life on Mars, probably in the subsurface. We know from examples on Earth that life can exist in extreme places, and Mars seems to have the necessary ingredients for that. |
Our study indicates it was probably more like parts of Yellowstone, Hawaii or Italy than something like the Great Salt Lake. We think it was far less favorable for past biological activity than other scenarios that have been proposed. |