THE Mars rover Opportunity discovered last week that surface water existed on early Mars not just for years but for aeons, making it more likely that life had enough time to get a foothold on the planet.
Within a few weeks of landing on Mars in January, Opportunity found evidence of a watery past on the surface of Mars, first in a small crater called Eagle near its landing site Meridiani Planum, and then in the much larger Endurance crater. In both places, the layered bedrock provided multiple lines of evidence, including voids left by dissolved salt crystals, and haematite…
