Martian Chemical May Put Slight Doubt on Possibility of Life

A week after confirming that the Mars Phoenix Lander had discovered ice in the Martial soil, NASA scientists announced that it may have uncovered something else—perchlorate, a type of organic salt that had never been found on Mars before. At a press conference on Tuesday, researchers said the find raises a number of questions about Martian geochemistry, particularly about the flow of water on the planet. But they said its discovery will likely have little bearing on the key question of whether or not Mars might be able to host life [New Scientist]. Some had worried that the presence of perchlorate would preclude the possibility of life on Mars because these chemicals are hazardous to humans and many other animals. But they aren't dangerous to all life; in fact, certain organisms depend on them—in Chile's Atacama Desert, some microbes use oxygen from naturally occurring perchlorate for energy [Science News]. Though ...