Those most ancient Greenland “fossils” are not really life, new team says
Getting it right is important for the search for life on Mars: Found in 3.7-billion-year-old rocks in Greenland, the mounds strongly resemble cone-shaped microbial mats called stromatolites, researchers reported in 2016. But a new analysis of the shape, internal layers and chemistry of the structures suggests that the mounds weren’t shaped by microbes but by tectonic activity. The new work, led by astrobiologist Abigail Allwood of NASA’s Jet Propulsion Laboratory in Pasadena, Calif., was published online October 17 in Nature. … The debate highlights how important it will be to understand as much as possible about the geologic setting of a future Mars landing site, if scientists hope to spy evidence that there was once life there. It’s hard enough Read More ›