Search for fossils Archives

November 22, 2021November 22, 2021 by Evan Gough

Is That a Fossil on Mars? Non-Biological Deposits can Mimic Organic Structures

NASA's Perseverance rover, which is searching signs of ancient life on Mars. Some of the rocks in this image are volcanic in origin. (credit: NASA/JPL-Caltech/MSSS)

There’s nothing easy about searching for evidence of life on Mars. Not only do we somehow have to land a rover there, which is extraordinarily difficult. But the rover needs the right instruments, and it has to search in the right location. Right now, the Perseverance lander has checked those boxes as it pursues its mission in Jezero Crater.

But there’s another problem: there are structures that look like fossils but aren’t. Many natural chemical processes produce structures that mimic biological ones. How can we tell them apart? How can we prepare for these false positives?

November 13, 2019November 13, 2019 by Evan Gough

Mars 2020 Rover is Going to a Place on Mars That’s Perfect for Preserving Fossils

Jezero Crater on Mars. Lighter colors represent higher elevations. The Mars 2020 rover will investigate the "bathtub ring" of carbonates around the edge of the crater for microscopic fossils. The dark oval is the landing ellipse. Image NASA/MRO

Back in November 2018, NASA announced that the Mars 2020 rover would land in the Jezero Crater. Jezero Crater is a geologically diverse area, with an alluvial fan of sediment deposited by an incoming river. That sediment may contain preserved ancient organic molecules, and the deposit is clearly visible in satellite images of the Crater.

But the crater holds something else that has scientists intrigued, something that doesn’t show up so clearly in visible light images: a “bathtub ring” of carbonates, which scientists think could hold fossils.