NASA’s Perseverance rover has identified complex macromolecular carbon on the surface of a rock in Jezero Crater. The detection at the Bright Angel outcrop represents the shallowest such finding on Mars to date.
The rover used its SHERLOC instrument to examine targets at the edge of an ancient river channel called Neretva Vallis. Between sols 1180 and 1218, three rocks named Cheyava Falls, Apollo Temple, and Walhalla Glades showed a graphitic band signal indicating the presence of the carbon material. A fourth rock, Steamboat Mountain, served as a control and produced no such signal.
Researchers ruled out instrument artifacts and Earth contamination as sources of the signal. Ashley E. Murphy, lead author of the study, noted that the material roughly matches terrestrial kerogen yet is described as macromolecular carbon to avoid implying a biological origin.
The carbon appears linked to at least two separate geologic events, one involving sediment burial and another involving groundwater movement that deposited carbonate and sulfate minerals. Kyle Uckert of NASA’s JPL confirmed the signal originated from the rocks themselves.
Kevin P. Hand, Perseverance principal investigator at JPL, stated that instruments on Earth will be needed to determine whether the carbon has biotic or abiotic origins. Samples collected by the rover may eventually provide that analysis.
