Life On Mars?

 A mudstone sample was taken from Mars's Gale crater. This rock was billions of years old, from what may have been an old lake. A location with conditions for life. Mass spectrometry revealed the long-chain ketanes, decane, undecane and dodecane, in the rock. They have respectively 10, 11 and 12 carbons. Such molecules can be produced by abiotic (non-living ) processes. On Earth, however, they are generally breakdown products of fatty acid components of membranes around and within cells. On contact with water, these phospholipids (fats with a phosphate group) self-assemble into bilayers. These double membranes, control what goes into and what leaves cells (https://pubmed.ncbi.nlm.nih.gov/40127274/). These mudstone ketanes are longer than others found elsewhere on Mars. The evidence isn't, by any means, definitive but it suggests that, billions of years ago, there could have been life on Mars.