Free Astronomy Magazine January-February 2020

47 JANUARY-FEBRUARY 2020 ASTRONAUTICS T his artist con- cept and the side video show the Mars Helicop- ter, a small, au- tonomous rotor- craft that will travel with NASA’s Mars 2020 rover mission to demon- strate the viabil- ity and potential of heavier-than- air vehicles on the red planet. [NASA/JPL-Caltech] for the rover to explore,” added Jesse Tar- nas, a Ph.D. student at Brown University and the study’s lead author. Among the hydrated silica deposits known today, there is one that should be easily ac- cessible to the rover, being at low elevation in the river delta. Given the position of this deposit, it is possible that it is part of the bottommost layer of the delta itself, an ideal sce- nario for the preserva- tion of any clues of past life, as recalled by Jack Mustard, a professor at Brown and study co-au- thor: “The material that forms the bottom layer of a delta is sometimes the most productive in terms of preserving biosignatures. So if you can find that bottomset layer, and that layer has a lot of silica in it, that’s a double bonus.” Carbonate distribution is equally interest- ing. A recent work published in November in the journal Icarus (Briony H.N. Horgan et al., 2019) highlighted concentrations of carbonates that seem to draw shorelines within Jezero Crater, as if to indicate the level of water that filled the crater for a long period of time. On our planet, scenar-