Free Astronomy Magazine July-August 2018

24 ASTROBIOLOGY The search for life on Mars produced exciting new results thanks to the work of NASA's Curiosity rover. The collected data reveal the presence of organic compounds on the surface of the planet and a mysterious sea- sonal variation in the concentration of methane in Gale Crater. A basis for these observations could involve biological or geochemical processes. What will the reality be? Two top-level discoveries by Curiosity di Michele Ferrara by i l revised by Damian G. Allis NASA Solar System Ambassador JULY-AUGUST 2018