Present-day Mars is a world both familiar and alien. Like Earth, Mars has mountains and valleys, sand dunes and ice caps, clouds and dust bunnies. But on Mars there is no sign of active plate tectonics, no sign of long-lived surface water, and, perhaps most intriguingly, no definitive sign of life.
Like a mechanical Sherlock Holmes, the Curiosity rover has been looking for clues that will bring us answers about Mars's past and present. Curiosity's recent confirmation of methane in Mars's atmosphere has piqued my interest. What is its source—biology or geology? And what's responsible for its mysterious temporal variability?
I was part of two Keck Institute for Space Studies workshops dedicated to unraveling the mystery of methane on Mars, which culminated in a comprehensive review paper led by my PhD advisor, Professor Yuk L. Yung.
Image credit: NASA/JPL/University of Arizona
