Rocky exoplanets are indicated to be common in the galaxy. Future instruments including the {\it James Webb Space Telescope} (JWST), high resolution ground-based spectrographs, and direct imaging missions for under consideration by the 2020 Decadal Survey on Astronomy and Astrophysics are poised to unlock the atmospheres of habitable zone planets...
If life exists on Mars, it likely resides in a deep subsurface environment. The Martian rocky subsurface is a primary target for the search for extraterrestrial life because it offers a stable habitat for microbial life. On Earth, the continental subsurface is a key astrobiological analog for understanding what properties...