We're getting closer to the aliens. NASA's Mars Reconnaissance Orbiter has identified deposits of glass in the planet's craters. The feature might be common on the red planet, say new findings published in the journal Geology. If the glass is similar to what scientists on Earth have found, it may contain some lifeform from the moment it collided and formed in the heat impact. A crater containing the glass is near the potential landing site for the rover of the Mars 2020 mission.