Are we alone? The interstellar search for alien life

Astronomers searching for planets outside our solar system discovered the tiniest one yet in late February — one that’s about the size of our moon. But the new world, known as Kepler-37b, orbits too close to its sun-like star and is too sizzling to support life. Its surface temperature is an estimated 700 degrees Fahrenheit. It also lacks an atmosphere and water on its rocky surface.

NASA/AMES/JPL-CALTECH