At 4 billion miles away from the sun, Arrokoth is 'too cold to support life as we know it', NASA says. But the new findings ...

Arrokoth is composed of two separate bodies, 3 and 9 miles across. In the distant past they rotated so slowly about each other that their mutual gravitational attraction caused them to come together ...

The larger moons of Pluto and Earth likely formed through a collisional process with Charon and our moon, respectively, ...