The moon greets Jupiter two days ahead of its full moon phase on Feb. 1.

Add Yahoo as a preferred source to see more of our stories on Google. On Dec. 28, 2000, NASA’s Galileo spacecraft discovered auroras on Ganymede, Jupiter’s largest moon. Galileo launched in 1989 on a ...

Jupiter’s moon Ganymede could be a vast dark matter detector, and upcoming space missions might be able to spot distinctive dark matter craters on its ancient surface. Physicists searching for dark ...

That would make it thousands of times more massive than any moon orbiting a solar system plane  — so massive it could make ...

A new discovery suggests the possibility of an exomoon with an unprecedentedly large mass, thousands of times larger than any ...

Astronomers might not know what dark matter is made of, and they might not be able to see it, but they know that it exists.