Pluto likely acquired large moon Charon in a “kiss and capture” collision billions of years ago. It may have created a subsurface ocean on the icy dwarf planet.

Charon is large in size relative to Pluto, and is locked in a tight orbit with the dwarf planet. A new simulation suggests how it ended up there.

The “demoted” dwarf planet Pluto and its largest moon Charon make an unusual pair, and for decades, scientists have been discussing how the binary system—in which each mutually orbits the other—came to be.

Everything you need to know about the full “Wolf Moon,” including exactly when, where and how to see it at its best from where you are, including an occultation of Mars.

Look for the January full moon to rise from the eastern horizon around sunset, according to NASA. By midnight, the wolf moon should glow bright and round overhead before disappearing at sunrise into the western horizon.