German astronomer Simon Marius is best remembered for his disputes with Galileo Galilei over priority for discovering Jupiter ...

As a moon, Callisto is the most boring of the four. Is surface is carpeted by ... The star of the show this month is Jupiter (see main story), second in brightness only to Venus and visible ...

December's full moon, the "Cold Moon," rose in a blaze of color on Sunday night as the year’s final supermoon.

Weather permitting, Jupiter will not only be brighter than most other stars and planets in the evening sky, but will also be ...

The new moon of December occurs tonight. A day later, Southern Hemisphere observers will see the peak of the Phoenicid meteor ...

The Geminid meteor shower​ will be peaking Friday and Saturday night in Boston and will be visible in the sky.

NASA and ESA’s Hubble Space Telescope has been observing the outer planets through a program called OPAL (Outer Planet ...

The four "Galilean moons" were named after Italian astronomer Galileo Galilei, who is thought to have discovered them in 1610. As night falls, Jupiter ... of Canis Major, Procyon in the ...

Clouds produced an incredible lunar halo that was widely seen in the D.C. area Friday night. Depending on cloud cover, there ...

The Geminid meteor shower is due to peak on December 13, but there's plenty of other celestial sights to feast your eyes on ...

I pick out North America’s celestial highlights for the week ahead (which also applies to northern hemisphere mid-northern ...