Skywatchers will witness a rare event as the Moon, Mars, and Mercury appear close together in the twilight sky this October.

The 6%-lit waxing crescent moon will be visible roughly 5 degrees above the horizon as the sun sets on Oct. 23, with Mercury ...

Due to the opposing perihelion alignment, the comet won't be generally visible until November, emerging low above the horizon ...

Mars is an inhospitable desert planet. Billions of years ago, things were different. In Jezero Crater, for example, fed by a ...

Stargazers have had a lot to smile about over the past few weeks. Only a few days ago, five planets aligned in the pre-dawn sky. With the summer solstice on the horizon, a pair of planets will line up ...

When Earth is opposite Mars from the sun, it will appear full because you’re looking directly on the daylit side. But ...

A new analysis of chemical signatures measured by NASA's Curiosity Rover gives a peek at Mars's past to a time some 3.7 ...