A mysterious moon, a vanished Soviet spacecraft, and monolith-like objects standing alone in the Martian dust—what’s really ...

One summer night in 1877, American astronomer Asaph Hall was looking through his telescope in Washington, D.C. Mars was at ...

More study the Martian moons Phobos and Deimos. The mission should contain a sample return component, and after collecting material from Phobos in 2024, should return that component to Earth in ...

The origin of Phobos and Deimos, the two Martian moons, has been a mystery to astronomers. These two bodies are a fraction of the size and mass of the Moon, measuring just 22.7 km (14 mi) and 12.6 ...

"Studying Phobos’ orbit also allows scientists to refine predictions of when the doomed moon will crash into Mars," according to NASA. Eric Lagatta covers breaking and trending news for USA TODAY.

Phobos has the closest orbit of any known moon to its parent body, circling the red planet at a distance of just 6,000 kilometers (3,700 miles), ...

Previously unpublished photos of Mars' moon Phobos hint that the mysterious satellite may actually be a trapped comet — or perhaps just a piece of one, along with its twin moon Deimos.

The Martian moon Phobos orbits only a few thousand miles above the Red Planet's surface. Its proximity to its planet is one of the reasons astronomers were unable to see the satellite until the ...

Phobos is also bright enough to spot at times during the day. Deimos orbits about four times farther from Mars than Phobos does and appears roughly 2.5′ across ...

Phobos-Grunt (Phobos is one of Mars' two moons; Grunt is Russian for ground) had an ambitious mission -- to orbit Mars, land on Phobos, scoop up a soil sample, and bring it home for study.