Harvard scientists explain how Mars had warm spells billions of years ago, allowing rivers and lakes to exist.

"It's been such a puzzle that there was liquid water on Mars, because Mars is further from the sun, and also, the sun was ...

This NASA Mars Reconnaissance Orbiter image, acquired on May 13, 2018, during winter at the South Pole of Mars, shows a carbon dioxide ice cap covering the region and as the sun returns in the spring, ...

A U.S. scientist searching for a civilization across 7 Earth clones circling the red dwarf star TRAPPIST-1 says its own alien ...

And even that would be challenging. By Jonathan Corum The distance between Earth and Mars constantly shifts as they move around the sun, ranging from about 35 million miles to 250 million miles.

Mars' southern hemisphere absorbs a lot of the sun's energy during the Red Planet's spring, and that may be causing Mars' ...

Located less than 20 light years away, HD 20794d could potentially be one of the most Earth-like planets found so far, ...

Earth is home to some truly bizarre and breathtaking landscapes — here are 20 that look straight out of an alien world.

The Mars Sample Return mission has been ranked as the highest priority by planetary scientists, who hope to find signs of ancient life on Mars.

On Sunday (Jan. 12), the Red Planet will make its close approach of Earth at 8:32 a.m. EST (13:32 GMT). This event, known as ...

Within a few minutes, Mars rose farther above the Moon's horizon. Thanks to the parallax effect, the Moon's relative motion in its orbit around Earth appears significantly faster than the movement ...

The northern plains of Mars, marked by thousands of mounds and hills, hold significant evidence of the planet's watery past.