The fact that the cold, dry Mars of today had flowing rivers and lakes several billion years ago has puzzled scientists for ...

A super-Earth planet that dips in and out of its star's habitable zone has been discovered just 19.7 light-years away.

The fact that the cold, dry Mars of today had flowing rivers and lakes several billion years ago has puzzled scientists for decades. Now, Harvard researchers think they have a good explanation for a ...

Mars, Venus, Jupiter and Saturn should be visible to the naked eye, but get a telescope and you can spot Neptune and Uranus.

Four planets will be in the parade in January, while seven will align in February. Here's how to see the events.

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

ESA is revolutionizing access to Mars with its LightShip initiative, focusing on small, cost-effective spacecraft. This new ...

The case of mistaken identity was quickly resolved, but astronomers say it shows the need for transparency around craft in ...

The car-sized Curiosity rover has spotted evidence of once quite hospitable environs on Mars.

While planets circle the sun in what's called a heliocentric orbit, they rarely fall together in what appears to the human eye as somewhat of a line across the visible horizon. Saturday is one of ...