“This the strongest evidence to date for a biological activity beyond the solar system,” says lead author ... this week in a ...

If the object really is Planet Nine, it would be larger than Neptune and exist 700 times further from the sun than Earth.

Vesta, thought to be the second-largest asteroid in the solar system, could be a piece of an ancient, unknown planet, a new study hints.

Astronomers have detected a promising sign of a ninth planet lurking at the the farthest reaches of the Solar System.

Using two infrared space telescopes and a 23-year gap, scientists may have spotted a mysterious, slow-moving object beyond ...

Pluto was discovered in 1930 in Arizona, but in 2006 scientists decided to cut Pluto from the planetary line up. Here is why ...

An international team including astronomers from the Center for Astrophysics | Harvard & Smithsonian (CfA) has announced the ...

Vesta might be a shattered remnant of an early planet, not a failed one—forcing scientists to rethink how worlds begin.

"This measurement of the planet population from planets somewhat larger than Earth all the way to the size of Jupiter and ...

"A planet orbiting not just a binary, but a binary brown dwarf, as well as being on a polar orbit, is rather incredible and ...

Once the quirky underdog of our solar system, Pluto held planetary status ... Here is everything to know about why Pluto is not a planet anymore. Pluto was downgraded cosmically in 2006 when ...