A powerful new observatory is the best hope yet for finding the elusive Planet 9, a large planet that some scientists say is hidden in our solar system.

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

Jupiter is the largest planet in the solar system. It's about 11 times wider than Earth with an equatorial diameter of 88,846 ...

Till 2006, there were nine planets in the solar system. Pluto was the farthest planet from ... and 11 months for one orbit around the Sun and 9 hours, 56 minutes for one spin on its axis.

Almost 10 years ago, a NASA spacecraft was able to take several photos of Pluto, known for decades as a planet before it was ...

Pluto isn’t the only dwarf planet in our solar system's outer reaches. Now is an ideal time to look for the egg-shaped Haumea, says Abigail Beall ...

So far, the only evidence has come from some oddities in the orbits of small Pluto-like ... a way that the solar system can exist the way it does without there being a Planet 9." ...

A powerful new observatory is the best hope yet for finding the elusive Planet 9, a large planet that some ... at the far reaches of our solar system, there's an unseen giant planet.