Are planets in the solar system that are closer to the Sun older than the ones further away? – Gavriel, age 10, Paducah, Kentucky A cloud of collapsing gas created our Sun, the first thing to form in ...

Pluto was reclassified as a dwarf planet in 2006. Our solar system may have a ninth planet after all, researchers say. The possibility that an additional planet may be hidden far into the solar system ...

On August 24, 2006, our solar system lost a planet. It wasn't by cataclysmic destruction, but rather by the vote of the International Astronomical Union, which declared that Pluto, considered the ...

All of our solar system’s planets are lining up to parade through the night sky at once. This extraordinary celestial event will see the sky scattered with seven visible planets in what is known as a ...

From lava worlds to gas giants, NASA says the variety of these worlds is staggering—and that signs of a further 8,000 distant ...

A new study suggests yet another theory for a possible extra planet in our solar system, likely of a size between Mercury and ...

Astronomers have discovered fresh evidence suggesting the possible existence of an unseen planet in the far reaches of our solar system.

Astronomers have discovered seeds of rocky planets forming in the gas around the baby sunlike star providing *** peek into the start of our own solar system. The the thing that we've discovered is ...

Our solar system is a smashing success. A new study suggests that from its earliest period—even before the last of its ...