These icy bodies orbit the sun just like the major planets, yet they follow their own rules, often traveling along elongated ...

"It's very rare to discover an object both large and with an exotic orbit." When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. A potential new dwarf ...

Right above you is the sky – or as scientists would call it, the atmosphere. It extends about 20 miles (32 kilometers) above the Earth. Floating around the atmosphere is a mixture of molecules – tiny ...

Ammonite was discovered using the Subaru Telescope in Hawaii, with follow-up confirmation from the Canada-France-Hawaii Telescope. Its orbit and size officially qualify it as a distant dwarf planet.

It's an evocative idea that has long bedeviled scientists: a huge and mysterious planet is lurking in the darkness at the edge of our solar system, evading all our efforts to spot it. Some astronomers ...

After studying thousands of computer simulations of the solar system, researchers at Rice University and the Planetary Science Institute think there’s a 40% chance an elusive “Planet Nine” or “Planet ...

Jupiter, king of our solar system’s planets, continues to dominate the night sky in February. Lying inside the zodiac ...

On03, NASA's Pioneer 10 spacecraft beams its last data transmission back to Earth. Pioneer 10 was NASA's first mission to the ...

Astronomers are closing in on one of the most tantalizing possibilities in planetary science, evidence that a previously unknown world may be lurking in the outer reaches of the solar system. The ...

There may be a warp in the Kuiper Belt, possibly caused by “Planet Y” — a Mercury-to-Earth-sized world that orbits the sun way beyond the orbit of Neptune. Is there a mysterious “Planet Y” orbiting ...