In the remote outer reaches of planetary systems, far beyond the orbit of known planets, enormous and mysterious worlds silently loop around their stars. Some drift as far as 10,000 times the distance ...

Astronomers are closing in on one of the most tantalizing possibilities in planetary science, evidence that a previously ...

The newly identified cluster of Kuiper Belt objects lies about 4 billion miles from the Sun, offering fresh clues about how ...

There have been questions about a mysterious ninth planet in our solar system for nearly a decade. Pluto was unseated as number nine in 2006. Now, a group of international researchers say they may ...

Is there a massive undiscovered planet on the outer reaches of the solar system? The idea has been around since before the discovery of Pluto in the 1930s. Labeled as planet X, prominent astronomers ...

The researchers said 2017 OF201 was identified in observations by telescopes in Chile and Hawaii spanning seven years. Scientists have identified an object about 435 miles (700 km) wide inhabiting the ...

A tiny meteorite is rewriting what scientists thought they knew about the origins of our solar system. New evidence found in shavings from a meteorite known as Northwest Africa 12264 — a 50-gram (1.8 ...

New observations suggest that the dwarf planet Makemake is surrounded by faintly glowing methane gas. Scientists are unsure if the gas is contained within a wispy atmosphere or being ejected into ...

Most planet-forming disks have warps that can lead to planets on inclined orbits, which could explain where the tilt of Earth's orbit came from. When you purchase through links on our site, we may ...