The small world was found during a search for the hypothetical Planet Nine, and astronomers say the next time it will reach ...

Earth has a new neighbor that lives far, far away. Scientists from the Institute for Advanced Study's School of Natural ...

As it orbits the sun once every 25,000 years, the celestial body 2017 OF201 travels beyond the Kuiper Belt into a region ...

NASA's Perseverance rover is exploring a new Mars region called Krokodillen, which is thought to harbor some of the oldest and most intriguing rocks on the Red Planet.

It's an evocative idea that has long bedeviled scientists: a huge and mysterious planet is lurking in the darkness at the ...

Our solar system’s origin story spans billions of years and involves clouds of gas, cosmic collisions, and planetary ...

In the cold, dark outskirts of planetary systems far beyond the reach of the known planets, mysterious gas giants and ...

Scientists are intrigued after spotting a highly unusual celestial object lurking at the very edge of our solar system.

The fundamental building blocks for planet formation can exist even in environments with extreme ultraviolet radiation, according to a new study.

This solar cycle still ... that surrounds our planet and deflects much of the most dangerous emissions. The risks of solar activity stretch throughout the solar system, however.

but both men previously suggested a “Planet X” existed in the far reaches of the solar system. “It’s kind of fun that a paper that purports to find a candidate for Planet Nine is really ...

A new batch of 65 planets located outside our solar system joined the NASA Exoplanet Archive, triggering a celebratory mood. "It's not just a number," Exoplanet Archive science lead Jessie ...