The simulation of the Solar System that came the closest to the observation was the presence of a small planet, between the ...

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 investigating a potential hidden planet, dubbed Planet Y, far beyond Neptune. Its gravitational pull is ...

(CNN) — The search for an unknown planet in our solar system has inspired astronomers for more than a century. Now, a recent study suggests a potential new candidate, which the paper’s authors have ...

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 ...

What do you do when you encounter a strange astronomical event, a collection of data from planets thousands of light-years ...

Voyager 1 has been exploring the cosmos for decades, but when it reached the edge of the solar system, it found something ...

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

The European Southern Observatory said the discovery as "the first clear detection of a baby planet in a disc with multiple rings" Abigail Adams is a Human Interest Writer and Reporter for PEOPLE. She ...

This article was originally featured on The Conversation. 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 ...