Our solar system may have a ninth planet after all, following the declassification of Pluto nearly two decades ago, ...

Earth has four seasons, but do other planets in our solar system also have hot summer days and cold winter nights?

At the center is the sun, a yellow dwarf star that contains 99.8% of the solar system's mass. Everything else — from the eight major planets to dwarf planets, comets, asteroids, and icy objects ...

A new look through decades-old data has unveiled some of the most compelling evidence yet of a hidden ninth planet in the far ...

Caroline Delbert is a writer, avid reader, and contributing editor at Pop Mech. She's also an enthusiast of just about ...

A planet circling at a sharp 90-degree angle to the orbits of its two host stars has now been confirmed. This discovery ...

Astronomers may have found a candidate for Planet Nine. This planet is beyond Neptune. The finding could be the first ...