Little is known about the long-destroyed moon-forming planet, Theia. But it may have been born in the inner solar system—just like Earth—a new study suggests ...

When a meteor streaks across the sky, it's not just beautiful. It's nature's way of delivering a time capsule to Earth.

Astronomers measure the speed at which the solar system is hurtling through space by mapping surrounding galaxies and ...

Scientists believe the moon was formed from the debris of a collision between Earth and the planet Theia, which was likely ...

Scientists believe the moon was formed from the debris of a collision between Earth and the planet Theia, which was likely located closer to the sun than Earth is now.

NASA unveiled close-up pictures on Wednesday of the interstellar comet that's making a quick one-and-done tour of the solar ...

Explore the vastness of the Solar System in this video, which accurately showcases the relative sizes of the planets and ...

Bundle up and blast off to the far reaches of our Solar System for Ice Giant Night at the historic Cincinnati Observatory.

About 4.6 billion years ago, a celestial cloud collapsed, paving the way for our solar system to form. Then, a nebula with strong gravitational pull took shape, kick-starting the birth of the sun. But ...

LONDON — 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 ...