Astronomers have discovered a mysterious dwarf planet, 2017 OF201, far beyond Pluto. This discovery challenges existing ...

Cheng, together with graduate students from Princeton University, discovered the potential dwarf planet while searching for ...

Breakthroughs, discoveries, and DIY tips sent every weekday. Terms of Service and Privacy Policy. Almost a decade after astronomers proposed the existence of Planet 9 ...

Scientists examined infrared space surveys to narrow down candidates for Planet 9. Planet 9 would be so far from the Sun that it is just not illuminated by much sunlight. The two space surveys ...

We have discovered thousands of exoplanets in the last few decades, while the number of planets in the Solar System has remained at eight – but our discovery of more might not yet be over.

Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. Our solar system ...