Over the past decade or so, astronomers have speculated about the characteristics of rogue planets in the Milky Way galaxy. These "free-floating" worlds don't orbit stars, but instead roam the ...

There's no shortage of round celestial objects in our universe. Planets, moons and stars all exhibit lovely spherical shapes.

senior research scientist David Bennett of NASA’s Goddard Space Flight Center, in a press release. “This is the first measurement of the number of rogue planets in the galaxy that is sensitive ...

Previous findings suggested that most of these planets were about the size of Jupiter, our solar system’s most massive planet. But that conclusion garnered a lot of pushback; even scientists who ...

Today, it’s believed that Jupiter and Saturn, the largest planets, were the first to fully form, both within a few million ...

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

Astronomers have discovered a rare in-sync solar system with six planets moving like a grand ... explain how solar systems across the Milky Way galaxy came to be. This one is 100 light-years ...

Learn how a possible ninth planet, the theoretical Planet X, could have acquired its wide orbit in the outer Solar System - a ...

Warmer climates than Earth’s could accelerate life’s development, potentially increasing the number of planets with more ...

More than 5,000 planets exist beyond our solar system, according to NASA, and this week astronomers announced they may have discovered the youngest one yet. Scientists using the Atacama Large ...

A team of astronomers believe they may have discovered a new dwarf planet—just like Pluto—on the edge of our solar system.