New research suggests that a binary pair of Kuiper Belt objects, known as the Altjira system, is actually made up of three ...

The ringed gas giant Saturn has officially replaced Jupiter as the planet in our solar system with the most moons. The ...

For decades, Pluto was celebrated as the ninth planet of our solar system. However, in 2006, the International Astronomical Union (IAU) redefined what constitutes a planet, leading to Pluto’s ...

The controversy endures over Pluto's true status ... Uranus and Neptune, the most recently discovered planets in the solar system at the time, seemed out of sorts. Their orbits didn't add up ...

For decades after the first eight planets were barnstormed, orbited, and landed upon by spacecraft from Earth, Pluto remained the only one of the solar system’s major worlds that never received ...

Here's what to know about the short life of what was, for a single human lifetime, the solar system's smallest planet. Pluto was discovered in 1930 by Clyde Tombaugh, an American astronomer at the ...

Now, other states may roll back law Why Pluto isn't part of any planet parades For those people still scratching their heads, trying to figure out why the solar system has fewer planets now than ...

Discovered in 1930 at Lowell Observatory in Flagstaff, Arizona, Pluto was hailed as the ninth planet in our solar system. For decades, it captivated imaginations with its icy surface and distant ...

FLAGSTAFF, Az. – Whether Pluto is officially a planet is the least interesting thing about the runt of the solar system, astronomers will tell you 95 years after the discovery of the fascinating and ...

Pluto was once the ninth planet of our solar system, until scientists reclassified it in 2006, sparking outrage and debate.

This phenomenon known as a "planet parade," will feature Mercury, Venus, Mars, Jupiter, Saturn, Uranus and Neptune all ...