Astronomers have picked up evidence of an Earth-sized world, distinct from the previously hypothesised Planet Nine and Planet ...

The solar system has many more moons than the one we can see in the sky. But how many do we actually know about? And how many ...

Astronomers propose a new hypothetical planet, Planet Y, beyond Neptune, based on observed orbital anomalies in the Kuiper ...

On Aug. 24, 2006, the International Astronomical Union (IAU) decided that Pluto wasn't a planet anymore. Instead, Pluto is ...

You know, if you think about it, and trust me we're about to, the moon is kind of weird. Of all the terrestrial worlds of the ...

Pluto, once considered the ninth planet of our solar system, has been a topic of intrigue since its reclassification as a ...

The debate over Pluto’s planetary status has been ongoing since its reclassification as a “dwarf planet” in 2006 by the ...

A study suggests an Earth-sized planet, dubbed Planet Y, may exist beyond Neptune, affecting the orbits of icy objects in the ...

On August 24, 2006, Pluto ceased to be considered a planet. A mixture of rock and ice located in the Kuiper Belt, a region of icy objects beyond the orbit of Neptune. This demotion ...

Planet Nine was previously suggested as a possible explanation for distant orbital clustering. It was thought to be ten times Earth’s mass, orbiting far beyond Neptune.

Phases of ice that exist naturally only on frozen moons could be detected using infrared spectroscopy, according to new ...

As NASA grapples with major proposed budget cuts and losing some of its most brilliant minds, America’s willingness to look ...