For the first time since Pluto was demoted, the idea of a true ninth planet is edging from speculation toward something testable. Instead of restoring Pluto, researchers are closing in on a different, ...

NASA's New Horizons spacecraft captured this high-resolution enhanced color view of Pluto that is inserted beneath the Short Wave logo. The image combines blue, red and infrared images taken by the ...

For decades, our solar system was thought to have nine planets, with Pluto considered the smallest and farthest. But in 2006, Pluto was officially reclassified as a dwarf planet by the International ...

Some of us remember August 24, 2006, like it was yesterday. It was the day Pluto got booted from the exclusive “planets club.” I (Sara) was 11 years old, and my entire class began lunch break by ...

Earlier this year scientists presented evidence for Planet Nine, a Neptune-mass planet in an elliptical orbit 10 times farther from our Sun than Pluto. Since then theorists have puzzled over how this ...

Earth has a newly-discovered neighbor in the solar system. But the heavenly body – possibly a dwarf planet à la Pluto – isn't a frequent visitor. Located beyond Neptune, its extreme orbit ...

Arizona Governor Katie Hobbs signed a law making Pluto the state's official planet. That's even though an international group of scientists stripped Pluto of its planetary status back in 2006, ...