In 2006, the International Astronomical Union (IAU) voted on the definition of a planet. Famously, Pluto no longer met the criteria and was demoted to a dwarf planet. Things have been a bit of a mess ...

Once the quirky underdog of our solar system, Pluto held planetary status until 2006, when it got a cosmic demotion that still stings space fans. Discovered in 1930, Pluto was the ninth planet for ...

The year was 2015. After traveling billions and billions of miles through the Erebus, New Horizons encounters the boatman, and the somber lord of the departed. The spacecraft could have been called ...

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 ...

The new definition from the IAU states a planet much possess three criteria: 1) It needs to orbit a star, 2) Its size must result in enough gravity to form it into a spherical shape, and 3) Its size ...

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 ...

James is a published author with multiple pop-history and science books to his name. He specializes in history, space, strange science, and anything out of the ordinary.View full profile James is a ...

Deep in the outer solar system, billions of miles from Earth, lurks a realm of small, icy worlds called dwarf planets. Astronomers know relatively little about these dim and distant objects, but in ...

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Our solar system officially houses eight planets, but some scientists say there could be a ninth. And that’s not just Pluto aficionados – evidence suggests a huge undiscovered world lurks on the dark ...

The New Horizons Pluto flyby revealed unexpectedly complex geological features on dwarf planets, prompting further investigation into the diversity within the Kuiper Belt. Several dwarf planets, ...