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 ...

For many people, the definition of a planet was only made clear in 2006, when the spunky world Pluto was demoted from a planet to a dwarf planet. Now, a team of astronomers is pushing for “planet” ...

Two decades after Pluto was reclassified as a dwarf planet, scientists remain divided over the definition that removed it from the solar system’s traditional list of planets. The disagreement comes ...

Twenty years after Pluto lost its planetary status, the debate continues as scientists still disagree over what defines a planet.

Planetary scientists are proposing a new definition of a planet to replace one that many researchers view as sun-centric and outdated. The current definition—established in 2006 by the International ...

This story is part of Short Wave's series Space Camp about all the weird, wonderful things happening in the universe. Check out the rest of the series. If you were born in the last century you might ...

Astronomers found a massive object orbiting a brown dwarf star. This discovery challenges existing definitions of planets and ...

Alfredo has a PhD in Astrophysics and a Master's in Quantum Fields and Fundamental Forces from Imperial College London. Alfredo has a PhD in Astrophysics and a Master's in Quantum Fields and ...

The International Astronomical Union defines a planet as a celestial body that orbits the sun, is massive enough that gravity has forced it into a spherical shape, and has cleared away other objects ...

The International Astronomical Union defines a planet as a celestial body that orbits the sun, is massive enough that gravity has forced it into a spherical shape, and has cleared away other objects ...