On Aug. 24, 2006, the Worldwide Astronomical Union (IAU) determined that Pluto wasn’t a planet anymore.
Since that date, Pluto has been formally classified as a dwarf planet together with 4 different confirmed dwarf planets within the outskirts of the photo voltaic system.
This resolution sparked outrage around the world, and the controversy continues to be very a lot alive at present. Astronomers in favor of Pluto’s demotion argued {that a} planet by definition ought to have cleared its orbit across the solar. Pluto and the extra distant dwarf planets fail to fulfill this criterion.
Why it mattered
When Pluto was reclassified as a dwarf planet, many astronomers and scientists weren’t pleased with the end result.
“I am embarrassed for astronomy,” mentioned Alan Stern, chief of NASA’s New Horizon’s mission to Pluto and a scientist on the Southwest Analysis Institute. “Lower than 5 p.c of the world’s astronomers voted.”
Stern argued that in accordance with the IAU’s new definition, many different planets in our photo voltaic system would fail to fulfill the identical criterion. Earth, Mars, Jupiter and Neptune, for instance, all share their orbits with asteroids.
But when Pluto have been to maintain its planetary standing, lots of the photo voltaic system’s dwarf planets would additionally must be categorised as planets — and there may very well be a whole lot in our photo voltaic system.
Whereas astronomers proceed to debate the definition of planet and the implications thereof, the public has come together multiple times to defend Pluto’s title.
For now, Pluto will simply need to be the king of the dwarf planets. And that is fairly cool, too.
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