Pluto... we miss you!
I sincerely hope Pluto can clear it’s orbit of random objects so it can once again be our 9th planet. It’s just not the same without him.
31-35, F
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DrWatson · 70-79, M
Here is the history. We have been discovering more and more objects beyond Pluto. Most of them are small, but some are of respectable size. And one in particular is bigger than Pluto.
So that prompted scientists to question the use of the word "planet". Are all of these things going to be called planets?
Everybody waited until the discoverer of Pluto, Clyde Tombaugh, died. And then, the International Astronomical Union declared that to be a planet, an object must satisfy three conditions: one, it must orbit the sun; two, it must have enough mass that its gravity has shaped it into roughly spherical form (there are a lot of small asteroids out there with very weird shapes); and three, it must have enough gravity that it has swept its orbit free of orbiting debris. Pluto fails the third test.
So Pluto has been renamed a "dwarf planet". The asteroid Ceres, which is the largest of the asteroids, also became a dwarf planet.
But planetary scientists, the one who study the geography, the atmospheres, the chemistry, and the possible biology of planets, do not care about this third criterion at all. Many still call Pluto a planet.
And what about that large far-off object beyond Pluto that caused all this chaos? It has been named Eris, after the goddess of discord!
(In Greek mythology, she tossed an apple into a room with a tag on it saying "to the fairest". The goddesses Athena, Aphrodite, and Hera argued about who it should go to, and eventually that led to the Trojan War!)
So that prompted scientists to question the use of the word "planet". Are all of these things going to be called planets?
Everybody waited until the discoverer of Pluto, Clyde Tombaugh, died. And then, the International Astronomical Union declared that to be a planet, an object must satisfy three conditions: one, it must orbit the sun; two, it must have enough mass that its gravity has shaped it into roughly spherical form (there are a lot of small asteroids out there with very weird shapes); and three, it must have enough gravity that it has swept its orbit free of orbiting debris. Pluto fails the third test.
So Pluto has been renamed a "dwarf planet". The asteroid Ceres, which is the largest of the asteroids, also became a dwarf planet.
But planetary scientists, the one who study the geography, the atmospheres, the chemistry, and the possible biology of planets, do not care about this third criterion at all. Many still call Pluto a planet.
And what about that large far-off object beyond Pluto that caused all this chaos? It has been named Eris, after the goddess of discord!
(In Greek mythology, she tossed an apple into a room with a tag on it saying "to the fairest". The goddesses Athena, Aphrodite, and Hera argued about who it should go to, and eventually that led to the Trojan War!)