2007-05-28 05:09:01 · 32 answers · asked by sharpie2292 3 in Science & Mathematics ➔ Astronomy & Space
Pluto has not been bewitched and made invisible in the latest Harry Potter blockbuster, Nor has it exploded. Nor has it imploded. Nor has it been towed away to a planet pound in Alpha Centauri. It has not altered its physical shape or temperature or orbit in any way. It is still very much here. Where it always was,
Presumably you have heard a statement to the effect that it is no longer a planet, or more misleadingly, that it is no longer part of our Solar System (which is simply not true).
What happened was that in August 2006 the International Astronomical Union (IAU) held a Congress in the Czech capital Prague, at which, after much debate, a motion reclassifying Pluto as a Dwarf Planet (a new category) was passed.
It is joined in that new category by the biggest of the asteroids between Mars and Jupiter, called Ceres and by the newly-discovered Eris (previously known as Xena) which orbits in the Scattered Disk, an area of the Solar System that is further out than the Kuiper Belt where Pluto resides.
The basic reasons for the decision are twofold:
(a) Pluto proves to be much smaller than was first thought on discovery in 1930. Much of the mass it was believed to have was actually its moon Charon, discovered 1978. Pluto is smaller than our own moon, smaller than the 3 biggest moons of Jupiter (Ganymede, Callisto and Io) and smaller than the largest moon of Saturn (Titan)
(b) We now know of some 800 or more objects in the Kuiper Belt which have been discovered in the last 20 years. It is clear that Pluto is simply the largest of twenty or more similar objects, If it remained a planet, their case for inclusion as planets would be hard to argue against. It was thought that having such a large number of planets was getting silly.
This has happened before. When Ceres was first discovered in 1801 it was immediately hailed as a planet. Three more similar objects were then found (Vesta, Juno and Pallas) in 1802, 1804 and 1807. They too were given planetary status. But then there were no further such discoveries for another 45 years and it looked like they were the only ones of their kind.
But then new discoveries started to flood in. There were at one point in the 1850s 23 recognised planets, 15 of them like Ceres. but realising these were just the tip of an iceberg and there were a lot more similar objects about to be discovered, the concensus was to demote these 15 objects and call them asteroids. Which is what they did.
Just as well they did, really, because there were over 100 of them by 1868. 400 of them by the turn of the century and we now know of some 360,000 of them, with new ones being found at the rate of 5,000 a month.
Meanwhile NASA has launched the New Horizons probe which will rendezvous with Pluto and Charon on July 14th 2015. the first probe to ever be sent to Pluto, and we should learn a lot more about Pluto and its 3 moons when it gets there. NASA would hardly spend $650,000,000 dollars on this mission if Pluto wasn't there, would it?
You can follow the probe's adventures on its official NASA web site (3rd link).
2007-05-28 05:12:15 · answer #1 · answered by Anonymous · 1⤊ 0⤋
Does it ACTUALLY matter? You can't even see Pluto without a very powerful telescope. If Pluto is a planet, so is Charon, Ceres and numerous other bodies in the solar system. Pluto was only originally classed as a planet because astronomers thought that Pluto and Charon were both Pluto, making it about the same size as Mercury.
2016-04-01 00:56:41 · answer #2 · answered by ? 4 · 0⤊ 0⤋
Pluto had been identify as a dwarf planet as of 2005 so there are only 8 planets in our Solar System right now.
2007-05-28 05:11:49 · answer #3 · answered by ngantran1993 1 · 0⤊ 0⤋
Well. It is angry at the shabby treatment it is receiving: "dwarf" indeed! Ever heard of "mass challenged" or "gravitationally challenged"? What is wrong with those people? Anyway, I hear that it is in secret talks with Alpha Proxima to become a full planet again in THAT solar system.
I guess, until we hear the official word from them we should assume that decisions by a bunch of geeks here on Earth won't have any immediate effects at changing which star Pluto orbits.
2007-05-28 05:24:51 · answer #4 · answered by Anonymous · 0⤊ 0⤋
Of course Pluto is still in the solar system. It has been downgraded from planet to Kuiper Belt object for having an orbit that passes within that of Netpune and for there being other bodies of comparable size and orbital radius (re Bode-Titus law for planets) Quaoar, Sedna Orcus, Varuna....
2007-05-28 05:18:51 · answer #5 · answered by Uncle Al 5 · 0⤊ 0⤋
Okay, so my 11 year old son who loves science said it is in our solar system, but it is not a planet. There are only 8 planets now. This comes from what is being taught to the elementary school kids in California.
2007-05-28 05:13:18 · answer #6 · answered by Victoria S 2 · 0⤊ 0⤋
Pluto is still considered part of our solar system, however it is simply not given the status of planet anymore.
"The researchers said Pluto failed to dominate its orbit around the Sun in the same way as the other planets."
Therefore, now it is simply a "dwarf planet."
2007-05-28 05:13:06 · answer #7 · answered by tricolore_21 2 · 1⤊ 0⤋
No pluto left to find another solar system that would accept it for the planet it was meant to be
2007-05-28 05:13:25 · answer #8 · answered by 'lil peanut 6 · 0⤊ 0⤋
It is, but recently scientists have changed the criteria for being a planet.
Pluto does not meet the newly accepted criteria, and is no longer considered a planet.
2007-05-28 05:12:41 · answer #9 · answered by No Chance Without Bernoulli 7 · 0⤊ 0⤋
Yes But now it's been categorized as a Dwarf Planet
2007-05-28 05:12:16 · answer #10 · answered by ericusa3 2 · 0⤊ 0⤋