Have you heard the news??

Question

Now there are 12 planets in the solar system...what are your thoughts on this?

Answer 1

It's not confirmed. But below you'll find a cnn.com story about potentially expanding the definition of the word "planet" to include a group of objects called "Plutons."

A pluton would be any celestial object with enough gravity to force itself into a round shape and that would take more than 200 earth years to make a complete orbit around the sun. Among other things, Charon (until now called Pluto's moon) would be defined as a planet in a binary system with Pluto. Pluto and Charon actually rotate around a point that is not in Pluto's center - they sort of spin around each other.

The three new planets would be Ceres, a rocky body in the Mars-Jupiter asteroid belt that was discovered in 1801 (129 years before Pluto was discovered), Pluto's moon Charon, and Xena, a new rocky body in the Kuiper belt discovered in 2003.

Answer 2

The IAU is asking for trouble on this one. They are going to have more planets than they can deal with.

The new definition is that gravity is powerful enough to make it a sphere, that it circle around a sun, and that it not circle around a point that is within some other body. According to this, Charon is a planet since the center of gravity of that system is outside Pluto, and since it is a sphere; Xena is a planet since it is a sphere and orbits the sun; Ceres is a planet for the same reasons, and so is Pluto. The Earth's Moon is not a planet according to this definition, since the center of gravity is within the Earth, and neither are Triton, Titan, Ganymede and the like.

But what about the Easter Bunny, Santa, Quaoar, Orcus, 2002 UX25, Ixion, Varuna, Sedna, and probably many more yet to be discovered? These are spheres. They orbit the Sun. So according to the new definition, all of these would be planets. Children in schools would have to learn 19 or more planets. They have trouble even remembering Mercury, Venus, Mars, Jupiter and Saturn.

I say keep it simple. There is a sharp break in the rankings at several places in the Solar System: between the Sun and Jupiter; Saturn and Neptune; Uranus and Earth; and Mercury and Xena (2003 UB 313). I think the Mercury-Xena gap should be used to define planet. This means there are eight planets.

The IAU will find out when it has a score of planets on its hands.

Answer 3

Ceres was considered a planet in the 19th century but lost the title in the early 20th. Seems they'll give it back.
Now Charon and the newest planet, designated 2003 UB313 (that is supposed to be given the unfortunate name of Xena, not to mention it's only satellite will be named Gabrielle, ugh.) join the leage of planets.
But if the same criteria that allows Ceres to become a planet, then our solar system should grow to 24 members.
I for one would like to see Ceres dropped from the planetary rolls altogether. It's just a big rock like many other KBO (Kuipper Belt Objects).

Answer 4

By Robert Roy Britt
Senior science writer
Updated: 1 hour, 29 minutes ago

The tally of planets in our solar system would jump instantly to a dozen under a highly controversial new definition proposed by the International Astronomical Union.

Eventually, there would be hundreds of planets, as more round objects are found beyond Neptune.

The proposal, which sources tell Space.com is gaining broad support, tries to plug a big gap in astronomy textbooks, which have never had a formal definition for the word "planet." It addresses discoveries of Pluto-sized worlds that have in recent years pitched astronomers into heated debates over terminology.
Story continues below ↓ advertisement

* The asteroid Ceres, which is round, would be recast as a dwarf planet in the new scheme.
* Pluto would remain a planet, and its moon Charon would be reclassified as a planet. Both would be called "plutons," however, to distinguish them from the eight "classical" planets.
* A far-out Pluto-sized object known as 2003 UB313, currently nicknamed Xena, would also be called a pluton.

That would make Caltech researcher Mike Brown, who found 2003 UB313, formally the discoverer of the 12th planet. But he thinks it's a lousy idea.

"It's flattering to be considered discoverer of the 12th planet," Brown said in a telephone interview. He applauded the committee's efforts but said the overall proposal is "a complete mess." By his count, the definition means there are already 53 known planets in our solar system, with countless more to be discovered.

Brown and another expert said the proposal, being put forth Wednesday at the IAU General Assembly meeting in Prague, is not logical. For example, Brown said, it does not make sense to consider Ceres and Charon planets and not call our moon (which is bigger than
both) a planet.

IAU members will vote on the proposal on Aug. 24. Its fate is far from clear.



***Not quite sure, yet what my thoughts are...will be interesting to see what happens, though.

Answer 5

It is not official yet (unless you heard something in the past hour, but the IAU is debateing planetary definitions right now and may in fact raise the number to 12 (adding Charon which is currently Pluto's moon, Ceres, which is the largest asteroid, and Xena, a mass beyond Pluto's orbit by many millions of miles). In fact, I had heard about Xena several years ago and taught my science classes about it, but at the time the name being used was Sedna, an Inuit goddess of the someplace cold (underworld, whatever). They may also give the axe to Pluto and raise the bar for planethood so it no longer qualifies.

I'm all for it, as long as they agree and can come to a working definition of what makes something a planet in terms of size, orbital mechanics, and compostion.

Answer 6

It sounds like a reasonable compromise to me. Any object which is big enough to become spherical from its own gravity (and orbits a star) will be a planet. Pluto qualifies, as does 2003 UB313 (Xena), but so does Ceres (also an asteroid). We will find that some objects are both asteroids and planets (like Ceres) and some are both plutons and planets (like Pluto, Charon, and Xena), but most of the huns of ice out there are simply not big enough to qualify as a planet.

Answer 7

I don't think there are twelve planets in the solar system. Cause if there were it would be all over the news and whoever discovered the rest of them would be rich.

Answer 8

I saw that on MSN earlier, I think they should do it, the solar system would not be correct if we didn't add the other planets. I just want to know why they chose the name Ceres, Charon and Xena. If we dn't do it now, it will be done later down the line.

Answer 9

No big deal. We've alwayse known there's a lot of crap floating around out there past Neptune. We still don't really know what constitutes a planet.

Answer 10

I think it says good things about the state of astronomy in the late 20th/early 21st centuries. Although I fear for the school children who will have to come up with a new mnemonic device.