how is it possible for pluto to now not be a planet and for 3 more to come along out of the blue!?

Question

(or out of the black should I say)

what are the three new planets and how big are they compared to earth or mars and where are the located exactly. and why the hell has nobody heard of them! And why weren't they classed as planets before! ????????????????????????????

Is ceres the one that sits between mars and jupiter? where the asteroid belt is? To be a planet the body must be round like earth, so is ceres round?

Answer 1

They're all kuiper belt objects. Basically a big cloud of planetoid stuff hanging out around the edge of the solar system. We classed pluto as a planet because we found it first, and didn't know there were others. Now there's a debate as to whether Pluto is actually a planet since we know that there's lots of these out there (and if pluto is a planet, the ones that are larger than pluto would have to be considered planets too)

Pluto is 2274 km across.

Answer 2

Pluto actually hasn't been removed from the planetary list quite yet, and I doubt it ever will just for historical sake. In the scientific community there is a debate raging on how to define a planet. In the case of Pluto, people are saying it is actually a comet since if it was in the same orbit as earth, it would grow a tail. Also there is the issue of its size. For example the moons of Jupiter are bigger and actually have more "planet" like properties than Pluto but are considered moons. Our moon also falls into that category.

The new planets you are speaking of, the "planet X's", are more asteroid like than they are planets, but they do orbit our sun in a plane similar to the standard planets, so some consider them planets, and that is where the debate is coming in. Some years ago they came up with the classifications of Major Planets and Minor Planets to help discern between all these planetary bodies. Major planets are the ones you generally think of when you think of the planets (earth, Venus, Jupiter, Saturn, etc). Minor planets are those like the newly discovered planets and possibly Pluto if it reclassified as such.

I suppose to summarize, there is no clear definition of what a "planet" is. Some say if it orbits the sun and is a decent size, its a planet, but that gets fuzzy when there are some big asteroids. There is actually a really good special on the Science Channel about Pluto and this debate that is very interesting. Look it up and take a look.

Answer 3

This is all exciting and strange. It will be decided soon by the International Astronomical Union. The new list of planets in the solar system will be Mercury, Venus, Earth, Mars, Ceres, Jupiter, Saturn, Uranus, Neptune, Pluto, Charon, and 2003 UB313. Ceres in the largest asteroid. There is a new class of planets called "plutons", or pluto-like objects. That is what Pluto, Charon and 2003 UB313 are. Plutons differ from classic planets in that they have orbits around the Sun that take longer than 200 years to do, and their orbits are tilted and non-circular.

Answer 4

It's possible because astronomers are debating it right now. The predicted outcome of the debate, however, is that pluto will remain a planet. Charon will become a planet rather than a moon because pluto and charon rotate around each other (rather than charon orbiting pluto) and they both take the same orbit round the sun together. Ceres is in the asteroid belt and has sufficient mass to make it a spherical shape. 2003 UB313 sits in the Kuiper belt (Xeros) and will be given planet status because it also has sufficient mass to have a spherical shape. So say the boffins anyway.

Answer 5

Pluto has been considered a planet for a very long time. There was a brief period when it wasn't. It is 1430 miles in diameter. For reference, the Earth is 7926 miles in diameter and Mars is about 4200 miles in diameter

Charon, considered to be Pluto's Moon is one of the three new planets. It is about 750 miles in diameter. Technically it is not a moon of Pluto, because it does not orbit Pluto. Both Pluto and Charon orbit a common point that is outside either mass. In other words they are a binary planet system. Kind of neat, huh?

Ceres is in the asteroid belt. It is round and measures 578 miles in diameter.

2003 UB313 , also sometimes known as Xena, is about 1400 miles in diameter.

These objects have been known to exist, or are relatively recently discovered, but the key is that the International Astronomical Union is just getting around to defining what a planet is.

Answer 6

I have heard of the 3 new planets, but I don't know their names (or have they been given names at all). Those planets have been discovered to orbit around the Sun just recently. They are even further away then Pluto, which we considered so far the last planet of the Sun sistem. Probably the reason why they havent been classed as planets is that they haven't been spotted. Until now.
Pluto cannot be taken as a planet for several reasons - it's orbit is highly irregular, so that it happens that it is closer to the Sun than Neptune, the eight planet! There's another thing about it - Pluto has a natural satelite, about the same size as the 'planet', but it doesn't revolve around it. Both bodies revolve around a imaginative spot right between them. It looks more like two asteroids then a planet and its moon.

Answer 7

The three others being considered are 2003 UB313, Charon (Pluto's largest moon) and Ceres (asteroid). People have heard of them - lots of people - just not you or most of the general public that doesn't follow astronomy news. Pluto may or may not be classified as a planet because astronomers and physicists don't have a clear definition of what a "planet" actually is. So, when they come up with a definition, Pluto may or may not fit in.
There is a good explanatory article up on CNN.com right now - link below.

Answer 8

They decided to do this? That's terrible.

IMHO, they should have dumped Pluto.

I would have dumped the term "planet" altogether because it means nothing.

Mercury, Venus Earth and MArs are "terrestrials."

Jupiter, Saturn, Uranus and Neptune are "Jovians" or gas giants. Pluto is a Kuiper Belt Object or KBO.

In order to be a terrestrial, you'd have to have a solid surface, orbit the sun (not another terrestrial or jovian), and have enough mass so that gravitational forces renders it near spherical.

By making Ceres and Charon planets, they's have to make the Moon a planet and a few of Jupiter's moons too!

Answer 9

Pluto *is* still (sort of) a planet but in a class called pleurons, the International Astronomy Union have voted to keep it, despite it being smaller than our own moon. We have fanother three pluerons, Pluto's moon Charon, an asteroid that sits between Mars and Jupiter called Ceres, and an object officially called 2003 UB313 but nicknamed Xena.

The equatorial diameter of the objects are (in miles): Pluto, 1,432.9, Charon, 749.9, Ceres 579.7 and "Xena" 1,491.3. (the furthest out, 9 bn miles from the sun.) To compare Earth has a diameter of 7,926.4 miles.

The reason we see them now is the advance in our technology.

Answer 10

The scientific scholars are pondering this question at the moment...But here and now Pluto is the only planet discovered(supposedly) by an American, with the dislike of Americans right now poor Pluto is taking a hit
Truth is Pluto is a planet always has been so to hell with the rewriters of history.. Too much of history is being rewritten to salve the turbulant souls that don't like something in history that spoke of heritage of non americans ... what a shame, and shame on us all for letting it happen..............