Pluto is discarded as a planet in our solar system?? what will be the next step?

Question

pluto is removed frm the list of the 9 planets.It was one of my prediction.But what will be the next step of scientist to reconsider our solar system.what abt Xena,sedna,charon,ceres.????????

Answer 1

There are now three categories, "classical planets", "dwarf planets", and "small solar system bodies".

The planets Mercury through Neptune are now the classical planets. Pluto is classified as a dwarf.

The asteroids, comets, and other objects in our solar system are small solar system bodies.

The definition of a planet, as created by the IAU:

"(1) A planet is a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighbourhood around its orbit."

Since Pluto's orbit crosses Neptunes, it does not meet criteria (c).

The object nicknamed "Xena" may very well become the next ninth planet.

Charon remains a moon of Pluto- its orbit takes it around Pluto, not the sun. Ceres lost its status as a planet in 1800.

Answer 2

To facilitate discussion of this question, here is a site that describes the removal of Pluto from the list of planets.

Enjoy


The IAU members gathered at the 2006 General Assembly agreed that a "planet" is defined as a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighbourhood around its orbit.

This means that the Solar System consists of eight "planets" Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. A new distinct class of objects called "dwarf planets" was also decided. It was agreed that "planets" and "dwarf planets" are two distinct classes of objects. The first members of the "dwarf planet" category are Ceres, Pluto and 2003 UB313 (temporary name). More "dwarf planets" are expected to be announced by the IAU in the coming months and years. Currently a dozen candidate "dwarf planets" are listed on IAU's "dwarf planet" watchlist, which keeps changing as new objects are found and the physics of the existing candidates becomes better known.

The "dwarf planet" Pluto is recognised as an important proto-type of a new class of trans-Neptunian objects. The IAU will set up a process to name these objects.

Answer 3

Let's face it, if the did not "demote" Pluto, that opened the door for pretty much anything that's round to be called a planet, regardless of size. Pluto fits the accepted definition of a Kuiper Belt Object much better than it fits the definition of planet. If it remained a planet, there were potentially dozens of KBO's that would have to be designated planets as well. All those other objects you named would have been just the first of many, many new "planets." It makes sense. Even when Pluto was discovered in 1930 debate raged over whether to classify it as a planet, due to it's size and elliptical, off-kilter orbit and that was long before astronomers even knew the Kuiper Belt (with all its Pluto-like objects) existed.

Answer 4

Does it really matter what we label these things? Just because we slap a label on them doesn't matter: they're still there, we recognize that they exist...it's not like we blew up Pluto...we just re-labeled it to satisfy our human need classify and label - as if that will give us a better understanding of things. Unfortunately, it doesn't really do that. Outer space remains as it was and there's nothing we can do here on earth about that. Classification obviously does serve a purpose and it does keep things cleanly organized - I'm just going off on a tangent b/c people are freaking out over this!

Answer 5

All giant balls of gas shall be removed. Too bad though. I think anything solid that's big enough and in orbit around the sun will remain.

Answer 6

I for one am thrilled that Pluto has been demoted. It used to be a moon of Neptune, and it is smaller than many other moons in our system.

Answer 7

they'll form the group of "drawf planets" along with some other small heavenly bodies like asteroids,comets etc..

Answer 8

mercury is next.

Answer 9

It was? Why?

Answer 10

it is not discarded?????????!!!!!!!!!!!!!!!!11