Why did Pluto lose its status as a planet?

Question

Since when was Ceres even a planet? i never heard of it until now... and all those other little planets. Whats up with this crap a dot is considered a planet now back in the day we had 9.

Answer 1

The International Astronomical Union decided that Pluto was no longer a planet. The reason is that while Pluto is round, orbits the sun, and has three moons, it has not cleared (via gravity) its own orbit of debris. Instead, they decided to classify it as a "dwarf planet".

See the details below.

RESOLUTION 5A
The IAU therefore resolves that "planets" and other bodies in our Solar System, except satellites, be defined into three distinct categories in the following way:

(1) A "planet" [footnote 1] 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.

(2) A "dwarf 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 [footnote 2] , (c) has not cleared the neighbourhood around its orbit, and (d) is not a satellite.

(3) All other objects [footnote 3] except satellites orbiting the Sun shall be referred to collectively as "Small Solar-System Bodies".


Footnote 1: The eight "planets" are: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.

Footnote 2: An IAU process will be established to assign borderline objects into either dwarf planet and other categories.

Footnote 3: These currently include most of the Solar System asteroids, most Trans-Neptunian Objects (TNOs), comets, and other small bodies.

RESOLUTION 6A
The IAU further resolves:

Pluto is a "dwarf planet" by the above definition and is recognized as the prototype of a new category of trans-Neptunian objects.

Answer 2

It must be in orbit around a star without being a star itself. It must contain sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium nearly round shape.It must have cleared the neighbourhood of other celestial objects and dominate its orbit. In other words it should not share its orbital region with other bodies of significant size save for its own natural satellites and other celestial objects under the influence of the gravitational forces exerted by it. As a result of these definitions on August 26, Pluto was stripped of its status as a planet This was partly due to how Pluto’s mass did not exceed that of several moons of the other eight planets, but mainly because Pluto followed a Trans-Neptunian orbit, meaning during part of its orbit it is at a closer distance from the Sun than Neptune, hence breaching the third definition. So Pluto has joined Eris and its own moon Charon under the category ‘dwarf

Answer 3

Yes. It was demoted to a Dwarf Planet.

The Kuiper belt is believed to be the source for all short-period comets, and Pluto, like other Kuiper Belt objects, shares features in common with comets. The solar wind is gradually blowing Pluto's surface into space, in the manner of a comet. If Pluto were placed near the Sun, it would develop a tail, like comets do.

Among the objects of the Solar System, Pluto is not only smaller and much less massive than any planet, but at less than 0.2 lunar masses it is also smaller and less massive than seven of the moons: Ganymede, Titan, Callisto, the Moon, Europa and Triton. Pluto is more than twice the diameter and a dozen times the mass of Ceres, a dwarf planet in the asteroid belt. However, it is smaller than trans-Neptunian Kuiper belt object Eris, discovered in 2005.

http://en.wikipedia.org/wiki/Pluto

Answer 4

Pluto is a tiny ball of ice that shares its orbit with billions of other objects just like it. If Pluto is a planet, then all the asteroids and comets and everything else is a planet, too. The reason Pluto is not called a planet anymore is simply because we needed to differentiate between various objects in our solar system.

Ceres was called a planet when it was first discovered. After a few years, people realized that it was only the largest of millions of asteroids in the same orbit.

Answer 5

Pluto didn't change.

The standards that define what a planet is have changed. It's no big deal. One hundred years ago, people didn't even know Pluto existed. Heck, 20 years ago, YOU didn't exist!

I wasn't that long before that we thought there were only five planets, and not long before that we thought all those lights in the sky were stars.

Heck, just over a thousand years ago, most people on earth thought those were little rips in the curtain that coverd the sky at night.

The universe changes as we learn new things so we have to keep changing our perceptions or get left behind in the dark ages.

Answer 6

The existence of Pluto as a planet was debated by the worlds top scientists. They concluded that it was a Dwarf, not a planet. Now we have 8 planets in or solar system.

Answer 7

pluto was accidently considered a planet, first of all there are bigger moons than pluto in our solar system.ceres is a planet but isnt very popular. you must have thought it was not even around because it is even more far away from the sun than pluto. they must have not talked about it because science to look farther than pluto must have not been around bACK in the days. this dot is bigger than pluto . that is way the science commision does not call pluto a planet anymore!

Answer 8

Check out the story at the wiki site.

Ceres (and a few others) were planets at the beginning of the 19th century (1801 and following). They were demoted to "minor planets" when the nature of the gravel pit between Mars and Jupiter became better understood.

The same is becoming true of the ice mine between Neptune and the Oort cloud.

Answer 9

According to the tabloids, wild party planet Pluto lost his Planetary status after multiple accounts of

*Orbiting under the influence (of other space objects)
*Eratic Orbiting (Pluto's lawyer refuses to disscus the results of any sobriety test)
*Orbiting while undersized
*Hanging out at Hollywood's Chateau Marmont with his astroid buddies, trashing the place, snorting interstellar dust and not paying the bill.
;)

Answer 10

Pluto, the final planet to connect the heavenly pantheon, grew to grow to be the 1st to go away it. The status of Pluto were under dialogue for some time, yet with the invention of 2003 UB313, nicknamed Xena, the question grew to grow to be acute, for it probably had as lots acceptable as Pluto to be stated as a planet. On August 24, 2006, the international Astronomical Union greatly surprised the international by utilising vote casting in a sparkling definition of planet, one that could desire to exclude Pluto and produce the completed variety all the way down to eight. (There had till now been been stable hypothesis that the redefinition might deliver the completed as much as twelve fairly of down.) Pluto grow to be fairly categorised as a dwarf planet, alongside with Ceres and the aforementioned Xena. the key distinction between a dwarf planet and the actual element is that the dwarf variety has no longer cleared the portion of its orbital direction. This redefinition met with a wave of protests from people who wanted to work out the 9th planet grandfathered in, which consists of yet no longer constrained to supporters of the previous due Clyde Tombaugh, who stumbled on Pluto in 1930. His widow, besides the undeniable fact that, stated he could have been accepting of the IAU's decision provided that "he grow to be a scientist" and understood that astronomers had to contemplate newly stumbled on gadgets interior the Kuiper Belt (the place Pluto is placed). yet fighters of Pluto's demotion proceed to be unconsoled and have generated a thriving industry in T-shirts, mugs and different memorabilia. considered one of numerous slogans of this pass grow to be one that performed on the mnemonic for the names of the erstwhile 9: