Dynaverse.net
Off Topic => Engineering => Topic started by: The Postman on August 16, 2006, 07:38:03 am
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THE MEANING OF PLANET: What is a planet? For years, astronomers have been debating that question, with the status of tiny Pluto hanging in the balance. Finally, an answer is in the offing. The International Astronomical Union's Planet Definition Committee has proposed a new, official definition:
"A planet is a celestial body that (a) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (b) is in orbit around a star, and is neither a star nor a satellite of a planet."
In plain language, if it's round and it orbits the Sun, then it's a planet.
On August 24th, astronomers gathered at the IAU General Assembly in Prague will vote on the proposal, yea or nay. If it passes, the Solar System will have twelve planets: Mercury, Venus, Earth, Mars, Ceres, Jupiter, Saturn, Uranus, Neptune, Pluto and Charon (a double planet) and 2003 UB313.
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o fun, guess i'll have to learn a new diddy ;)
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2003 UB313 don't exactly roll off the tounghe, and 'Xena and it's moon Gabrelle' is just a little to corny to work out.
I hope that they give it a REAL name soon.
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Keeping with the theme of the others, I'd suggest
Cania - An area of the frozen lake Cocytus, in Dante's 9th circle of hell. Certainly a frozen hell would be an apt description.
Tartarus - Both a Greek God and a place farther even than Hades, where the cosmos originated.
and Skiron, one of the Winds who chose the air for her earthly body.
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I honestly find this topic very interesting, but I have to ask.
Does anyone else find it ridiculous that a random group of people that I've/we've never heard of are given the authority or take the authority upon themselves to dictate what does or does not constitute a planet? Also that they then decide how many planets our solar system has? "Do I hear 10...12...15 anyone?...16 from the man in the back."
My suggestion for a planet --> Must revolve around a star not another planet (unless some kind of twin planet) and must have an atmosphere. That covers Pluto doesn't it? If not then grandfather it in and dump the rest. The other eight have atmospheres right, even if very thin ones?
Big giant ice covered round rock without atmosphere <---not a planet
I really don't care who decides what, I can remember nine and MVEMJSUNP and I refuse to learn anymore or drop any of the nine. :-\
Keep in mind I'm not an astronomer and don't pretend to be.
Oh and be sure to post what they decide
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I'm not sure Mercury has an atmosphere.
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Mercury is much too small for its gravity to retain any significant atmosphere over long periods of time, but it does have a very tenuous atmosphere containing hydrogen, helium, oxygen, sodium, calcium and potassium. The atmosphere is not stable—atoms are continuously lost and replenished, from a variety of sources. The hydrogen and helium atoms probably come from the solar wind, diffusing into Mercury's magnetosphere before later escaping back into space. Radioactive decay of elements within Mercury's crust is another source of helium, as well as sodium and potassium. Water vapor is probably also present, water being brought to Mercury by comets impacting on its surface.
Close enough for me
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What happened to Sedna? Isn't Sedna a planet also?
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(a) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (b) is in orbit around a star
Hmmm.....
Some people I know now qualify as a planet.
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1/ Spherical (approximately - allowing for tidal and rotational forces)
2/ Solid core consisting of rock and or metal.
3/ Remained molten long enough to have denser materials sink to the core.
I suspect that this would disallow Pluto, all asteroids and the objects so far discoverd beyond pluto while allowing the other 8 planets to remain classified that way. It would also reclassify the Earths moon as a planet. Other large moons might also so qualify.
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i don't care what they do, as long as pluto is grandfathered either way ;) we must have no less then 9 planets ;)
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If they discover a tenth or and an eleventh planet, can I sue my astrologer?
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A proposal on a method to limit the number of new planets in the solar system (http://ars.userfriendly.org/cartoons/?id=20060820)
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Bah!
Pluto is a planet because we say its a planet . The very concept of "planet" is an arbitrary human invention , not a law of physics or mathmatics.
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Bah!
Pluto is a planet because we say its a planet . The very concept of "planet" is an arbitrary human invention , not a law of physics or mathmatics.
The very concept of 'numerical worth' was also a human invention.
After all, what 'one' is the value of 'one' based on?
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Bah!
Pluto is a planet because we say its a planet . The very concept of "planet" is an arbitrary human invention , not a law of physics or mathmatics.
The very concept of 'numerical worth' was also a human invention.
After all, what 'one' is the value of 'one' based on?
Its precisly half the value of two . ;D
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but then if you have .01 of something and not the rest of it, cannot the .01 be redefined as 1?
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Bah!
Pluto is a planet because we say its a planet . The very concept of "planet" is an arbitrary human invention , not a law of physics or mathmatics.
The very concept of 'numerical worth' was also a human invention.
After all, what 'one' is the value of 'one' based on?
Your IQ?
=) hehe
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Bah!
Pluto is a planet because we say its a planet . The very concept of "planet" is an arbitrary human invention , not a law of physics or mathmatics.
The very concept of 'numerical worth' was also a human invention.
After all, what 'one' is the value of 'one' based on?
Your IQ?
=) hehe
You are setting the value of '1' very high, indeed, grasshopper.
But you perfectly illustrate my point. If the concept of '1' indicates '1' grain of sand, it represnts little, but if it represents '1' SPECIES, it can represnet a lot.
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Eh, since the word "Planet" is a human distinction and an admittidley arbitrary definition, I don't have a problem with us declaring one ball of rock a planet and another ball of ice, not.
The people/creatures who live there will experiance the real estate boom or crash depending on the naming of their particular ball of rock/ice a planet or asteroid will just have to deal with it.
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http://dsc.discovery.com/news/2006/08/23/newplanet_spa.html?dcitc=w01-101-ae-0000
New Planet Rules Divide Astronomers
William J. Kole, Associated Press
Aug. 23, 2006 — Leading astronomers are bitterly divided over new galactic guidelines that for the first time would define what is and isn't a planet, all but dooming a proposal to expand the solar system to 12 planets from the traditional nine.
Caught yet again in the crossfire is puny Pluto, scorned by many as a poser that could be demoted Thursday as a dwarf — slightly shrinking Earth's neighborhood instead.
Opponents "smell blood, and I think they're going to get it," Alan Boss, an astrophysicist at the Carnegie Institution in Washington, D.C., said on the eve of a vote by members of the International Astronomical Union.
Leaders of the group, the official arbiter of heavenly bodies, caused a sensation last week by proposing that Pluto's largest moon and two other objects officially be designated as planets. They suggested that Pluto and the three newcomers be the first of a new class of planet dubbed "plutons."
The rationale was their initial draft definition of a planet: any object larger than 500 miles in diameter that orbits the sun, has a mass roughly one-12,000th that of Earth and has enough self-gravity to pull itself into a round shape.
But for many of the 2,500 astronomers from 75 countries meeting in Prague, the universe hasn't been the same since.
After days of spirited and sometimes combative debate, renegade scientists have won some key concessions.
A planet, they insist, must be the dominant object in its area. That would draw a sharp distinction between the eight "classical planets" — Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune — and Pluto, which would be known as a "dwarf planet."
Its largest moon, Charon; the asteroid Ceres, which was a planet in the 1800s before it got demoted; and a recently discovered object known as 2003 UB313 and nicknamed Xena; also would be dwarfs.
Though the precise wording of the definition remained a work in progress Wednesday, if astronomers agree that a planet must have "orbital dominance" in its own neighborhood, the new guidelines would eliminate Pluto and the trio of tentative candidates as proper planets.
"It's a kind of compromise: There would be only eight planets, plus the dwarf planets," said Japanese astronomer Junichi Watanabe, a member of the IAU's planet definition committee.
Many believe there's simply no scientific justification to grant planet status to most of the objects floating in the vast sea of rocks that reside in the Kuiper Belt — a mysterious, disc-shaped zone beyond Neptune containing thousands of asteroids and comets.
"It's impossible to draw the line between the new dwarf planets and large asteroids," said Mark Bailey, director of Britain's Armagh Observatory.
And forget the term "pluton" — it's already history.
Under pressure from a growing faction of astronomers, the planet definers have been tossing around other options: plutoids, plutonids, plutonoids, plutians, or Tombaugh objects or planets in honor of Clyde Tombaugh, the American who discovered Pluto in 1930.
Among the scientists who torpedoed "pluton" were geologists, who pointed out — somewhat embarrassingly to astronomers — that it's already a prominent term in volcano science for deep igneous rock formations.
"What were they thinking? The reaction in the geologic community was rolling of eyes," said Allen F. Glazner, a geologist at the University of North Carolina. "It would be like botanists trying to distinguish between trees and shrubs and coming up with the term 'animal.'"
Harvard's Owen Gingerich, who chairs the planet definition panel, conceded: "We perhaps stumbled."
After the panel got dozens of objecting e-mails, "we backed off," he added.
Suddenly, the future looks dim for much-maligned Pluto, which is smaller than Earth's moon.
Its underdog status has inspired scores of tributes, including one by folk singer Christine Lavin that laments: "I guess if Pluto showed up at a planet convention, the bouncer at the door might have to ban it."
"Some say, 'No, Pluto is a nice planet'" and should remain one, Watanabe said.
"It's an important object that has played an important role," he said. "But this is a natural way to draw a line."
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(a) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (b) is in orbit around a star
Hmmm.....
Some people I know now qualify as a planet.
:rofl:
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http://news.yahoo.com/fc/science/astronomy_and_space
Here goes the BS parade. Pluto is no longer a planet? :P
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Funny thing is they started out thinking they wanted to add more planets.
Now we are going in reverse.
So what are they going to call Pluto?
I don't think the Scientific community is a all in a healthy mode. We see how politics has infiltrated the system over the syears with psuedo-science like "environmentalism".
Now confusion over what makes a planet.
As I recall pluto was actually "predicted" before it was discovered based on a study of orbial permutation concerning Neptune.
I posted this on theHot and Spicey forum and got jokes. But there seems to be a more serious discussion here.
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If anything, we should have renamed Uranus.
There ya go, that's the joke on the matter. ;D Yes, this one is more serious, it also teaches ya rumrunners to go hang out in 10 forward sometimes! ;D
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I read that Pluto was automatically booted as a planet because its orbit crosses Neptune's, is that right? wouldn't that also apply to Neptune as well and boot it as a planet? Man I must be really dumb because this whole situation just gets more and more confusing for me
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I read that Pluto was automatically booted as a planet because its orbit crosses Neptune's, is that right? wouldn't that also apply to Neptune as well and boot it as a planet? Man I must be really dumb because this whole situation just gets more and more confusing for me
What is confusing to me is why are all these people spending all this time over so trivial of a topic. Don't they have more important things to do?
Wait just a minute. I guess if they weren't doing this then they'd have to actually go to work. How stupid of me to even suggest this. Sorry.
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If Pluto orbits the sun (which it does) and is not part of an asteroid belt (which it's not) then it's a planet. Perhaps they could come up with a different term to identify much smaller bodies that orbit stars. Like planetoid.
After all, Pluto is made up of solid matter where the gas giants are not.
I think these Poindexters just like to bicker.
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They are calling it a "Dwarf planet." WTF? The only dwarfs I know is "Red dwarf" and "Snow White does the seven dwarfs."
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PLUTO DECLARED A DWARF PLANET: Today at the International Astronomical Union (IAU) General Assembly in Prague, astronomers decided that the Solar System has eight planets, and Pluto is not one of them. Instead, Pluto is a "dwarf planet."
To be a planet, the assembly ruled, a world must meet three criteria:
(1) It must have enough mass and gravity to gather itself into a ball.
(2) It must orbit the sun.
(3) It must reign supreme in its own orbit, having "cleared the neighborhood" of other competing bodies.
So, e.g., mighty Jupiter, which circles the sun supreme in its own orbit, is a planet--no adjective required. Pluto, on the other hand, shares the outer solar system with thousands of Pluto-like objects. Because it has not "cleared its own neighborhood," it is a dwarf planet.
This decision clarifies the vocabulary of planetary astronomy while simultaneously upturning 76 years of "Pluto is a planet" pop-culture. Will non-specialists heed Pluto's demotion? That remains to be seen. Meanwhile, according to the IAU, the Solar System has eight planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune; and three dwarf planets: Ceres, Pluto and 2003 UB313.
IAU 2006 General Assembly: Result of the IAU Resolution votes
24. August 2006, Prague
The first half of the Closing Ceremony of the 2006 International Astronomical Union (IAU) General Assembly has just concluded. The results of the Resolution votes are outlined here.
It is official: The 26th General Assembly for the International Astronomical Union was an astounding success! More than 2500 astronomers participated in six Symposia, 17 Joint Discussions, seven Special Sessions and four Special Sessions. New science results were vigorously discussed, new international collaborations were initiated, plans for future facilities put forward and much more.
In addition to all the exciting astronomy discussed at the General Assembly, six IAU Resolutions were also passed at the Closing Ceremony of the General Assembly:
Resolution 1 for GA-XXVI : "Precession Theory and Definition of the Ecliptic"
Resolution 2 for GA-XXVI: "Supplement to the IAU 2000 Resolutions on reference systems"
Resolution 3 for GA-XXVI: "Re-definition of Barycentric Dynamical Time, TDB"
Resolution 4 for GA-XXVI: "Endorsement of the Washington Charter for Communicating Astronomy with the Public"
Resolution 5A: "Definition of 'planet' "
Resolution 6A: "Definition of Pluto-class objects"
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.
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Now hold on just a second there!
We have dwarf people but they're still people, right?
It's planetary discrimination I tell ya!
Dwarfs Unite!! ;)
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Now hold on just a second there!
We have dwarf people but they're still people, right?
It's planetary discrimination I tell ya!
Dwarfs Unite!! ;)
:rofl:
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i still say the should have just grandfathered the bloody thing and avoided the debat all together...
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I'm soooo glad we elected those bozos to make up our minds for us. NOT! >:(
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Will non-specialists heed Pluto's demotion?
No. And neither will some specialists.
-S'Cipio
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My current feelings on the subject (http://ars.userfriendly.org/cartoons/?id=20060827)
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(http://img.timeinc.net/time/cartoons/20060826/8.jpg)