Our Moon Could Become a Planet 438
anthemaniac writes "Earth's moon is drifting away from us more than an inch every year. In a few billion years, if the system survives, the moon would be reclassified as a planet under the new IAU definition. You gotta wonder if the astronomers who dreamed this definition up had thought of that."
Because *somebody* has to say it... (Score:5, Funny)
That's no moon!
Re:Because *somebody* has to say it... (Score:5, Funny)
What would its name be (Score:2)
Ceti Alpha 6?
Maybe it should get a real name anyway, instead of just a descriptive. Praxis I'm thinking, or Zoidberg maybe.
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Or Lord Erstwhile HengleBinker III.
Or Uranus. So people can shout "Look, I can see your...." Oh wait. Somebody did that already...
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Re:What would its name be (Score:4, Funny)
And "moon" was only the name of our moon (Score:3, Funny)
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THIS IS CETI ALPHA FIVE!!!
</Obligatory-Quote>
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No, really [mutineersmoon.com]. (Ignore the SQL error, click the art galleries.)
Basketball is a peaceful planet! (Score:4, Funny)
Neither planet nor moon in identity
The IAU bickered
It was too close to Earth; no Pluton, pity.
In a few billion years... (Score:5, Informative)
Re:In a few billion years... (Score:5, Funny)
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Re:In a few billion years... (Score:5, Informative)
Re:In a few billion years... (Score:5, Funny)
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'kin hot and 'kin huge... how about most of the sky??? it expands out to 99% of 1 AU and we move out to 1.7 AU...
I'm not sure about some of the young whippersnappers in here... but I, for one, certainly don't expect to be around to find out...
Re:In a few billion years... (Score:4, Informative)
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Do the math... (Score:3, Funny)
It will happen in a few million years, not billion. Google the math:
distance of barycenter from center of Earth: 2,900 miles
radius of Earth: 3,960 miles
distance of barycenter from Earth's surface: 1,060 miles
same, expressed in inches: 67,161,600 inches
speed of lunar creep away from Earth: 1.6 inches / year
Time until the barycenter is on the surface: 41,976,000 years.
That is pretty dang short in the context of astronomy. Or even in the context of geology. I think it would be truly short-sighted (I
Re:Do the math... (Score:5, Informative)
The Centre of mass is right in the centre of the space between them.
The distance X increases by 1 unit, does the centre of mass also increase by 1 unit?
Adjust this equation to put it into earth/lunar context and you will understand why scientists don't just "google the math".
It'll last our time (Score:5, Informative)
Got enough time to change the definition (Score:5, Funny)
The problem will fix itself in time I guess.
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And now I'm going to liberally whip you with my soggy sheet...
Hmm (Score:4, Insightful)
Re:Hmm (Score:5, Insightful)
A billion years? If our descendents exist by that time, they won't be considered human by our current definitions. I think it's a safe bet that the only way humans as we know them today could survive that long would be by either time-traveling or becoming a part of some aliens' (or dolphins') "Save the Humans" project.
It's not a moon... (Score:5, Funny)
Reminds me of that old joke telling that a quick computation on the evolution of this distance placed the moon 4 meters away from the earth 65 million years ago and thus explained why the dinausors died.
This is going to complicate things. (Score:4, Funny)
Seriously though, the International Astronomical Union better give this a second thought. I may be woefully ignornant on the subjecct but I really don't see why sticking with the current definition is a problem. I wish the article gave more information as to why they're 'fixing' that which doesn't appear broken.
Re:This is going to complicate things. (Score:5, Insightful)
Could you tell me what the 'current' definition is?
The problem was that there wasn't a definition before. More of just an accepted method of measurement. And it was arbitrary. I think it was generally based off of 'anything as big or bigger than pluto is a planet'. That's not scientific at all. The new definition is great. It relies on science to determine the status of 'planet' rather than something arbitrary picked out of the sky to satisfy what people had learned in grade school.
Re:This is going to complicate things. (Score:4, Insightful)
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The problem is that any consistent, non-arbitrary definition will result in either 1) removing Pluto's planetary status, which people don't seem to like for some reason, or 2) adding a lot more "planets" to the solar system.
The new definition is (in summary) that a planet is anything that orbits primarily the sun and is large enough
Re:Sun or Earth? (Score:4, Interesting)
Re:Sun or Earth? (Score:5, Informative)
Which was a collection of essays on various interesting science stuff, though I don't know if any of it was published seperately.
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Re:This is going to complicate things. (Score:4, Funny)
Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto, and that new one.
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http://en.wikipedia.org/wiki/Egg_(biology) [wikipedia.org]
ok (Score:3, Interesting)
Pluto may oir may not be a planet, but who cares? Don't change the definition because it doesn't change anything and it alters what we have traditionally though of it as and causes confusion with no real benifit. As to the three new planets which might come about because of this I think we should treat them with scepticism, I'm not completely against change if there will be an imporvement to understanding but I feel these things are not really in the spirit of being "planets" (I know that sounds crazy but you probably know what I mean...)
Who cares? (Score:3, Insightful)
The brutal truth is that there are at least three types of bodies that orbit the sun - rocky planets, gas giants, and bodies made up primarily of ices like Pluto and his frien
Re:Who cares? (Score:4, Funny)
Many things will happen ... (Score:4, Insightful)
In a few billion years, if the system survives,
If we manage to figure out a way to move Earth away from the sun before it goes red giant, it will most likely involve leaving any unnecessary baggage (like orbiting balls of rock) behind.
Re:Many things will happen ... (Score:5, Funny)
And no electronic devices. Or Liquid.
Orbiting balls of rock won't even fit through the scanner.
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Re:Many things will happen ... (Score:5, Funny)
Re:Many things will happen ... (Score:5, Funny)
Re:Many things will happen ... (Score:4, Funny)
Re:Many things will happen ... (Score:4, Funny)
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Few Billion Years? (Score:5, Insightful)
Re:Few Billion Years? (Score:4, Interesting)
The odds of current civilization lasting another thousand years may be low, for the reasons you cite. The odds, however, of us successfully wiping out so much of the population that humans are no longer a viable species within the next thousand years are, in my opinion, fantastically low. We breed too fast, we're spread over 30% of the planet's total area, and we're highly adaptable to changing conditions.
Frankly, I fully expect some descendant species of humans to be living here pretty much right up until the planet is inside the sun.
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Wait a minute... (Score:3, Interesting)
So is this established fact now? I thought the that was far from proven, and even a quite debated theory.
But maybe the impact hypothesis has gained traction in the science community since I heard of this?
Fatal Flaw in IAU Definition (Score:3, Interesting)
The problem is that barycenter of Jupiter's orbit around the Sun is also outside the Sun. Therefore, by the same logic, Jupiter wouldn't be a planet.
Bruce
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Eh. I have a problem with that. (Score:5, Funny)
IIRC, Jupiter has only about 1% of the mass needed to achieve fusion, so it's a long, long way from being a star. I, on the other hand easily have ten times the mass required to be a super model.
Re:Eh. I have a problem with that. (Score:4, Funny)
Re:Fatal Flaw in IAU Definition (Score:4, Informative)
Taking the long view? (Score:5, Funny)
Earth's rotational inertia is limited (Score:5, Interesting)
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Good point. You must be the Vincent Cate I remember from s.s.[hp]
If Ceres is reclassified as a planet I wonder if this would make it more attractive for a manned mission. An astronaut could be the next Armstrong (first to walk on another planet orbiting the sun) for much less than the cost of landing on Mars.
That is assuming that the Moon doesn't get reclassified. If that happens Neil, Buzz and Mike have a party.
Seven years ago, to be exact (Score:4, Funny)
Remember when that radioactive waste dump on the moon blew up and sent big chunks of it all over the place? Yeah, that was some kind of fireworks. Good thing it was on our side of the planet when it happened or we'd have missed all the fun.
Too bad about that moon base that was on one of the smaller chunks. That thing really hauled ass. Oh well, so it goes.
Huh? What!? Oh, a few BILLION years. Well... (Score:2, Offtopic)
You have to wonder.. (Score:2)
If the astronomers who thought of the new classification system really give a shit about reclassifying something that will happen in a FEW BILLION YEARS.
If we are even still on Earth in the year 3,000,000,2006 - that is.
I Am Not An Astrophysicist (Score:2)
Earth won't still be rotating by then (Score:4, Insightful)
It was projected that in a matter of millions of years, the moon will cause the earth to stop rotating altogether. Without rotation, do you seriously think we will inhabit this planet?
For that matter, in a matter of millions of years, we should have developed a technology for making the earth rotate as fast as we wish, and moving the moon back where we want it to be. All it requires is enough rocket-power by even today's standards.
Planetary System rather than Planet/Moon (Score:4, Insightful)
Ditto for Pluto and Charon.
Our biggest problem then ... (Score:3, Funny)
Both a planet and a moon (Score:4, Interesting)
Not a bad situation at all (Score:5, Interesting)
Currently, the Earth's barycenter is three-fourths of the way to its surface, causing it to sort of wobble, rather than fully orbit an invisible point. This is like an analogy: This is like a Chippendale stripper doing a pelvic thrust, rather than running around in a circle.
Earth's orbit around the sun currently makes the sun wobble in a barely perceptible fashion. Jupiter's orbit around the sun, however, causes the sun to orbit a point about 7% above its surface. I think that there should be a new class of planets for the purposes of describing a planet that makes a star orbit itself in this manner.
Clearly, all brown dwarfs orbiting a star would also have a similar or greater effect. The best way to describe it, in my opinion, would be by merely affixing "co-orbital" to describe a planet altering the sun's orbit in this fashion, or a brown dwarf orbiting a star doing this.
If this causes a planet to be "co-orbital" for only part of its orbit, or a natural satellite to be a planet for part of its orbit, in some eccentric situations, that's fine with me. There's one other issue with the new definition that makes me uncertain, though. EL61 is a "minor planet" that has a very oblong shape caused by its own orbit around the sun. If it were in a slower, closer orbit, its own gravity would almost certainly be enough to warp it into a nearly spherical shape. Should EL61 be considered a planet, despite its problem?
If only Abbot & Costello were still around... (Score:3, Funny)
"I am from planet Moon."
"What?"
"@#)$*(@#($&*(, I told you LAST TIME What's on second!!!! Graaaah!"
So, how long did it take to GET there? (Score:3, Interesting)
But the moon is drifting away due to tidal effects. So it would have been drifting faster in the past. Taking that into account, the MAXIMUM possible time the Moon could have been orbiting earth is less than 1.5bn years.
So how come many scientists think the Earth-Moon system is 4.5bn years old? Maybe they just haven't done the math.
Re:So what? (Score:5, Insightful)
I would gladly send my kid to this elementary school if they could prove that they could teach concepts like orbital decay and barycenters to to nine-year-olds.
Re:So what? (Score:5, Funny)
I would only send my kid there if they LEARNED it. I have a feeling they most nine-year-olds would be picking boogers during that class.
Re:So what? (Score:5, Funny)
Re:So what? (Score:5, Insightful)
Comets, asteroids, planets, stars, they all have grey areas between them.
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Assuming you're playing the 2600 version, you might want to get your TV checked. The area between the Asteroids should be black.
Oh, and be careful with pulling down to warp. It can throw you into the darndest areas.
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Faded in the wash...
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Except "you" won't be a human anymore. There's a high probability "you" won't be what we call a mammal. Maybe not even a vertebrate.
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Unless I get reincarnated. In which case I'll be a three toed sloth. Or a dung beetle. Or... Or... So many karmic possibilities, so few incarnations!
Re:Gosh. How shocking. (Score:5, Informative)
Re:Gosh. How shocking. (Score:5, Insightful)
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Well thank God for that. My head would probably asplode if they decided Mars wasn't a planet, although the Big Ass Red Round Thing has a nice alliterative ring to it.
KFG
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The terms "moon" and "double planet" are arbitrary human-made definitions. And they have a generally recognized boundary: is the barycenter inside the larger object or not? FYI, the Earth-Moon system is 79% of the way there.
Obviously, the moderators who gave a +3 Insightful to your comment mistook your arrogant tone for expertise.
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Re:Semantics (Score:2, Interesting)
Which is fundamentally what this is about, right? (Score:3, Informative)
This can happen a lot with scientific terms; psychiatric terms come to mind - "manic" and "psychotic" have technical definitions that are only vaguely related to what the public thinks those words mean...
Re:And what's the problem? (Score:5, Insightful)
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Re:sea levels (Score:5, Informative)
It was my understanding that the moon affects the level of the tides, not the mean sea level, which is far more a product of the Earths gravity and dependant sea water pressure/density.
Yes all those scientists must have missed that one, eh?, I am glad there are informed people like you in world to set them straight.
You are assuming that all the ice is in the seas, which it is NOT. A large amount sits on land in the form of Ice Shelves, there is enough to cover an entire contient (Antarctica) as well as most of Greenland and Canada, not to mention all the ice in Glaciers. As all this melts (and there is enough in Antarctia to contain 90% of the worlds fresh water) it wil flow into the sea and the sea level will rise, that is 'the big deal'.
But don't worry I am sure Mr President will give you a big pay rise for that wonderfully dismissive comment on the effects of climate change.
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Never attribute to malice what can be adequately explained by stupidity.
Re:What, exactly, do the slashdot editors do? (Score:4, Interesting)
Maybe you should RTFA. The SPACE.com story is talking about in a few billion years, when the barycentre of the Earth-Moon system has moved above the surface of the earth. That would make the Earth and the Moon double planets. In a few billion years. The IAU FAQ you quoted was more concerned about right now.
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