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Our Moon Could Become a Planet
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."
That's no moon!
both the Earth and Moon will have been swallowed up by the Sun when it becomes a red giant...
Donald 'Duck' Dunn: We had a band powerful enough to turn goat piss into gasoline.
"The sun will turn in a red giant before the moon gets far enough away to be classified as a planet"
extern warranty;
main()
{
(void)warranty;
}
In a billion years propably the defintion of planet will have a few thousand updates.
The problem will fix itself in time I guess.
No-one knows if the humans will survive that long, maybe there will be no-one to rename it.
...oh well, forget it, it's still a moon.
...at least the tallest ones.
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.
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.
I know a lot of the other comments about this are just saying that our system probably won't be around or that of course it won't be a moon because it's not in orbit, but what I think is more interesting is about the definition of a planet which they seem intent on creating...
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...)
*''I can't believe it's not a hyperlink.''
If you'd bothered to RTFA, you'd find that the moon would be reclassified as a planet when the systems center of gravity no longer resides inside the Earth.
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.
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.
I really don't think humans will last another thousand years (with the way we're poluting the environment and declaring war on each other plus the rising threat of nuclear weapons) let alone another few billion years. And provided we do last that long, I'm sure the standards for classifying planets will have changed hundreds of more times by then.
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?
Beware: In C++, your friends can see your privates!
"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."
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.
If a nation expects to be ignorant and free, in a state of civilization, it expects what never was and never will be.-TJ
I already consider the moon-earth as a bi-planetary system. What's the big deal with these definitions, anyway? No matter where you draw the line, there will always be cases where there will be discussion. Like the criterium that the object has to be "nealy spherical" because of it's own gravity. Lots of planetoids are somewhere on this vague border.
Comets, asteroids, planets, stars, they all have grey areas between them.
"It's too bad that stupidity isn't painful." - Anton LaVey
Wrong, wrong, wrong! Just RTFA. The moon does not have to escape the Earth's gravitational pull in order to be re-classified as a planet. The only thing that would be necessary (according to the new definition of a planet) is that the Moon moves further away from the Earth, just enough so that the barycenter of the Earth-Moon system is above the surface of the Earth. The Moon would still orbit the Earth. Obviously, the moderators who gave a +5 Insightful to your comment have not read the article either.
Please stop giving +1 Insightfuls to people who either a) haven't read the article or b) haven't undestood it. The moon could be reclassified as a planet EVEN IF IT STILL ORBITS THE EARTH. It depends on whether the center of gravity of the pair is inside the earth or not.
Please read my Canon EOS tech blog at http://www.everyothershot.com
I'll still be a human. A dead human, but a human nonetheless...
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!
The problem is they're saying if a "moon" is orbiting a barycenter that's not inside another planet, then it's not orbiting that planet and becomes a planet itself. For this reason, they argue Charon is a planet, rather than a moon.
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
I reckon Eric.
Or Lord Erstwhile HengleBinker III.
Or Uranus. So people can shout "Look, I can see your...." Oh wait. Somebody did that already...
People are already arguing over things that may happen in a few billion years? I don't even buy green bananas!
Slashdot Burying Stories About Slashdot Media Owned
The energy to lift the Moon's orbit comes from the rotational energy of the Earth, which is limited. As the Moon gets higher the Earth rotates slower. There may not be enough energy to lift the Moon high enough to qualifty.
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.
#naabhaprzrag, #sverubfr-000, #agi-fcbafberq, negvpyr[pynff*=' negvpyr-ary-'] { qvfcynl: abar !vzcbegnag; }
To be fair, it was a reasonable interpretation of your post to think you were saying "it won't be a moon because it will escape and go FLYING INTO SPACE!!1" instead of the intended point "if it no longer fits a definition, it isn't what's defined. This is news?". 'course, the AC was more than a bit condescending about it.
This is called a Twin Planet. And no it would nolonger orbit the earth the earth, the "moon" would orbit eachother at a common point. Either way, I see no reason that once we have this designation of moon vs planet why we should be so beholden of "our" moon that we can't accept it nolonger being a moon. We shouldn't change the definition just to fit some popular idea.
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.
If this were really happening, what would you think?
Yup
Faded in the wash...
The moon does not have to escape the Earth's gravitational pull in order to be re-classified as a planet.
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
The fact that we have tendency to kill other members of our own species through hatred is a major cause for wars and national conflicts (WWII is a good example). This tendency could easily augment into a large-scale nuclear war which could leave the Earth uninhabitable for all species, killing 100% of the population.
I'm almost 26 and I'm picking boogers right now while reading these comments. (I'm serious)
Never attribute to malice what can be adequately explained by stupidity.
A few billion years? Why should they care?
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.
And over there we have the labyrinth guards. One always lies, one always tells the truth, and one stabs people who ask t
Or maybe he was using, I dunno, Latin?
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.
Obviously, people care tremendously, which is why we ended up with this half-assed bandaid of a definition - which is an attempt to use a single word to describe three wildly divergent phenomena in a way that makes scientific sense and will pass muster with every pseudoscientist who thinks they have a right to an opinion on the matter.
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 friends. Lumping them together as a single thing is stupid; excluding bodies like Titan, Ganymeade and Europa from their "club" also makes little sense - but imagine bruhaha that would happen if astronomers simply stopped talking about moons and planets and started talking about rocks, gasballs and iceballs...
Clear, Dark Skies
Ditto for Pluto and Charon.
I am hopefully looking forward to this "Golden Age" in just a few billions of years, when our biggest problem definitely will be the fact, that the moon would be reclassified as a planet under the new IAU definition. ;-)
Greetings,
Chris
"An operating system must operate."
Calling Jupiter a "failed star" is like calling me a "failed super model" - I mean, yeah, there's some similarities between me and a super model but it's extremely unlikely anyone would ever mistake me for one.
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.
Clear, Dark Skies
Semantics, I mean. The IAU is attempting to maintain a logically consistent definition for a technical term of art which, unfortunately has an overlapping but divergent meaning in the public's mind.
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...
Clear, Dark Skies
If what?
Oh, say does that Star-Spangled Banner entwine / The myrtle of Venus with Bacchus's vine?
We'll be a Type III Civilization and we will be able to push the moon back into orbit.
What was your username again? -BOFH
Why can't something be both a planet and a moon? As far as I understand it, the new IAU definition of a planet is something that's in orbit around a star, is not a star, and is large enough for gravity to make it roughly spherical. A moon is something that's in orbit around a planet. So you could argue that our Moon is already a planet (it's in orbit around the Sun as well as the Earth). The same would apply to many other large moons in the solar system.
Till Galileo made it a generic term. Pity no one thought to maintain the trademark.
Clear, Dark Skies
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.
SYS 64738
Wrong, wrong, wrong! Just RTFPP. The moon does not have to completely escape the Earth's gravitational pull in order for Porkchop's comment to apply.
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.
I think Asimov said something like this in one of his thousand books. His argument was that, unique among (known) moons, Luna's orbit is always curved towards the sun, making it more of a coplanet than a proper moon. But I can't remember which book it was, unfortunately.
--
I don't want to rule the world... I just want to be in charge of mayonnaise.
If the moon going further away from the Earth causes the barycenter of Earth to drift outside its surface, then the Earth will be orbiting a point outside itself, with its orbit becoming greater the farther the barycenter drifts, until it peaks at one point. This is similar to Pluto constantly orbiting a point outside itself, as illustrated in this NASA chart hosted by Wikipedia. I think that when a moon begins to have that effect, it should be classified as a planet.
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?
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 use that word deliberately) for astronomers to decide that the Earth and Moon are not a binary planet today but will become one next week (in astronomical time).
The Earth and Moon are a binary planet, have been so for a long time, and will continue to be for quite a while. It would be good if astronomers gave up their traditional notions about this and publicly recognized the truth, because only until then will the geologists and evolutionary biologists begin to take the Moon's influence into account in their own areas.
"5. The IAU classifies objects based on their current properties. Specialists note that the Moon is receding from the Earth, and in a few billion years, the barycenter will reside in free space, outside the Earth. The IAU, at that time, can then reclassify the Moon as a 'planet.' "
"Of Time and Space and Other Things"
Which was a collection of essays on various interesting science stuff, though I don't know if any of it was published seperately.
From http://www.psych.utoronto.ca/~peterson/primate/ch
So, no, humans aren't even exceptional in the capacity for murder.
Fanatically anti-fanatical
You're probably one of those people who also complains about slashdot stories being old news and out of date. Now slashdot gives you a story a few billion years early and you complain about that, too. Sheesh, some people are never satisfied.
- None can love freedom heartily, but good men; the rest love not freedom, but license. -- John Milton
But you would not. Every other moon in the solar system gives you a spirograph like thing. Earths moon produces a uniquely boring patern: more or less an elipse, just a bit wobbly. Other moons curve away from the sun as they circle around the far side of their planet. Our moon always curves toward the sun, just slightly less tightly. If there is a "double planet" in our solar system, it is clearly Earth-Moon, not Pluto-Charon.
There once was an orbiting entity /.-ers snickered
Neither planet nor moon in identity
The IAU bickered
It was too close to Earth; no Pluton, pity.
Give a man a fish and you have fed him for today. Teach a man to fish, and he'll say "WHERE'S MY FISH, YOU IDIOT?"
Did you guys not read about the barycenter of gravity? Read the AU's definition. http://www.iau2006.org/mirror/www.iau.org/NEWS.55. 0.html
The Earth-Moon isn't a double planet because the barycenter of gravity is clearly within the earth's surface because the size of the Earth is so much bigger than the Moon.
However, Pluto and Charon's barycenter of gravity is on the outside of Pluto's surface. That is why Pluto-Charon is a double planet, but not Earth-Moon. It's scientific, not arbitrary.
"So what planet are you from?"
"I am from planet Moon."
"What?"
"@#)$*(@#($&*(, I told you LAST TIME What's on second!!!! Graaaah!"
You see? You see? Your stupid minds! Stupid! Stupid!
THIS IS CETI ALPHA FIVE!!!
</Obligatory-Quote>
"Times have not become more violent. They have just become more televised."
-Marilyn Manson
Yeah, I know. Changed to Urectum.
The Moon cannot escape the Earth's gravitational field (unless there is a very large external perturbation). As the Moon slows it will orbit increasingly farther out, UNTIL it is traveling too slowly to maintain any orbit, at which point it will spiral in until broken up by tidal forces. Earth will get rings (and more than a few major impacts). If the Moon were traveling at escape velocity, it would already have departed. Since it isn't, it can't (on its own).
There may be a bit of a race condition between the Moon's orbital mechanics and the Sun's progression along the "Main Sequence", which will put it into a "red giant" phase where the extended "surface" may be near, or beyond, Earth's orbit. At that point, both parts of our Earth-Moon system will experience significant drag and spiral into the Sun's core.
Moving away at its current speed, it would have taken 10bn years to move from the Roche limit to its current position. (In rough figures: 4*(10^8)m / (0.04m/year) = 10^10years)
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.
If Apple conquers it, it will be called iMoon. If Microsoft conquers it, it will be called Microsoft Genuine Satellite. If GNU conquers it, it will be called MOON (MOON Orbiting Our plaNet). If KDE conquers it, it will be called KMoon.
Stupidity is like nuclear power, it can be used for good or evil. And you don't want to get any on you.