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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."
Plus the human race will have rendered the Earth uninhabitable by then so there'll be nobody to care...
No-one knows if the humans will survive that long, maybe there will be no-one to rename it.
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.
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.
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.
Heretofore a planet was (loosely) defined as a large mass in orbit around a star. In our solar system the primary tenet of planethood was that the object orbited the Sun rather than orbiting a body which orbited the Sun. There are other conditions, of course, because not everything that orbits the Sun is a planet but it's a good place to start. Simply put though, if an object doesn't meet the criteria of a) orbiting the sun and b) being of a certain size or larger it doesn't make the cut. If the IAU dispenses with or at least loosens those two historical criteria the solar system will suddenly be filled with planets and confusion (at least amongst the non-astronomer crowd) will ensue. That's the real problem. I think there is more to think about than simple semantics.
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
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
Unless of course he happens to be an oyster or something...
http://en.wikipedia.org/wiki/Egg_(biology)
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.
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
Ditto for Pluto and Charon.