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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!
In a billion years propably the defintion of planet will have a few thousand updates.
The problem will fix itself in time I guess.
...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.
...and we will still be waiting to play Duke Nukem forever on our Vista machines.
liqbase
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.
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.
In fact we'll only be able to take one item of baggage, which will be a clear plastic bag containing essential items only.
And no electronic devices. Or Liquid.
Orbiting balls of rock won't even fit through the scanner.
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.
In about 5 billion years, when the Sun is a red giant, it will be so large that it will consume Mercury and Venus. Models predict that the Sun will expand out to about 99% of the distance to the Earth's present orbit (1 astronomical unit, or AU). However by that time the orbit of the Earth will expand to about 1.7 AUs due to mass loss by the Sun. Our planet will thus escape envelopment. -- Reference http://en.wikipedia.org/wiki/Star
We can just build a new moon. With blackjack. And hookers.
Don't blame me; I'm never given mod points.
Phew!
i ate crayons when i was a kid and now i have two braincells and the blue ones taste nicer
Consider 2 bodies of equal mass seperated by a distance of X.
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".
liqbase