Welcome To My Darkness - May 21st, 2005
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01:31 am
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We Like Da Moooon!
DID YOU KNOW?
That scientists are unsure how exactly the moon came to orbit around the Earth! It is seen as very unlikely that the Moon formed along with the Earth or even that the Moon was captured later!
Some Scientists long believed that the cetrifugal force of the Earth caused the Moon to break off, leaving one of our oceans as a gaping scar. However, this theory would require too much of an initial spin on the Earths part. Plus, of course, the composition of the Moon is different from that of the Earth.
Others speculated that the moon was captured into the Earths gravity and brought into orbit, however, the chances of that seem pretty minimal.
(Edit: See comments for the reasons why)
Some propose the Coformation or Condensation Theory. This states that the Earth and Moon were formed at the same time from the accretion disk (A disk of interstellar material surrounding a celestial object with an intense gravitational field, such as a black hole). But this theory cannot explain the depletion of Iron in the Moon.
Others suggest that the Moon formed from a debris field around Earth resulting from an asteroid or planetesimal collision.
The currently accepted theory is the "Giant Impact Theory", which states that the Moon originated from what was ejected when Earth, in its' semi-molten stages, collided with an object about... er... the size of Mars! (theoretically called Theia.) But I'm usure of the theories likelihood, as if the chances of a Mars-sized object hitting the Earth are small enough, that chances of it hitting Earth at angle which didn't destroy it entirely are minute! Infact, if this is what occured then it is this incident which is responsible for the fortunate degree of axial-tilt and plate teutonics (which are vital to the carbon cycle) of Earth which makes life here possible! And can therefor used as a theory to explain the apparent rarity of life in the universe.
More scary to think that if these infinitessimally unlikely events are the cause of life on Earth... then we may indeed be alone in the galaxy, a concept I've always regarded as improbable if not ludicrous.
In technical terms, the Earth and Moon are a "binary planet": that means the moon isn't technically a Satellite of the Earth because the centre of gravity (and centre of mass, which is always at the same point as the centre of gravity) is at a point in between the two, rather then somewhere inside the Earth.
I also heard, but have no science to back up, that the Moon is too large / has too high a mass and is too close to the Earth to scientifically justify its' orbit! Wouldn't that be freaky? Kind of like how the flight of a bumble bee is meant to be scientifically impossible when you compare it's wing span and the frequency at which it flaps them wings to it's weight.
In short, there are a bunch of really unlikely theories as to how the Moon came to orbit the Earth, and perhaps one of them is infact correct... or maybe we just don't have the means to determine the real reason yet.
Call me a geek (and I shall not deny it!) but I find this stuff WICKED COOL.
I wrote and researched this article myself, now adore me for it!
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