Tuesday, May 22, 2007

An Artificial Moon

It's not a new theory but more and more scientists are starting to venture into the question of how and why the Moon exists. A number of explicit coincidences have fascinated astrologists. For example, the Moon is exactly four hundred times smaller than the Sun but four hundred times closer to the Earth so that both the Sun and the Moon appear to be precisely the same size in the sky. This coincidence makes possible the phenomenon of a total eclipse. Whilst we take this for granted, scientists hail it as the biggest coincidence in the universe.

The Moon also mirrors the movement of the Sun in the sky by rising and setting at the same point on the horizon as the Sun does at opposite solstices. This means the Moon rises at midwinter at the same place the Sun does at midsummer. There is no logical reason why the Moon mimics the Sun in this way and it is only meaningful to a human standing on the Earth.

The Moon also rotates exactly the same rate it is moving around the earth: 29.5 earth days. So you will only ever get to see one side of the moon. The other side of the moon is often dubbed 'The Dark Side of the Moon'.

Life as it is on Earth would be drastically different if not impossible without the existence of the Moon. There would be no seasons and no tides.

So is the Moon in fact placed in Orbit around the Earth by Intelligent Design? Well I wouldn't know for sure, but that seems plausible to me.

3 comments:

Anonymous said...

Intelligent design, /laff !

Julian said...

There are four main theories about the creation of the moon, although only one is generally considered to give an accurate description of what actually occurred.

The first theory states that the moon was created the same way the planets were - through the coalescing of gas and dust during the solar system's formation. The nice part of this is that there was a lot of material around in the early solar system for this to happen. However, this does not account for why Earth and Luna have different compositions, such as the moon lacking a significant amount of iron. Another con of this is that the Earth-Moon system has too much angular momentum compared to other planets for this to be a likely scenario.

The second theory says that the moon is a captured asteroid. The only "pro" of this is that it's not impossible. It is, however, extremely improbable. Besides the miniscule chance for this to happen, the energy that the moon would have had would need to have been carried off by a third body, otherwise the moon never would have parked itself in Earth orbit.

The third theory says that when the Earth was first formed it was spinning so rapidly that it split in two; this is often referred to the "fission" theory. This theory can account for why the density of the moon is similar to that of Earth's outer layers. Unfortunately for this theory, the moon would then be orbiting along Earth's equator, which it is not. Second, the composition of Moon rocks are dissimilar to that of Earth's surface. Finally, Earth would have had to have been spinning at a rate of about one rotation every hour and 25 minutes, as found by balancing the centripetal and gravitational forces:

5040 sec

The fourth theory is the one that most scientists currently believe is correct. It states that when the Earth was quite young, a Mars -sized planet crashed into it. The planet crashed with such speed that it was completely destroyed, and almost destroyed the Earth. The planet was coming in with such force that when it was destroyed, the molten iron in its core continued to travel through Earth, to eventually be included it its core. The crash, comically dubbed the "Big Splash," sent trillions of tons of rock and debris into orbit. These fragments eventually coalesced to form the Moon.

This theory has many pros, the first of which is that simulations confirm that this is what would happen in this situation, and that collisions in the early solar system did happen. This would explain why the moon has very little iron, and it also explains why there are very few volatiles in the moon. The tidal and rotational forces in play also would account for why the moon's day is exactly the same as it's "year." As a bonus, it also explains the tip in Earth's axis. Two cons are that in order to get material past the Roche limit, the impactor body would need more angular momentum than is now in the Earth-Moon system. Also, there is no reason in this theory why there should just be one moon, yet there is.

Ref: http://filer.case.edu/sjr16/advanced/earth_moon.html

Julian said...

oh there was an equation in there somewhere.

btw that was meant to proove, no it wasn't "placed"!!!! XD