A coincidence I have a problem with.

[Stu Pidasso]

I've heard it described as a "stunning stellar coincidence" that the moon exactly covers the sun during a solar eclipse. The actual "coincidence" is that the sun, which is 400 times larger than the moon, just happens to be 400 times further away from the earth than the moon.

Fourth graders used point out that the shapes of continents on a world map fit together like puzzle pieces. This was also dismissed as merely a fantastic coincidence until the discovery of plate tectonics.

"Fantastic" or "stellar" coincidences bother me. I suspect there is a better explanation for why we have such perfect eclipses.

Stu

[eviljeff]

if you were to illustrate the coincidence that the sun is 400x the size of the moon and also 400x further away from Earth, how would you do it?

[pookvis]

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if you were to illustrate the coincidence that the sun is 400x the size of the moon and also 400x further away from Earth, how would you do it?

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MS Paint

[Stu Pidasso]

whoops wrong forum..

Now cross posted in SMP. Mods feel free the lock or delete this thread.

Stu

[suzzer99]

I believe the current theory is that the moon formed when the early earth, and another large planetary object collided. A chunk flew off from the collision and became the moon. The rest conglomerated to form the earth. Also the leftover heat from this collision is what gives the earth it's molten core.

So it's hard to see how any pattern could exist if the moon is really just a random chunk of stuff that came out of a big collision. But who knows.

[offTopic]

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whoops wrong forum..


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Coincidence?

[ArcticKnight]

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if you were to illustrate the coincidence that the sun is 400x the size of the moon and also 400x further away from Earth, how would you do it?

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I'd start with the ratios of other planets and their satellites (to the sun) in our solar system. It's our only comparitive bench mark.

I'd also look to see if the ideal orbit for any satellite is linked to it's mass. That is, if the moon was smaller, would it likley be closer, thus having near the same effect in relative diamter to the sun during an eclipse.

[Arito]

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I suspect there is a better explanation for why we have such perfect eclipses.

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I don't understand. Like what?

[suzzer99]

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if you were to illustrate the coincidence that the sun is 400x the size of the moon and also 400x further away from Earth, how would you do it?

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I'd start with the ratios of other planets and their satellites (to the sun) in our solar system. It's our only comparitive bench mark.

I'd also look to see if the ideal orbit for any satellite is linked to it's mass. That is, if the moon was smaller, would it likley be closer, thus having near the same effect in relative diamter to the sun during an eclipse.

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Yeah but the Earth and Venus are very close to the same size, and Mars is smaller than the Earth, but Jupiter is much bigger. So that sort of blows the possible size->orbit connection.

Apparently the way the major planets formed is by gathering up all the stuff in their immediate vicinity. Sort of like an orbiting version of flakes coalescing in a cereal bowl. There's a lot of randomness to the process in terms of how much material exists in each disk, and how soon a massive ball starts sucking the other objects up.

[CallMeIshmael]

Beyond that the fact that they arent *that* close, you have to realize that this is just cherry picking out of a huge data set of "non coincidences," in as much as nature is full of of all sorts of things that dont work out so cleanly.


I mean, if you throw a few million handfulls of 20 coins on the ground, some packets will come up w/ 20 heads. Looking just at that, yeah, it looks pretty odd. But you need to ignore all the other ones.