The moon is 1/400th the size of the sun but also 1/400th the distance from Earth which results in the moon and the sun being the same size in the sky, a coincidence not shared by any other known planet-moon combination.

submitted by Orangutan from (earthsky.org)

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[–]Tom_BombadilBombadildo 1 insightful - 1 fun1 insightful - 0 fun2 insightful - 1 fun -  (0 children)

This fortuitous coincidence was used to prove special relativity. During an early 20th century eclipse a star could be seen that was actually behind the sun, because if the lensing/bending effect of the sun's gravity.

This is a truly astounding coincidence. Almost to good to be true. Gives credence to the simulation reality theory. All of the necessary conditions are in place for generations of simulated lives, and it's possible that we are an alien species similar to "Roy" on Rick and Morty.

[–]RoxannaHardbutt 1 insightful - 1 fun1 insightful - 0 fun2 insightful - 1 fun -  (5 children)

..the Moon and the Sun being the same size in the sky, a coincidence not shared by any other known combination.

I disconcur .. the sharp eclipse shadows photographed on planet Jupiter by various spacecraft, indicate the eclipsing body and the Sun are the same relative size in the Jovian sky, just like the Sun and the Moon seen from Earth.

[–]Tom_BombadilBombadildo 2 insightful - 1 fun2 insightful - 0 fun3 insightful - 1 fun -  (4 children)

I disconcur .. the sharp eclipse shadows JPG photographed on planet Jupiter by various spacecraft, indicate the eclipsing body and the Sun are the same relative size in the Jovian sky, just like the Sun and the Moon seen from Earth.

The "sharpness" of the eclipse shadows has nothing to do with the angular diameter/area that a planet's moon(s) occupys in the sky from a given location

If the Earth's moon were closer in orbit, then it's angular diameter would increase. If it were farther, then the angular diameter would decrease.

The fact that the moon and the sun have equal angular distances is almost incredible. Literally.

The Earth's moon is quite large relative to the size of the Earth..

The Earth is much smaller than Jupiter.

[–]RoxannaHardbutt 1 insightful - 1 fun1 insightful - 0 fun2 insightful - 1 fun -  (3 children)

The well defined eclipse shadow seen on Jupiter does indeed prove the eclipsing body subtends the same angle in the sky as the Sun, a similar sharp shadow has been imaged on planet Uranus during an eclipse by its satellite Ariel proving both bodies have the same angular dimension, that eclipses on planet Mars never produce sharp shadows is because neither of its moons has sufficient angular width to cover the disc of the Sun, likewise if the eclipsing bodies on Jupiter and Uranus were smaller or larger their shadows would never be in focus. Edit.

[–]Tom_BombadilBombadildo 1 insightful - 1 fun1 insightful - 0 fun2 insightful - 1 fun -  (2 children)

Subtending is irrelevant as light from the sun at these distances can be considered parallel rays; for all practical purposes.

[–]RoxannaHardbutt 1 insightful - 1 fun1 insightful - 0 fun2 insightful - 1 fun -  (1 child)

You'll be on about the Flat Earth next ..

[–]Tom_BombadilBombadildo 1 insightful - 1 fun1 insightful - 0 fun2 insightful - 1 fun -  (0 children)

Accretion disk. Not Earth.

[–]Vigte 1 insightful - 1 fun1 insightful - 0 fun2 insightful - 1 fun -  (2 children)

"There are more reasons why the moon should NOT be there, than there are for it to be there" - Randall Carlson (I think?)

[–]Tom_BombadilBombadildo 2 insightful - 2 fun2 insightful - 1 fun3 insightful - 2 fun -  (1 child)

Maybe. Most planets have them, so that's weird.

I bet that the planets that do have them, don't appreciate them. Ceaselessly hovering around. Following them everywhere they go. They're already thinking the moons aught to quit following them around, and give them some space (as if there isn't enough space to go around).

They're wrong though. Unbeknownst to them, the moons provide them with an active lifestyle. Just look at Mars. He's now waiting to get the divorce paperwork finalized, and he's practically a dead planet.

Jupiter is the notable exception. That attention hogging jerk will take anything he can get, and more. Don't let your moon hang around that guy. Friggin guy once even ate his kids, it so I'm told!!!

For Christ's sake Jupiter! You bigamist bastard!

[–]Vigte 1 insightful - 1 fun1 insightful - 0 fun2 insightful - 1 fun -  (0 children)

Bravissimo!