They do actually appear the same size in the sky though, which is why we get perfect eclipses. The Moon is slowly getting further away from Earth so it won’t be forever. We’re just in a lucky moment of time in the universe.
I know you’re right, have read it elsewhere before. But I can’t figure out why that would happen. I doubt Earth is loosing mass. Does the moon slow down over time due to impacts or what causes this?
If it slowed down it would get closer, not further. The truth is, any orbit is only stable given a specific timeframe. The longer that timeframe, the less likely any given orbit is to remain. The moon has just a little bit more speed than the Earth can hold onto, so it is in an extremely slow escape, and always has been.
If it had a stable orbit before and then slowed down, I thought it’ll get a more elliptical orbit, being both closer and further, or fall into Earth.
My logic was that a stable orbit closer to the center needs higher speeds to counter higher gravity and vice versa.
So if the moon would get hit in a way that makes it slow down and get pushed further away from Earth at the same time, it could keep a roundish orbit, or not?
What’s with that specific timeframe? Is it due to the orbit never being perfect? Or random slight influences from other not too far, heavy objects?
Thanks for the explanation, the moon being a little fast for it’s orbit and therefore slowly spiraling out of Earths gravity makes sense to me now.
The moon has just a little bit more speed than the Earth can hold onto
Unfortunately that’s not how orbital mechanics works :(
If the moon had instantaneously more speed than the earth can hold onto (e.g. more centrifugal ‘force’ than balanced by the gravitational force), the moon will accelerate up, until the forces become balanced. This makes a elliptical orbit, like this: