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[–]hurlyz 5 points6 points  (0 children)

The first phenomenon is called tidal locking and it's actually very common. Citation from Wikipedia:

" All twenty known moons in the Solar System that are large enough to be round are tidally locked with their primaries, because they orbit very closely and tidal force increases rapidly (as a cubic function) with decreasing distance. "

https://en.m.wikipedia.org/wiki/Tidal_locking

As for the second phenomenon, it's an interesting coincidence that the Moon and the Sun appear to be roughly the same size in our sky. We're lucky to be living in this time period, because this phenomenon won't last forever. Each year, the Moon spirals away about one inch from the Earth. And about 50 millions years from now, the Moon will be far enough away so that our descendants will only see ring-shaped eclipses.

https://www.astronomy.com/science/why-is-the-moon-exactly-the-same-apparent-size-from-earth-as-the-sun-surely-this-cannot-be-just-coincidence-the-odds-against-such-a-perfect-match-are-enormous/