What if I weren't?
No, I'm not that kind of curmudgeon. In actuality, it appears that the moon was the result of a collision between a couple of protoplanets in Earth's orbit during the accretion phase, 4.4 bya. The smaller body, called Theia, was probably at a trojan point of the sun/Earth system. That's a stable orbit, so long as the mass of Theia was small compared to earth. However, it appears the Earth reached about 2/3's its present size and Theia grew to 1/3, and as a result started oscillating away from the trojan point, eventually oscillating so much it fell into their mutual gravity pool and crashed into Earth with a glancing blow. The result was that Theia's core stayed and added to Earth's core, and a lot of Theia's mantle (and some of Earth's) was blasted into orbit. In the next several hundred years the moon coalesced from the orbiting debris into an orbit about 22.000 miles out from Earth as a stony, iron-poor, but relatively large satellite. The Earth gained a larger iron core than is normal, and it's spin was increased to the point of ten hour days. Since then, shift in rotational momentum has slowed the Earth's spin and increased the size of the moon's orbit.
No, I'm not that kind of curmudgeon. In actuality, it appears that the moon was the result of a collision between a couple of protoplanets in Earth's orbit during the accretion phase, 4.4 bya. The smaller body, called Theia, was probably at a trojan point of the sun/Earth system. That's a stable orbit, so long as the mass of Theia was small compared to earth. However, it appears the Earth reached about 2/3's its present size and Theia grew to 1/3, and as a result started oscillating away from the trojan point, eventually oscillating so much it fell into their mutual gravity pool and crashed into Earth with a glancing blow. The result was that Theia's core stayed and added to Earth's core, and a lot of Theia's mantle (and some of Earth's) was blasted into orbit. In the next several hundred years the moon coalesced from the orbiting debris into an orbit about 22.000 miles out from Earth as a stony, iron-poor, but relatively large satellite. The Earth gained a larger iron core than is normal, and it's spin was increased to the point of ten hour days. Since then, shift in rotational momentum has slowed the Earth's spin and increased the size of the moon's orbit.
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Because it is possible that if this did not happen we would probably not be here to be fascinated by it.