Unlocking the Moon's Secrets: From Galileo to Giant Impact

The Moon is the most viewed object in the sky, the Sun being too bright to look at directly and the planets too far away. The Greeks deduced everything that could be learned about the Moon using only the naked eye, including that it has no light of its own but reflects that of the Sun. They understood the cause of eclipses and used the Earth's shadow on the Moon to conclude that our planet is a sphere and to calculate the size of both the Moon and the Earth. The invention of the telescope s...