ASTR BC 1753x Lecture Notes - Lecture 4: Orbital Period, Vogon, Dailymotion
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Slimy creatures were not allowed to evolve after emerging from the sea. No, because unless your environment is totally stable, you need to be able to adapt. Hw #1 is due at the beginning of class on tuesday. Apparent position of a nearby star changes relative to distant stars during the earth"s orbit. Earth does not orbit the sun; it is the center of the universe. Due to earth"s orbit around the sun every 365 days. The percentage of the moon illuminated by the sun as seen from earth. When getting bigger, it"s called waxing versus getting smaller it"s called waning. Moon"s orbit about earth is tilted relative to earth"s orbit around the sun. Always see the same side of the moon. The shadow of the earth on the moon. The earth, moon and sun are not always perfectly aligned. When either passes through the other"s shadow, we get an eclipse.