Moon’s Orbit Around the Earth We have mapped and named the moon’s features: Oceans, Seas (mare) (Not really oceans) Craters

No matter which phase, we always seems the same features: the same side of the moon

Why are we not able to see the “back” of the moon from Earth? We always see the same side, with the same features?

The back or the ‘dark side’ of the moon The visible “front”

Use the model of the Earth and the Moon to determine how it is that the moon can orbit the Earth and yet only ONE SIDE faces us all the time?

The Moon is in a The Moon is in a synchronous orbit around Earth. It rotates once on its axis every It revolves (orbits) around the Earth in It rotates once on its axis every 27.3 days, It revolves (orbits) around the Earth in 27.3 days. It’s “DAY” and “YEAR” ARE THE SAME: SYNCHRONIZED! This means we only see of the Moon. This means we only see one side of the Moon.

Sidereal month 28 days 28 days Time it takes for the moon to make one complete revolution around the earth and return to the same starting point. Time it takes for the moon to make one complete revolution around the earth and return to the same starting point. 28 days

Synodic Month 29.5 days Time for the moon to complete one full cycle of phases as seen by Earth Because in it’s orbit, the moon must go a little farther to ‘catch-up’ and complete on full cycle. Because the earth has moved in it’s orbit, the moon must go a little farther to ‘catch-up’ and complete on full cycle days

Tides The moon's gravitational pull on the Earth is the main cause of the rise and fall of ocean tides. The moon's gravitational pull on the Earth is the main cause of the rise and fall of ocean tides. The moon's gravitational pull causes two bulges of water on the Earth's oceans The moon's gravitational pull causes two bulges of water on the Earth's oceans where ocean waters face the moon and the pull is strongest and one where ocean waters face away from the moon and the pull is weakest. where ocean waters face the moon and the pull is strongest and one where ocean waters face away from the moon and the pull is weakest.

Super-moon The moon’s orbit is NOT a perfect circle The moon’s orbit is NOT a perfect circle A super-moon is a full moon or a new moon with the CLOSEST approach the Moon makes to the Earth on its elliptical orbit, resulting in the largest apparent size of the lunar disk as seen from Earth. A super-moon is a full moon or a new moon with the CLOSEST approach the Moon makes to the Earth on its elliptical orbit, resulting in the largest apparent size of the lunar disk as seen from Earth.full moonnew moonMoonfull moonnew moonMoon