Lunar Phases, Eclipses, and Tides

Moon Orbits the Earth – but appears to rise in the ____ and set in the ______due to earth’s faster rotation

Moon’s Rotation = Moon Revolution  rotation period = ______days  revolution period = ______days  Moon shows the same “face” to the Earth  Velocity: 360°/27.3 days = ______per day

Daily Movement of the Moon • Each day the Moon rises in the east and sets in the west as a result of the Earth's ______.

• It moves about 13° eastwards against the background of stars as a consequence of its ______around the Earth.

Moon Phases  Half of the moon is always receiving light ______.  The “_____” portion that is visible to earth varies as the moon ______around earth. THIS CAUSES THE ______OF THE MOON.  Visible portion of moon growing = ______ Visible portion of moon shrinking = ______Lunar Phases How much of the moon we see depends on ______

Cycle of Lunar Phases  Takes ______days  This is because when moon gets back to its original position in 27.3 days, the earth has moved 1°/day or about 27°.  The moon moving at l3°/day takes about ____ days to catch up with Earth and align with it and the sun in a new moon phase. Lunar and Solar Eclipses The Moon orbits the Earth, and travels with the Earth about the Sun.

Sometimes the _____gets between the Earth and the _____, causing solar eclipses, and sometimes the Moon goes into the Earth's shadow, causing ______eclipses.

Solar Eclipses – can occur only during the ____ moon phase Lunar eclipses – can occur only during the ____ moon phase

If Lunar eclipses happen in the full moon phase and solar eclipses happen in the new moon phase, why don’t they happen every month??? As the Moon orbits the Earth, its orbit is tilted slightly (about 5 degrees) from earth’s orbital plane (ecliptic)

The moon crosses earth’s plane twice during its orbit. If this crossing happens at the new moon phase, the Moon will be lined up with the Sun and pass in front of it.

This alignment has to be perfect in order for the Moon to completely cover the Sun for a total solar eclipse (the sky will darken just like nighttime, and the stars will be visible) Total solar eclipses last about 7 minutes and occur in a very narrow range across Earth. Full moon phase = total lunar eclipse if perfect. Solar Eclipses Occur when moon’s orbit intersects ecliptic during the new moon phase

Total Solar Eclipses only last about 7 minutes in a very narrow range across Earth Daily Cycle of Tides  Driven by the gravitational pull of the ______ Affected by nearness of the ______more than the size of the Sun  As earth rotates, the tides move around the Earth alternating between high and low tides approximately ______hours.

Spring Tides – Neap Tides  Tidal range: Difference in height between high tide and low tide

 ______: new and full moon phase – greatest range

 ______: 1st and 3rd Quarter phases – smallest range