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A moon fact…
• From space, the Earth and our moon appear to orbit each other!
Eugene Cernan – last man to walk on the moon!
Lunar Orbit and Rotation• The moon’s orbit is an ellipse
• Apogee: when the moon is farthest away
• Perigee: when the moon is closest
This is the difference between a perigee and apogee moon!
Lunar Orbit and Rotation
• The Earth’s rotation causes the moon to “rise” and “set”
• The moon rises 50 minutes later each night
Why do we only see one side of the moon?
•The moon’s rotation and revolution take the same time!
The far side of the moon – taken by Apollo 17 astronauts
Eclipses• Occurs when one
planetary body passes through the shadow of another
• Umbra: inner shadow• Penumbra: outer shadow
Eclipses• Only those is in the umbra
see the total eclipse!
• Each can happen up to 4 times a year
Solar Eclipses–moon comes between earth and the sun, leaving its shadow
–In the umbra, total eclipse
–In the penumbra, partial eclipse
A total solar eclipse!
A partial solar eclipse!
This solar eclipse shows flares (storms) on the edges
of the sun!
Solar Eclipses•Annular eclipse: ring shaped, occurs when moon is at or near apogee (farthest away)
•Last only up to 7 minutes•More common than a lunar eclipse
An annular solar eclipse!
A series of photos of a solar eclipse!
The moon’s shadow moves across Earth!
Lunar Eclipses• Earth comes between moon
and sun• Visible to anyone on the side
of the Earth facing the moon• Total lunar eclipse: passes
in the umbra
Lunar eclipse – time elapsed pictures
Lunar Eclipses• Partial lunar eclipse: only
part passes in the umbra• Penumbral lunar eclipse:
passes in the penubra• Lunar eclipses can last
several hours
Lunar Eclipses• Seen by more people than a solar eclipse
• Why?
• The Earth’s shadow is bigger than the moons!
Historical Solar Eclipses
• 763 BC: The earliest recorded solar eclipse that has been accurately identified.
• The Greek Herodotus wrote about a solar eclipse that occurred, causing two armies (the Medians and the Lydians) to lay down their weapons and resolve their differences peacefully. The exact date is not known. It is likely to have been in 585 BC
Historical Solar Eclipses
• 478 BC: an annular eclipse occurred as Xerxes (king of Persia) left to battle Sparta in the battle of Thermopylae
• (Remember, the movie 300?)
• 1879: Zulu warriors defeat a British battalion during a solar eclipse
• 1919: a solar eclipse helps confirm Einstein’s theory of general relativity.
Historical Lunar Eclipses
• 1453: One occurred during the fall of Constantinople (Istanbul, Turkey) – it was seen as a bad omen, predicting doom
• 1504: Columbus knew of the prediction and used it to convince the natives of Jamaica of his power; they continued to feed and house Columbus’ men
• 1573: Tycho Brahe predicted it
