Eclipses (23)

Eclipses occur when the moon or sun moves into the moon’s or Earth’s shadow. Parts of a shadow: –Umbra: total shadow – complete eclipse. –Penumbra: partial shadow – partial eclipse (dimmed).

Lunar Eclipse Can ONLY happen during a full moon. Moon moves into earth’s shadow.

Lunar Eclipse (cont.) Moon moves into the penumbra and dims. As it gets closer to umbra it gets darker. Typically lasts about 2 hrs.

Lunar Eclipses (cont.) Some light coming around the earth can make the moon look red/brown. About 2 lunar eclipses/year. Easy to see, needs to be night time (where you are) when the moon passes through the earth’s shadow.

Next lunar eclipse will be June 4 th (partial). Also one on Nov. 28 th but we won’t be able to see it here.

Solar Eclipse May only occur during a new moon. –Sun is in moon’s shadow.

Solar Eclipse (cont.) Total solar eclipses are rare to see because the moon’s umbra is small. –Outside of the moon’s umbra no eclipse is seen. –Becomes so dark other stars can be seen. –Last only a few min.

Solar Eclipses (cont.) Last solar eclipse: July 11, 2010 –Seen only from the Pacific Islands and South America. Next solar eclipse we can see: August 21, 2017.

Frequency of Eclipses 1.Earth’s and moon’s orbits are elliptical. Distances between them vary slightly. Shadow sizes change. 2.Moon’s orbit is tipped slightly to earth’s and it often misses the earth’s shadow.

Eclipse Foldables (22) Each Foldable needs: –Term, Explanation, & Illustration. Umbra Penumbra Solar Eclipse Lunar Eclipse Answer the following questions at the bottom of your page: 1.Give 2 reasons why eclipses don’t happen more often. 2.Why is it more rare to see a solar eclipse than a lunar eclipse?