1. Shadows

2. Shadows- areas light cannot reach due to an opaque object in light’s path. There are two parts to a shadow. Umbra- sharp black center of a shadow Penumbra- fuzzy gray outer portion of the shadow

4. Shadow Penumbra Umbra

5. These shadows cause eclipses When the Earths shadow falls on the moon you get a lunar eclipse. When the Moons shadow falls on the Earth you get a solar eclipse. If you are in the umbra you will see a total eclipse. If you are in the penumbra you will see a partial eclipse. http://www.forgefx.com/casestudies/pr enticehall/ph/eclipse/eclipses.htm

6. Solar Eclipse *This is not to scale

8. Not to Scale… These drawings are not to scale. Here is a picture showing the actual size of the Sun compared to the Earth and Moon.

9. Actual size of Astronomical Objects http://sciencenetlinks.com/interactives/messenger/psc/PlanetSize.html

10. ?!?!?! How can the Moon block out such a large object? The Moon is on average 385,000 km from Earth. The Sun is on average 1,500,000 km from Earth, or almost 400x further away. In our sky, both objects appear to be almost the same size. http://phet.colorado.edu/sims/gravity-and-orbits/gravity-and-orbits_en.jnlp

11. Homework Read sections 25.5 and 25.6 Pg 549 Questions 16-19; 26, 28-30, 42, 44, 45