Lesson: A SOLAR ELCLIPSE occurs when the Moon blocks the Sun's light from some area on the EARTH. Because the Earth and Moon shine only by the reflected light of the Sun, the Earth and Moon which they each cast a shadow into space in the direction away from the Sun. This consists of two things. One is a cone-shaped area of complete darkness, called the UMBRA. The other is much larger, it's called PENUMBRA, which is an area of partial darkness that surrounds the UMBRA. Total Solar Eclipse's occur when the Moon's umbra reaches the earth. The length of the moon's umbra varies from (228 to 236) thousands of miles. The moon is about (220-250) thousands of miles away from earth. The diameter of the umbra is close to 170 miles, which is considered narrower for viewing. The view of the PENUMBRA shadow is much greater, about 3000 miles. At certain times when the moon passes between the Earth and the Sun, it's shadow does not reach the Earth. At these times an Annular Eclipse occurs in which an (annulus) or bright ring of the solar disk appears around the dark disk of the moon. Solar and Lunar Eclipse's are possible only when the moon crosses the Earth's orbital plane at a time when the Sun, Moon, and Earth are in alignment, at new or full moon.
Homework
Take notes over the lesson. It doesn't have to be very much. Just find 3 important pointers in the lesson or more.
