Study Notes
Umbra: The darker part of the shadow in an eclipse. It is CONE shaped
Penumbra: The lighter part of shadow and it the LARGER part of the shadow.
* Lighter and Larger*
-----------------------------------------------------------------------------------------------------------Lunar Eclipse: When Earth is between the sun & the moon. The Earth blocks the
sunlight from hitting the moon. Occurs during a FULL MOON.
As the moon reaches line A it begins to enter the Earth's shadow. Part of the sun is still
shining on it so it is not totally dark.
At line B the moon is about half dark. Some of the sun's light seeps through the Earth's
atmosphere and turns the shadow reddish.
At C the moon is coming out of the darkest part of the shadow.
At D the moon is fully lit again. It takes about 5 hours to move from line A to line D.
Solar Eclipse: When the moon is between the Sun and Earth. The moon blocks
sunlight from hitting Earth. Occurs during a NEW MOON.
The diagram below shows the moon's shadow covering part of the Earth.
Lines A and B are where the sun's light is blocked by the moon. Again, the drawing is
not to scale. Solar eclipses happen from about 9 to 30 months apart.