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Keira B,

Why the big difference in lunar eclipses vs. solar eclipses?

Hi.
In the case of a solar eclipse an object which glows (the Sun)  is being hidden from view. This allows us to see fainter parts of the Sun which are not hidden - especially the beautiful solar corona. To see a solar eclipse you have to be lined up just right with the Sun and the Moon. Because the Sun is still glowing it will look normal from any other point of view.

The Moon is only visible because it reflects light. During a lunar eclipse the Moon is cut off from the light of the Sun by the shadow of the Earth so that the Moon becomes dark. You can see a lunar eclipse from anywhere you can see the Moon, because without the Sun's light falling on it the Moon really is dark.

Hope that helps,
Terry

Hi Keira,

Terry said something that I thought was very nice - that in a lunar eclipse since the moon is not glowing by itself, the Earth blocks the light from the Sun to make a lunar eclipse.  There are many people who think this is also how the phases of the moon are made - from Earth blocking the Sun's light.  But it is not.  If it were true, lunar eclipses would not be such a special thing. 

The phases of the moon are related to how we see the side of the moon lit by the Sun and the side in darkness.  The moon is always half in sunlight and half in darkness.  Sometimes we see the moon from a perspective that allows us to see its entire sunlit side (full moon).  Othertimes we see the moon from a perspective that allows us to see half its sunlit side while the other half we "see" is dark and not visible (first quarter or last quarter).  And sometimes we don't see the moon at all because its from our perspective all we can "see" is its darkside (new moon).

Laura

Hi Keira,

Another important difference between solar and lunar eclipses that was not pointed out in the earlier posts is that there is an enormous difference in the duration and visibility of a total lunar eclipse and a total solar eclipse.

A lunar eclipse happens only when the Moon is full, and the lunar eclipse is visible from basically everywhere on the night side of the Earth. As long as the Moon is within the Earth's shadow, everyone on the night side of the Earth will see the eclipse. It takes about 1 hour and 42 minutes for the Moon to travel through the deepest part of the Earth's shadow, so this is the maximum possible period of totality for a lunar eclipse.

For a total solar eclipse, totality can last for only up to about 7 minutes and 30 seconds. A solar eclipse is only visible in a narrow strip on the Earth's surface, called the eclipse path. This is because the size of the dark spot on the Earth's surface created by the Moon's shadow is only about 65 miles in diameter. The dark spot will move across the surface of the Earth very rapidly due to the rotation of the Earth on its axis, so a total solar eclipse lasts for only a short period of time.

These times are only the maximum possible lengths of totality based upon the Moon's orbital motions and the speed of the Earth's rotation. Most eclipses have shorter periods of totality.

Kris