Eclipse of The Moon

Lunar Eclipse Page

Lunar Eclipses occur when the Moon moves into the shadow of the Earth. This drawing is not to scale. Proportionally, the Sun is much larger and much, much further away from the Earth, and the Moon orbits the Earth at a much greater distance. The shadow of the Earth takes up only a very small angle of the moon's orbit, and the moon's orbit only crosses the shadow of the earth near the time of the equinoxes. Therefore, lunar eclipses are fairly rare.
Trivia Questions

Lunar eclipses occur in what phase of the moon?
How often is the Space Shuttle usually eclipsed when in orbit?
Where is the Moon during a Solar eclipse?
What design considerations would a satellite designer have to accomodate eclipses?
Can everyone on earth see a lunar eclipse?

Can more or fewer people see Solar eclipses than Lunar eclipses?

Lunar Eclipse Photos

Photo Credits: Charles Barnes - Taken Sunday 23 March 1997
Canon EOS Rebel, Kodak Royal Gold 400 film and a 2000mm/f10 Celestron telescope with a telephoto adapter.
The first shot was taken at 10:19 EST 1/60 sec. The Second at 10:39 EST 1/60 The Third at 10:59 EST 1/60 The Fourth at 11:19 EST 1/60 The Fifth at 11:39 EST 1/30

Last revised on by Ted Schober
Copyright © 1997 New Jersey Wing Civil Air Patrol

The Moon must be Full. The night side of earth will see the sun's reflected rays over the full surface ot the moon, until it passes into the earth's shadow.

Once Per Orbit. The Space Shuttle orbits only a few hundred miles above earth. The earth's shadow takes up a substantial portion of the Shuttle's orbit.
Polar orbits can be designed to avoid eclipse. One special type of polar orbit is called the sun synchronous orbit. It can be designed so that it passes over earth at some position the same time of day every orbit.

The Moon is directly between the Sun and the Earth. To make a shadow on the Earth, the Moon must block the Sun's rays from reaching the Earth.

A satellite will receive no sunlight. The solar cells will receive no energy for the duration of the eclipse. There must be adequate battery power to keep the satellite functioning for the duration of the eclipse, and they must be able to be fully recharged by the next orbital eclipse.
The satellite will also suddenly get a lot colder when entering eclipse, and suddenly get a lot hotter when coming out of eclipse. The designer must compensate for these thermal cycles and stresses.

Only the area where the Moon is risen will see the eclipse. Anyone on the day side of the earth will not be able to see the moon, and people near the terminator (the line between night and day) will only see the moon if the horizon is clear.

Lunar eclipses may be seen by almost half the earth. The Moon must be centered over the night side of the earth for an eclipse to be seen. This will assure that the moon is risen over most of the night side of the earth.
In Solar eclipses, on the other hand, the shadow made by the moon is fairly small (because the Moon is smaller than the earth) and only a swath across the earth will have the full eclipse visable.