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Lunar eclipse...in Year 6 Science

A lunar eclipse occurs when the Moon passes directly behind the Earth into its umbra ( shadow ). This can occur only when the Sun, Earth, and the Moon are aligned exactly, or very closely so, with the Earth in the middle. Hence, a lunar eclipse can only occur in the night of a full moon. The type and length of an eclipse depend upon the Moon's location relative to its orbital nodes. Unlike  a solar eclipse, which can only be viewed from a certain relatively small area of the world, the lunar eclipse may be viewed from anywhere on the night side of the Earth. A lunar eclipse lasts for a few hours, whereas a total solar eclipse lasts for only a few minutes at any given place, due to the smaller size of the moon's shadow. Also unlike solar eclipses, lunar eclipses are safe to view without any eye protection or special precautions, as they are no brighter than the full moon itself.

The shadow of the Earth can be divided into two distinctive parts : the umbra and penumbra. A partial lunar eclipse occurs when only a portion of the Moon enters the umbra. When the Moon travels completely into the Earth's umbra, one observes a total lunar eclipse. The Moon's speed through the shadow is about one kilometer per second. The toatal time between the Moon's first and last contact with the shadow is much longer, and could last up to 4 hours.

 ( Adapted from http://en.wikipedia.org/wiki/Lunar_eclipse )

Watch the video clip of lunar eclipse...


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