August 17th will see a partial eclipse of the moon at around moon set for most of us here in Australia. If you live in Africa or Europe you will see it all and if you live in the US or Canada - you will miss it entirely. West Australia will see the most of anyone in Australia.
Unlike solar eclipses, it is quite safe to watch a lunar eclipse with the naked eye - though lots of warm clothes at this time of year are essential. Watching a lunar eclipse is actually better with the naked eye than through a telescope - because as the moon is full - there is little contrast.
A Lunar Eclipse occurs when part or all of the Moon passes into Earth's shadow. This doesn't happen every Full Moon though, because the Moon's orbit is actually tipped about 5° with respect to Earth's orbit around the Sun. This means that during most Full Moon's, the Moon is actually above or below the Earth's plane and therefore not in the shadow of the Earth.
A Partial Lunar Eclipse, such as this one is, occurs when only a part of the Moon passes into the Earth's umbral shadow. This type of eclipse accounts for 30% of all Lunar Eclipses. During this phase, a "chunk" or portion of the moon goes into shadow.
The first stage, which will begin around 4:25 am is called the penumbral stage - the contrast is very subtle and the shadow can be hard to detect at first. This occurs when the moon passes through the Earth's penumbral shadow.
The partial stage will begin at around 5:35am for most of us in Coonabarabran or Sydney and continue to moonset.
Photographing eclipses is quite easy with a digital camera. Check out mreclipse.com for ideas.
http://www.mreclipse.com/LEphoto/LEphoto.html
The next total eclipse visible from Australia will be Dec 21, 2010. Then we get to see 2 in 20011 and 2012 as well.
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