- Partial lunar eclipse, Saturday, June 26
- Half the Moon will be covered at mid-eclipse
- Easy to see; you don’t need a telescope
Australian stargazers will be treated to a partial lunar eclipse on Saturday, June 26.
All of Australia will see it, weather permitting (although in WA the eclipse will already be underway by the time the Moon rises over the eastern horizon).
An eclipse of the Moon happens when the Sun, Earth and Moon line up, with the Earth in the middle, and the Earth’s shadow is cast onto the Moon.
If the Moon goes right through the middle of Earth’s shadow, there is a total eclipse.
If it “cuts the corner” of the shadow, there is a partial eclipse, which is what we’ll get on Saturday.
The main eclipse action will be from 8:17pm to 11:00pm, Australian eastern standard time (AEST). (Do the usual time adjustments if you live in a different time zone.)
Lunar eclipses are perfectly safe to watch (unlike solar eclipses), but they happen quite slowly. The best bet is to go outside and check on it every 15-20 minutes. And you don’t need a telescope to view, just use your unaided eyes.
Generally, there are two lunar eclipses and two solar eclipses each year, but they’re not always visible from the same places each time. For any particular location, there is usually one lunar eclipse each year, with a solar eclipse every 2-3 years.
What will we see on Saturday night?
There are two parts to Earth’s shadow: a not-so-dark outer part (the penumbra), and a darker inner part (the umbra).
The Moon will start going into the penumbra at 6:55pm AEST, but it won’t be very noticeable.
It will enter the umbra around 8:17pm AEST, by which time a small, dark “bite” will seem to have been taken out of it. Mid-eclipse will occur at 9:38pm AEST, with about half the Moon’s diameter in shadow. Then the stages will work in reverse, with the Moon leaving the darker part of the shadow at 11:00pm AEST.
Australian stargazers will just catch the end of a total lunar eclipse in December this year, and the end of another one in June 2011.
There’ll be a solar eclipse in July this year, but Australians won’t see it. However, we’ll get a full view of the total lunar eclipse in December 2011.
The next big total solar eclipse visible from Australia will be seen from Cape York in November 2012.