News in Science

Twilight blood red Moon for eastern Australia

Lunar eclipse A blood red Moon at twilight could be in store for Australian sky watchers tonight - weather and unimpeded views to the eastern horizon permitting.

The total lunar eclipse on 15 April is one of two for this year, and will begin before the Moon rises, says Dr Nick Lomb, consultant astronomer and curator, Powerhouse Museum and Sydney Observatory .

While the eclipse will be visible from around the Pacific rim, those in the eastern states of Australia will see it around twilight. People in central Australia will see the tail end of the eclipse, while those in Western Australia will miss out altogether.

Lomb says a twilight total lunar eclipse is quite rare.

"Just as the Sun is setting, the Moon will be rising, and it will be totally eclipsed, which should be fairly spectacular," he says.

But because the eclipse will happen so low in the sky, to see it you will need to make sure there are no trees, hills or buildings in the way.

"The essential thing is to have a really clear view towards the eastern horizon."

The Moon will already be eclipsed when it rises at 5:28 pm AEST, but at that stage the sky will still be quite bright, warns Lomb

"So it might be hard to see a slight reddish fudge on the horizon," he says.

But wait five minutes for the Sun to set and you could be in for a treat.

"It's a fair chance it will become a reasonably bright reddish Moon," says Lomb.

He says while the Moon is usually blood red, because the Earth's atmosphere refracts light from the Sun, this colour is not guaranteed.

This is because the atmosphere could make the Moon too dark to see. But, says Lomb, since there is no volcanic activity around, this is unlikely to be a problem.

By 5:46 pm AEST, the Moon will be in the middle of Earth's dark shadow and from 6:25 pm AEST it will start leaving the shadow.

Even if there are clouds, Lomb says people should still be able to see this partial eclipse, lasting until 7:33 pm AEST.

"Even if people can't see the Moon when it's red they should still be able to see the Moon creep out of the Earth's shadow and that's still interesting."

He says it is completely safe to view the lunar eclipse through the naked eye or binoculars.

On 29 April, there will be a partial solar eclipse, in which between 25-65 per cent of the Sun is covered. Southern states will have the best view of this eclipse - and, says Lomb, you'll need a good view towards the western horizon to catch this one. Unlike a lunar eclipse, partial solar eclipses require special filters to prevent permanent damage to the eye.