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Once in a red moon: a beautiful lunar eclipse
August 30, 2007
Time lapse images of the eclipse. Photo: Mike Gal Time lapse images of the eclipse. Photo: Mike Gal

UNSW space scientists joined millions of people across the nation who enjoyed perfect conditions for viewing the first total lunar eclipse since 2000.

On the mild Autumn evening of August 28, star-gazers looking to the heavens saw the earth's shadow crossing the moon at 6:51pm (AEST) and completely cover the moon by 8:40pm, turning it red.

Despite fears that cloud cover might obscure this uncommon celestial sight, the spectacular eclipse was clearly visible without a telescope.

"A lunar eclipse is one of those rare events when the earth passes directly between the moon and the sun," says UNSW space scientist Michael Burton who witnessed the event from his backyard in Sydney's eastern suburbs.

Dr Burton notes that an eclipse happens when "the moon falls into the earth's shadow and disappears from view for a couple of hours as it passes through that shadow."

"Despite being in shadow the moon is illuminated by a small amount of light from the sun being bent around the earth's atmosphere," he says.

"This is the result of refraction, the same phenomenon that causes a stick in water to appear bent", Dr Burton says.

"The refracted light bounces back of the Moon's surface, passing through the Earth's atmosphere a second time.

"This is what makes the Moon's surface appear a ghostly reddish colour, as all the shorter wavelength blue light has been scattered away by its long passage through our atmosphere, leaving just the longer wavelength red light."

School of Physics colleague Dr Michael Gal captured also witnessed the eclipse from his Sydney home.

Describing the eclipse as "amazing" and "beautiful" Dr Gal, a UNSW physicist photographed several images of the lunar event.

"I set up my camera in the garden and took a photo every 15 minutes or so. I live near the Royal National Park where there is very little light pollution. With such perfect viewing conditions the moon appeared in the sky like a big red ping-pong ball."

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