KEY POINTS:
Clouds blowing across the sky in high winds over Auckland last night failed to prevent a spectacular sight for stargazers.
Unsettled weather had been forecast for the total lunar eclipse, starting around 8.50pm, when the moon was gradually shielded from the sun by the earth.
The forecast was
correct but there were enough breaks in the cloud to witness the rare event.
Alan Gilmore, a senior astronomer at the Mt John Observatory at Lake Tekapo in the South Island, said last night that "extremely overcast" skies when the eclipse began about 7.50pm cleared rapidly.
"The skies cleared dramatically about 9pm, and we've had good views since. We've been debating the colour and decided it's perhaps a dried apricot."
Mr Gilmore said during the last lunar eclipse in 2000, the moon looked like it was "red-hot", while tonight's moon was a much duller colour.
A spokesman for Dunedin Astronomical Society said a deluge around 5pm had cleared and although viewing had been patchy since, there had been plenty of chances to chart the eclipse's progress.
"We're getting a great view at the moment - the moon's been ducking out between the odd shower," he said last night.
"It's quite a bright red, and you can see quite a bit of detail on the moon's smooth surfaces."
In Wanganui, a spokesman for the Wanganui Astronomical Scoiety said viewing had been intermittent.
"Right at the moment we're struggling with patchy cloud - we watched the moon disappear into the shadow, but now we're just getting the occasional glimpse.
"It's quite interesting when you do see it, it's gone quite red."
Although it was a total eclipse, the ring of light around the earth's edge is enough to illuminate the moon's surface, said Graham Murray, Stardome Observatory's education and programmes manager.
If there is enough dust in the earth's atmosphere the surface will appear blood red, as was the case tonight.
An eclipse occurs when the earth passes between the sun and the moon, blocking the sun's light. It is rare because the moon is usually either above or below the plane of the earth's orbit.
The lunar eclipse started at around 8.50pm, turning red from 9.50pm onwards. It was completely red at 10pm for an hour, and the eclipse finished at around 12.25am.
The last time a total lunar eclipse was visible over New Zealand was in July 2000, and the next occurrence observable from New Zealand is on December 21, 2010.
Sessions at Stardome have been fully booked. The observatory is also beaming live feeds of the event from Sydney and Hawaii in anticipation of foul weather.
Professor Mike Dopita from the Australian National University's School of Astronomy said: "The moon gets this sometimes quite blood red colour and it's quite an interesting sight to see, although it is of no astronomical importance at all."
Professor Dopita said it was hard to predict exactly what colour the moon would be. "It really varies. Sometimes it's a kind of a sunset yellowish colour, sometimes it looks quite red. It depends upon whether there's been volcanic activity.
"When there's more dust it turns redder. After Mt Pinatubo Volcano (in the Philippines) erupted (in 1991) there was lots and lots of dust in the atmosphere but that has all settled."
- AAP, NZ HERALD STAFF, NZPA
