The longest partial lunar eclipse visible in New Zealand in more than 800 years should provide a stunning spectacle tonight, the Otago Museum director says.
It is called a blood Moon because during a lunar eclipse the Earth passes directly between the Moon and the Sun so the Earth's shadow falls directly on the Moon, an expert says. (file pic) Photo: Pixabay
It has not been seen in our skies since Kupe landed in Aotearoa 800 years ago. It starts at around 8.20pm although the best time to see will it be just after 10pm, Dr Ian Griffin told First Up.
"You'll see a dark shadow starting to eat away at the bottom part of the Moon and over the next hour and a half, as the Moon gets higher in the sky, the shadow will climb across more and more of the Moon until just after 10 o'clock 97 percent of the Moon is going to be covered by the Earth's shadow and it should be blood-red in colour and low in the north-eastern sky and it should be a marvellous, marvellous sight because not only will it be blood-red and much dimmer than the normal Moon but you'll see the sub-cluster Matariki so it should be very pretty indeed."
People in the north of Aotearoa see the Moon rise earlier so will see more of the eclipse, however, it will still be visible around the rest of the motu.
"The interesting thing about this is that it's a very very long eclipse and the reason for that is that the Moon is at its furthest part of its orbit away from the Earth; it's called a micro Moon tonight ... because it's so far away from the Earth it moves very slowly and that's why the eclipse is so long."
"You'll see a dark shadow starting to eat away at the bottom part of the Moon" Otago Museum director Dr Ian Griffin
It is called a blood Moon because during a lunar eclipse the Earth passes directly between the Moon and the Sun so the Earth's shadow falls directly on the Moon and that is why it gets dark, Dr Griffin said.
"At the mid-phase of the eclipse the only light falling on the Moon is from all of the sunsets around the Earth so that is why the colour goes red. It's a very beautiful thing."
While lunar eclipses happen every couple of years, the next one as long as tonight's will not occur for another 648 years' time in 2669, he said.
Carolle Varughese who is a councillor at the Auckland Astronomical Society also expects the blood-red phase of the eclipse will be able to be observed all over New Zealand.
"The Earth and the Sun and the Moon all line up" Carolle Varughese, Auckland Astronomical Society
"This is a full Moon and the Earth and the Sun and the Moon all line up so the Earth is sort of in the way of us getting a good full Moon and it's sort of just blocking the light from the Sun a bit, giving us the blood Moon."
The eclipse last May involved a super Moon and while most people can't see much difference between a micro and super Moon astronomers and enthusiasts will get "pretty excited", she said.