New Zealand's super blood moon: Weather forecast, how to see it

Forecasters say conditions are looking good for spotting the super blood moon on Wednesday night.

The exciting astronomical event will see a large rusty-blood-red moon hanging in the sky. The last time it happened over New Zealand was 40 years ago - in December 1982.

But if you want to see it you'll have to be quick.

What is it?

A super blood moon is a rare combination of three factors: a full moon, a super moon and a total lunar eclipse.

A super moon is when a full moon phase coincides with the moon's closest approach to Earth.

"A super moon, which happens at perigee, will appear 14 percent bigger and 30 percent brighter than its opposite, a micro moon," Stardome Observatory and Planetarium astronomy educator John Rowe explains.

A blood moon is when Earth lines up between the moon and the sun, hiding the moon from the sun and blocking most of the blue light. The remaining heavily filtered light refracts onto the moon's surface, causing a red glow.

A blood moon rises.
A blood moon rises. Photo credit: Getty Images

How to see it?

The spectacle will happen on the night of Wednesday May 26. But it won't last long - just 14 minutes.

"Between 11:11 and 11:25pm on Wednesday the moon will appear rusty red in colour and larger than usual," NIWA says.

NIWA forecasters say New Zealanders can expect clear skies to see the event. Based on its models, the best places to view the super blood moon are: Southland, Otago, West Coast, Canterbury, Tasman, Nelson, Marlborough, Wellington, Manawatu-Whanganui, Taranaki, Waikato and Auckland.

Meteorologist Ben Noll says there is some scattered cloud forecast for Fiordland, Northland, and Bay of Plenty, but stargazers shouldn't be discouraged because there may be enough breaks in the cloud to spot the moon.

Hawke's Bay and Gisborne have a reduced chance of spotting it because of thicker cloud cover.