Stardome astronomer Josh Aoraki told RNZ a blood moon, or lunar eclipse, is when the moon passes through the earth's shadow, called the umbrella, creating a "red hue" - hence the name.
Aoraki said the eclipse would reach totality between 8pm and 8:30pm Friday.
He said it would be able to be seen with the naked eye, but if you had a camera, telescope or binoculars it would be worth bringing those along.
The moon will rise in the east after sunset, so Aoraki's advice to see the moon is to look towards the eastern horizon, or head to a beach on the east coast.
However, weather would play the biggest factor in whether you can see the blood moon.
Luckily, MetService is forecasting a "mainly fine" Friday for most of the country, with isolated showers about Bay of Plenty and Coromandel.
In the South Island, the West Coast is forecast to experience a few showers, turning to rain in Fiordland, and isolated showers in Otago and Southland, clearing later on.
The last blood moon occurred in 2022; however, this year there will be two blood moons, so if you miss tomorrow's lunar eclipse, you'll get another chance later this year.
