Stargazers are being warned Tuesday night's blood moon is an omen in Maori tradition.
From 7.45pm, onwards people with a clear view of the moon will notice it turning red, and the night sky becoming even darker.
Society for Maori Astronomy and Research Traditions spokesperson Rangi Matamua said the phenomenon was well known in pre-European times, and for early Maori it was a time to be careful.
According to the traditional lunar calendar, Tuesday night is known as "rākau nui" - when the moon is full.
Mr Matamua said when the ancestors saw the moon turning red they would say "kua mate te marama [the moon died]".
In folklore, Rona, the woman who was captured by the moon, returns to earth for a short time seeking revenge on those who didn't save her.
The Tuhoe man said Maori believed it was an omen and people should be careful of their activities and look out for one another.