Australians will have less than five minutes to see a total lunar eclipse on Easter Saturday - or face a wait of nearly three years for the next one.
The moon is due to pass through the edge of the earth's shadow late on April 4 and turn a shade of red, orange or brown.
The Sydney Observatory say totality will begin at 10.58pm (AEDT) and finish at 11.03pm, making it the briefest this century.
"It's certainly the shortest in decades," astronomer Andrew Smith told AAP.
The so-called "blood moon" should be visible across most of Australia, Mr Smith said, but will appear in slightly lighter skies earlier in the night the further west you are.
"If you're on the eastern seaboard of Australia, it will be very high in the north-east of the sky at totality," he said.
"So unless you're standing right next to a skyscraper, or unless the weather is bad, nobody should have any trouble seeing it."
The reddish colour seen during a total lunar eclipse is a reflection of light from all the sunsets and sunrises across the globe at that time.
How deep it will look depends on a number of factors, including air quality.
"What also might have a small impact is, because the moon's only skirting just inside the edge of the shadow, it might not be quite as deep an effect," Mr Smith said.
"But I don't see any reason why it wouldn't turn some sort of orangey-brown colour, it might just be a slightly-lessened effect this time."
The next total lunar eclipse visible from Australia is not expected until January 31, 2018.
WHEN TO WATCH (all times AEDT)
* 9.16pm - start of the partial eclipse
* 10.58pm - totality begins
* 11.00pm - greatest/maximum eclipse
* 11.03pm - totality ends
* 12.44am - end of partial eclipse
