Australians are set to witness a rare lunar event this Sunday night, known as a blue micromoon, which combines two separate astronomical phenomena: a blue moon and a micromoon.Despite its name, the moon will not appear blue.A blue moon refers to the second full moon occurring within a single calendar month, and in this case, it follows another full moon earlier in May.The term is relatively modern, with definitions only becoming widely used in the past century.

The second aspect of the event, the micromoon, occurs when a full moon coincides with the point in its orbit where it is farthest from Earth, known as apogee.As a result, the moon appears slightly smaller and dimmer than usual, although the difference is subtle.

Astronomers estimate that this micromoon will be around 6 per cent smaller than an average full moon, a variation that is not typically noticeable to the human eye.According to astronomers, the moon will still appear bright and prominent in the night sky, described as being extremely luminous compared to stars.Experts note that it can be seen easily across Australia, provided the sky is clear and there is minimal light pollution.The best viewing time is expected to be around 6:45 pm on Sunday 31 May, when the moon reaches its peak fullness.However, it will remain visible throughout the evening and night.No special equipment is required, and observers are encouraged to find a dark, open area for the clearest view.The event is considered rare due to the coincidence of both a blue moon and a micromoon occurring simultaneously.