Victorian stargazers have been treated to a spectacular blue supermoon this week for the second time in less than two years.
But if you missed the celestial phenomenon over the last three days, unfortunately you’ll have to wait another two years to see it again.
The rare blue supermoon was captured by Kevin Troy in Melbourne’s Caulfield North. Credit: Kevin Troy
Meteorologist Michael Efron, from the Bureau of Meteorology, said Melbourne would most likely see its next blue supermoon in 2026.
“We had a blue supermoon in August last year, and we’ve had another one this year, so Melbourne will have to be patient for the next one,” he explained.
The most recent supermoon appeared from Sunday morning through to early Wednesday morning, delighting Melburnian photographers and lunar enthusiasts.
Efron said minimal cloud coverage and rainfall made Monday evening perfect for supermoon viewing.
The supermoon (seen here in a photo taken from Moonee Ponds) is not necessarily blue to the naked eye.Credit: Arun Chandran
“The best conditions for a supermoon require high-pressure systems and as little cloud coverage as possible,” he said.
Professor of Astrophysics at Macquarie University Richard de Grijs said the supermoon appeared at dusk on Monday and peaked on Tuesday morning at 4.30am.
“The moon’s orbit around Earth is not quite circular, so there is a single point where it is closest and furthest away,” he said. “A supermoon occurs when a full or new moon is within 90 per cent of its closest approach, which makes it look bigger and brighter in the sky.
“On Monday at dusk, the moon was fairly low above the horizon, so it would have seemed even bigger to onlookers.”
While the colloquial phase ‘once in a blue moon’ means something is rare, the actual event is fairly regular and occurs every two to three years. When two full moons rise during the same calendar month, the second is known as the blue moon.
The term may be slightly misleading, as the moon itself does not drastically change colour. In fact, said de Grijs, it’s more likely to adopt a blood-red or yellow shade: “Red light bends and refracts more than blue light, so the moon appears red when it’s closer to the horizon.”
Social media sites including the Aurora Australis and Astrophotography Facebook pages were overwhelmed with supermoon images, with avid photographers posting photos from inner-city Melbourne to country Victoria.
Keen photographer Kevin Troy ventured into his Caulfield North backyard with camera on Monday night to capture his “close celestial neighbour”.
“ I don’t think people realised how incredibly detailed the moon is, with all of its craters,” Troy said. “It was just such a spectacular night and experience.”
Victorians were last treated to a blue supermoon in August 2023, the first time since 2009. Does this mean the celestial phenomenon is becoming less rare? De Grijs doesn’t think so.
“Normally, blue supermoons happen every two to three years, so it’s fairly uncommon to have another so soon,” he said.
“But months and seasons are human concepts. The moon just goes around its orbit and happens to coincide with calendar months and seasons.”
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