Sydney’s skies have delivered no shortage of light shows recently, from Vivid’s illuminated landmarks to a string of lunar and astronomical events, including the stunning aurora australis. And there’s another reason to look up this weekend. A rare blue micromoon will rise above Australia on Sunday night, combining two unusual lunar phenomena in a single event. Despite its name, the moon won’t actually appear blue, nor will it look dramatically smaller than normal. Instead, the event brings together two relatively uncommon lunar occurrences that don’t often coincide, making it a noteworthy sight for skywatchers. Here’s everything you need to know.
What is a blue micromoon?
A calendar blue moon occurs when a single month features two full moons — this Sunday marks the second one for May. The ‘micro’ label refers to distance. Because the moon travels on an oval path rather than a perfect circle, it has points where it drifts furthest from Earth, known as an apogee. When a full moon hits this far point, sitting roughly 406,000 kilometres away, it is technically a micromoon.
While it sits further away, your eyes won’t actually notice a tiny sphere in the sky. It is only about 6 per cent smaller than an average full moon. In fact, when it first rises above the horizon, a visual effect known as the moon illusion can make it appear larger than it actually is.
When to see the blue micromoon in NSW
Skywatchers across New South Wales will be able to see the blue micromoon on Sunday, May 31, with the moon reaching peak fullness at 6.45pm AEST. Fortunately, you won’t need to pull an all-nighter or time your viewing perfectly, as the moon will appear full throughout the evening and remain visible for most of the night.
The best time to look up is shortly after moonrise, when the full moon emerges above the horizon and begins its journey across the sky. This is also when it tends to appear at its most dramatic, often taking on golden, orange or reddish hues as its light passes through more of Earth’s atmosphere.
How to get the best views in Sydney
You won’t need any special gear or telescopes to see the show (if skies remain clear) but a few quick adjustments will definitely upgrade the experience. The moon will rise in the southeast before charting a low path across the southern sky. To get the clearest view, head somewhere with an unobstructed look at the southern horizon — think coastal headlands, national parks and open parklands. In Sydney, locations such as the Bondi to Coogee coastline, Observatory Hill, Barangaroo Reserve and the Southern Hemisphere’s first-ever urban night sky place offer unobstructed views of the night sky.
Read more about the blue micromoon on the NASA website.
