As the moon rose over Sydney on Monday night, it was at its closest point to earth since 1948.

But for some, it didn't live up to expectations.

The proximity produced what's known as a "supermoon", with the moon appearing larger and "significantly brighter" in the sky just after 7pm - for those lucky enough to see it.

According to NASA, the moon was up to 14 per cent bigger and 30 per cent brighter than usual.

The moon appeared larger near the horizon as it was around 30,000 kilometres closer to earth - a handy 356,509 kilometres away.

Heavy cloud cover blanketing the city left many disappointed, as hundreds gathered on beaches including Bronte Beach hoping to catch a glimpse of the rare lunar event.

As the sun set and patches of blue sky began to appear, dozens of people stood next to Sydney Observatory in Millers Point.

Tourists and locals looked north-east towards the Harbour Bridge, waiting for a sign of light in the grey. Several came equipped with professional-looking cameras, while others chatted and lounged on the grass.

A group of police officers arrived close to dusk and watched the scene closely. The crowd milled about casually, until just after 7.30pm when someone exclaimed: "Over there!"

Half those gathered surged to the southern end of the park just in time to see a sliver of the moon as it appeared in the space between two clouds, then swiftly climbed back behind cloud cover.

Eight minutes later, it began to peek out again. "I see it! Right there!" one man said, and once again all eyes trained east, cameras and smart phones whirring to life.

Spanish tourist Laser Acosta took photographs with his camera, mounted on a tripod, while another man stood silently, streaming the scene on live video app Periscope.

Finally, at around 7.45pm, the moon rose out of sight, behind cloud once more.

Mr Acosta said it was "amazing" to see the supermoon while he was visiting Australia.

"It was a bit cloudy, actually, but I got some good pictures," he said, scrolling through the high-definition snaps.

"I've been on a road trip from Darwin. This is the first time I've taken photos of the moon."

On a nearby picnic blanket sat Aditi and Justin, who had travelled from the city's west to catch a glimpse.

"We didn't get to see much of it," Justin said.

Aditi added: "I feel like we weren't in the ideal place, but it was good."

Residents of Brisbane and Perth were forecast to have clear skies for the celestial spectacle.

Professor Fred Watson from the Australian Astronomical Observatory told Nine News the event was "essentially... the brightest full moon since 1948".

Meteorologists tipped the best view would be looking to the east at sunset, where some of the moon may have been able to peek through thick cloud cover.

The next time the moon will be so close is in November 2034 - but there may be a silver lining for amateur astronomers who missed out on Monday.

Ben Domensino, a meteorologist with Fairfax Media's Weatherzone, said the moon will appear "just as large to the naked eye" on Tuesday.

The moon's distance from Earth varies because it is in an egg-shaped, not circular, orbit around the planet.

with Reuters