For amateur and professional skygazers alike, this weekend is set to deliver a new year's gift – as long as the weather comes to the party.

"There's a lot of beautiful stuff up there in the night sky," said Sydney Observatory astronomer Geoff Wyatt. "We all know the hit-parade things – the moon, the stars and the planets. But every now and then you get something out of left field and it's like a surprise birthday present."

Terry Lovejoy, who discovered comet Lovejoy that survived a death dive

The gift on offer to astronomy enthusiasts is the Lovejoy comet, which will enter its brightest phase over the weekend.

The comet is expected to be bright enough for backyard astronomers and professional sky-gazers alike to see its greenish glow with the naked eye.