If you got a telescope for Christmas even better, you're in for a pretty rare treat. For the first time in almost 40 years we have a full Moon on Christmas Day. In folklore it's called the 'Cold Moon', because it occurs during the beginning of winter in the northern hemisphere.

"The last time I remember this happening was way back in 1977," said Dave Reneke, astronomy writer for Australasian Science Magazine.

"I just purchased my brand new Beta video machine, Star Wars was the big flick of the day and I was playing cassette tapes in my new car stereo. We won't see another full moon Christmas until the year 2034."

For most of Australia the full moon rises early evening Christmas night and is visible high overhead all night long. What's so special about that?

Well, it means it's a great time to check out the valleys, hills and craters, so grab that scope as we head outside for a better look.

Some of those smaller craters seen through your scope are dozens of kilometres wide and hundreds of metres deep.

The craters were formed by asteroids and comets that collided with the moon. "Roughly 300,000 craters wider than 1 kilometre are thought to be on the Moon's near side alone," Dave said.

"And you thought our closest neighbour was boring with nothing to offer!"

Let your imagination sweep you away.

Find those large grey areas and see if you can make out the face of the Man in the Moon.

Some of those grey flat plains that make up the eyes and mouth stretch over 1,500 kilometres, equal in size to the Great Sandy Desert here in Australia, and almost as vacant in interior features.

And, the moon is farther away from Earth than you think.

If the Earth were a basketball, the moon would be the size of a tennis ball 7.4 metres away.

From the moon, our Earth appears nearly four times larger than a full moon appears to us and, depending on the state of our atmosphere, shines anywhere from 45 to 100 times brighter than a full moon!

"Want to know something weird?" Dave said.

"The moon is slowly, very slowly, inching away from Earth, at a rate of about 3.8 cm a year.

"Right now the moon is more than 380,000 kilometres from Earth, but when it formed, it was just 22,000 kilometres away."