Robertstown, SA: Is that a UFO? Astonishing moment mysterious flickering lights appear in the sky

Astonishing footage has emerged of a possible UFO sighting after flickering coloured lights were spotted in the sky north of Adelaide.

A woman posted the video, which was filmed in Robertstown in South Australia's mid north region at 8.45pm on Saturday, to an Adelaide UFO sightings Facebook page.

'We were watching two lights move up down left right,' the woman's friend commented on the post.

'(The lights) shine very bright then just disappear, only to reappear again.

'This was happening just left of and below the moon.'

The video captured a series of coloured lights flickering in the sky.

'We're not too sure what it could be,' a woman can be heard in the background.

'It's just really bizarre.'

Aussies were stunned by the pair's experience and their footage. 

'Freaky AF,' one wrote.

Others claimed they spotted similar sightings in other parts of South Australia. 

'I saw similar at Semaphore Beach,' another said. 

Another wrote: 'I saw something today. It wasn't lights it was during early arvo just an object hovering way to high to be a drone it was moving a bit then stopping kept fading in and out.'

A third commented: 'I saw a similar thing about six months ago in the hills. Three coloured lights in a line moving steadily downwards. Didn't have my phone on me.'

But not all Aussies were convinced the footage showed a UFO and believed there was a simple explanation.

'Drones usually have that coloured lighting,' one wrote.

Another added: 'I feel pretty definite that they are drones with those coloured flickering lights.'

A third wrote: 'Someone playing with drones maybe!'

But a drone pilot pointed out that drones are rarely up that high. 

'I'm a high altitude drone pilot, (hobby only ) it just amazes me with all these pretty lights I never catch anything when I'm up,' one wrote.

'And about at 5km looking around, I can assure there is bugger all - in fact NO other drones around any part of the day or night, NOTAM can confirm this.'

The footage comes after a spate of UFO sightings in South Australia over the last decade.

South Australia's Astronomical Society's Paul Curnow previously told ABC News that UFO sightings are fairly common.

'The average city person doesn't look at the sky very often and sometimes when they do look up and see something strange, they can't really explain it,' he said.