Stargazers say a meteor that floated across Adelaide skies overnight looked like a flaming tennis ball before it disappeared from view.

The object appeared in the sky about 9:30pm, with people from around Birdwood, Norwood, Mannum and Balhannah reporting sightings to ABC Local Radio.

One listener, Barry from Murbko on the River Murray, said he was watching television when he saw the object through his window.

"I saw this ball of flame, it would have been about the size of the moon just above the tree tops," he said.

"It was a flaming ball and it went across the the tree tops at a very low altitude and it wasn't travelling that fast like a shooting star.

"This just took my breath away. It was that incredible I just sat there for ten minutes and couldn't believe what I just saw.

"This was just like a ball of flame, like somebody lit up a tennis ball and hit it with a tennis racquet."

Paul Curnow from the University of South Australia's Adelaide Planetarium said the object was probably a meteoroid that ignited as it entered the atmosphere.

"We have these pieces of rock, the small ones we call meteoroids, the really large ones we refer to as asteroids in the case of the one in Russia for example," he said.

"When it's floating in space we call it a meteoroid. When it comes into the atmosphere and we see it we call it a meteor. When it actually hits the ground we call it a meteorite.

"These fragments of rock fall into the earth's atmosphere and as they fall into the atmosphere they form a pressure wave in front of the falling object which heats up the rock and we see that as a fireball or a shooting star.

"There are about 19,000 objects from space [that] come in every day and hit the Earth's atmosphere.

"The case in Russia just recently, that fell over a populated area and in 1908 in Tunguska in Russia there was a fairly large hunk of rock come in and it actually did a similar thing.

"It airburst over a forest and it blackened about 2000 square kilometres of forest. If that had gone off over a large city, the casualty rate would have been extremely high."