Lee Hawkins was visiting a friend at Legana when he noticed a group of about 20 small orange lights floating across the sky.

''They came over in patches at about plane height and seemed part of a synchronised group,'' Mr Hawkins said.

Martin George, of the Queen Victoria Museum and Art Gallery's planetarium, said there was nothing in the atmosphere that night to explain the lights and attributed the sight to either flares or candle lanterns.

Candle lanterns, also known as Chinese lanterns, involve a paper lantern or bag attached to a candle. They have been known to reach heights of 1500 metres and travel up to 20 kilometres.

''I have a strong suspicion that what we have here is something being sent up in to the sky, there is definitely nothing astronomical that would behave in that way,'' Mr George said.

Phil Polden, of the Tasmanian UFO Investigation Centre, said he would not like to speculate but agreed the lights resembled those of chinese lanterns.