SPACE junk, meteor showers, iridium flares... or just a wedding lantern let off down at the beach - there have been plenty of suggestions about what the strange lights over Tannum Sands on Saturday night could have been.
One reader suggested the lights were the sun's reflection off iridium communications satellites.
"On a really dark night they can seem larger than they actually are and even quite spooky. If the angle is right and there is more than one satellite, people could potentially see more than one flare from different satellites while looking in the same general direction," he said.
"The flaring causes a momentary brightening and then dimming of the normal reflected light. I see these occasionally on my evening walks when it starts to get dark.
"The orange colour is a bit unusual, but I have read reports of red-coloured iridium flares. I guess it all depends on dust particles in the atmosphere, angle of reflection, any high level cloud that might be present, and time of night... just as we see a red and orange sunset on clouds in the evening."
Professor Michael Drinkwater, head of the Astrophysics group at the University of Queensland's School of Mathematics and Physics, has viewed video footage of the lights and said it was nothing he had seen before.
"It's a bit hard to tell and get a feel for the size of it," he said.
"I haven't seen iridium flares before, but they wouldn't last for as long. I've seen aircraft that look like that, but the changing colour is unusual. It's a bit puzzling - it may have been seen through cloud."
Prof Drinkwater ruled out meteor showers as the cause.
"Anything like a meteor is only a few seconds. Anything coming towards earth moves faster," he said.
"There are all sorts of things that produce light in the atmosphere. It's hard to work out what they are.
"If you're not used to seeing things in the sky, it can be surprising. It's fun to start to see what's in the atmosphere."
Another reader suggested the lights were a hoax.
"Many years ago, while camping at Teewah, my friends and I made a number of hot air balloons out of plastic garbage bags, wire coat hangers and fuelled them with hexamine tablets.
"We sent them out to sea on a light offshore breeze at night. Low and behold, UFO sightings were reported in the area, with people claiming to have seen rapidly moving lights which changed colour and height randomly. I think we have something similar here."
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