A flood of UFO sightings over Australia was probably prompted by the launch of the Falcon 9 private spaceship.
According to local news reports, a spiral lightshow appeared in the early-morning sky over New South Wales, Queensland and the Australia Capital Territory.
"It had a distinct bright centre, much like a bright star, indicating an object shedding light trails, spiraling and fattening out from it," one witness told ABC.
It was described as yellowish, and lasted two or three minutes.
But according to Nick Lomb of the Sydney Observatory, the lightshow was probably the Falcon 9 spaceship, which blasted off on Friday. The second stage booster of the rocket would have been spinning, releasing water vapour as it did so to create the spiral effect.
"Circumstances were perfect for the visibility of the spacecraft over eastern Australia. The craft had been launched at 4:45am AEST from Cape Canaveral and had reached orbit within nine minutes," says Lomb.
"An hour later, after travelling across a large part of the globe from west to east (the same direction that the Earth turns on its axis) it reached the east coast just before nautical twilight that occurred in Sydney at 5:55am. The timing meant that the rocket, circling about 250 km above the ground, was illuminated by the sun while the sky was still dark."
Watch the spiral light on YouTube, here.