Wow - todays Space Weather front page, is also asking the question. They seem to be saying maybe it was'nt a rocket burn??
http://spaceweather.com/
MYSTERY BURN: Last night at the Siding Springs Observatory in New South Wales, Australia, astrophotographer Gordon Garradd witnessed a glowing cloud in the sky. "It looked like a rocket burn." He took this picture at 17:30 UT on Feb. 19th:
http://spaceweather.com/swpod2007/20...add1_strip.jpg
Photo details: Nikon D200, 85mm lens @ f/1.6, ISO 500, 4 sec exposure.
"I've seen rocket burns before and there is no doubt the cloud is rocket exhaust," says Garradd. "However, this is much larger than any I have seen before, such as Cassini. It makes me wonder if I saw a controlled burn or an explosion."
The cloud contained a swarm of small objects. To display their motions, Garradd is assembling a movie from his photos. The movie will also show the cloud drifting slowly across the sky. "It was visible for nearly an hour," he says. The burning question: If this was a rocket burn, what rocket was it? Ideas welcomed! UPDATE: Others photographed the same cloud. "I was lucky enough to be shooting the exact part of sky that this object appeared in," reports Ray Palmer of the Golden Grove Observatory in Chittering, Australia. "I have no idea what it was, but it grew in size and moved quickly. I managed to view it for 35 minutes: image." Yet another photo of the cloud comes from Tim Thorpe at the Bull Creek Ranges in Meadows, South Australia. "Quite a surreal scene," he says.