A barrage of mysterious burning space debris over the New South Wales south coast was a sign of more danger to come, according to a space junk expert.
A celestial sound and light show complete with flares, explosions and a sonic boom lit skies across parts of south-east Australia for two hours on Tuesday night.
Police said they received a substantial number of reports about the strange lights and loud bangs, which were described as more powerful than fireworks or thunder.
Scientists said the light show was caused by either a meteor or space junk burning up as it entered the earth's atmosphere. No debris was found.
Batemans Bay's Bay Post newspaper editor Chris Graham said he heard what sounded like an explosion, and which he could only describe as a sonic boom, triggered when an object breaks the sound barrier.
"I still haven't heard (another) credible explanation for it," he told AAP.
Australia Institute Director Clive Hamilton said the rapidly increasing amount of space junk left in space made random and dangerous collisions with earth increasingly likely.
"There are over a million pieces of space junk orbiting the earth, and some of them are going to come crashing to earth sooner or later," he told AAP.
"There's certainly a lot of alarm about it in space circles. They now have to put extra armour plating on satellites and space stations and so on because of collisions with space junk.
"It's also alarming when you see these events which could be meteor showers, could be space junk reentering the atmosphere, could be the Mir Space Station.
"No one really knows, or at least they're not saying - we really are kept in the dark when there's some particular threat."
The space show came a month before Russia begins its controlled dumping of the troubled Mir Space Station over the Pacific Ocean, off the east coast of Australia.
Experts have warned that plan could easily go wrong, after a 1979 deorbiting scattered the US Skylab over Western Australia instead of the South Atlantic as planned.
Some scientists said the meteorite would have been the size of a coffee cup, others said it was as big as a fridge, while another said the earth may have passed through a comet's tail.
They disagreed about the possibility a series of grass fires around Canberra and Batemans Bay were started by flying embers, a theory played down but not ruled out by emergency services.
UFO Research Centre Director Diane Harrison said a burning the ember could easily start a fire in dry scrub, before burying itself in sand so it could not be traced.
"Space junk" sighted over Calwell was believed to have sparked a grass fire beside the Monaro Highway, an ACT Fire Brigade spokesman said.
The fire, near the intersection with Isabella Drive, was quickly contained by six fire-brigade units, but speculation about the cause ran rife through the ACT emergency services.
"An eyewitness at the Calwell shops said she saw a piece of something silver crashing into the ground," an ambulance spokesman said.
ACT police confirmed that a flare had been seen falling from the sky near the Monaro Highway, and said they had received similar reports of floating space junk from the South Coast.
Batemans Bay police were also fielding calls last night about sonic booms, flares, and "big comets in the sky", but no damage was reported and no objects were found, a spokesman said.
A total fire ban in the ACT had been extended until midnight tonight, ACT Emergency Services said yesterday.
Householders have been warned that gas and electric barbecues may be used but that wood, charcoal and spirit-burning appliances are banned.
Oz Mystery: Sonic Booms, Silver Flying Objects
AAP -- [Original headline: Space debris ominous sign: expert]
NineMSN News / Australia - December 27 2000
[Original headline: Speculation 'space junk' caused fire]
Unexplained reports of sonic booms, flying silver objects and flares seen falling from the sky were made to emergency services throughout the ACT and South Coast last night [December 26].
The Canberra Times / Australia | By Stacey Lucas - December 27 2000
