* Astronomy

So was it a meteorite or space junk falling to earth? No one knows. But at 1.30pm in the afternoon of July 19, many people across the Mid North of South Australia - from Wirrabara Forest to Quorn and Hawker saw a large object moving across the sky.
One witness, John Teague was at Hawker in the Flinders Ranges. He was pumping tyres when something caught his eye.

"I thought it was a flare. It was the colour of mercury and had a tail and there were sparks coming from it. Then it seemed to break up and disintegrate." He said it was large, not as large as a full moon, "more like a cricket ball".

About four minutes after it disappeared, John heard a "sonic boom". He said, "It was really loud, like thunder".

The seismographs at Hawker and Wilpena registered the boom as a disturbance. David Love, seismologist with the Department of Primary Industries and Resources in Adelaide confirmed that equipment "at Hawker and Wilpena recorded the same thing".

"What we've recorded is a soundwave coming somewhere south of Hawker, whether it's south west or south east is a bit hard to tell."

He said they haven't got enough case studies to compare this sound with a sonic boom from a jet. And this is complicated further because the disturbance detection instruments are in the ground.
So will property owners in the area during the weeks and months ahead find space junk or meteorite fragments? From what the seismographs indicated, David Love concluded, "If anything did hit the ground, it wasn't large".

So what was it? The United States Space Command in Colorado said "there was no scheduled re-entry of any spacecraft or satellite."
The CSIRO, the Civil Aviation Authority and the Australian Airforce at the Keswick Barracks, all said they knew nothing about it.
The Astronomical Society in South Australia is keen to hear from any witnesses so they can determine what it may have been.

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