And the truth is .........

Massive sonic boom from meteor
12 September 2006

A massive sonic boom rent the skies above Canterbury today as a meteor sped to its fiery end ? but if, and where, it fell remains a mystery. Scientists said the boom was heard as far afield as Wellington, and sightings of a bright speeding light, then cloud of smoke as the meteor apparently burst into a fireball, were reported all over Christchurch.

One astronomer said it was likely the meteor completely disintegrated when it burst into flames, and debris from the alien visitor was unlikely to be found. The meteor was detected by instruments used to measure earthquakes at two Canterbury recording sites.

Kevin Graham was working in his garage workshop in Rolleston, 22km southwest of Christchurch, when he heard the boom. His first thought was it was a September 11 anniversary attack, he said. "I don't frighten very easily but I was just about shitting myself," he said.

He spoke by phone to his wife in the Christchurch suburb of Addington who had run outside because she thought the Addington Raceway stand was going to collapse. "I ran outside because I thought my place was going to collapse as well," Mr Graham said.

He said the sound shook the garage and he could feel shock waves in the air. "It started off with a little boom then a real massive boom. And I mean massive ? like the daddy of all booms," he said. "I was wondering what happened and I thought `oh, September 12', because we're a day ahead of the States.

Emergency services were inundated with calls from the public about the noise. Christchurch Fire Communications received its first calls from the public started at 2.53pm today, with people reporting windows rattling and the air "shaking". Police communications fielded over 100 calls in quick time.

Hanmer Springs police officer Senior Constable Chris Hughey likened the meteor to Haley's Comet, which he saw when it last passed near Earth in 1986. "All it looked like was a vapour trail from a plane coming in at huge altitude," he said. "It was a crystal clear day here in Hanmer and it appeared to have a red ball or something at the front. Then it split into about three and just disappeared."

Mr Hughey said he did not hear the loud sonic boom. He had seen a few small meteors "coming in here and there" over the years but nothing like today's one. "Never coming in on that angle. "It just disintegrated at great altitude. It was moving, too. I don't know what speed they come in at, but it was going."

Resident superintendent of the University of Canterbury Mt John Observatory Alan Gilmore said the reports seemed to confirm the meteor burst into a "terminal fireball" while travelling over Canterbury, possibly as low as 60km above the ground.

The meteor would have broken through the atmosphere at a rate of between 10 and 20 kilometres per second. The thicker air closer to earth could have slowed it down to about 40,000kph, and it was this rapid deceleration that would have caused it to break, Mr Gilmore said. "The stress on the rock is so intense, that it just goes flash and breaks up into a ball of smoke or fire."

A couple of sightings had put the meteor landing in fields but Mr Gilmore said these seemed to have been discounted. He could only make a "wild guess" at what size the meteor had been, but said he would be very surprised if it had been larger than a basketball.

It was an exciting, if not totally unusual event. Nine meteorites had been recovered in New Zealand ? the most recent being a four billion-year-old 1.3 kg rock which hit the home of Phil and Brenda Archer in Auckland on June 12, 2004.

The rock travelled up to 700 million kilometres from the asteroid belt between Mars and Jupiter before punching through the couple's roof.