by Chris Tobin
A suspected meteor which flew over Christchurch and caused a sonic boom in North Canterbury last week did not surprise Geraldine’s Peter Aldous.
He and a fellow West Melton amateur astronomer, Ian Crumpton, are monitoring and photographing the skies every night for meteors.
“Meteorites are happening all the time. The nearest we’ve had that have hit the ground are at Mt Hutt and Lake Coleridge,” Mr Aldous (78) said.
“Since we’ve been doing it, we’ve photographed 24,000 meteor orbits up to the end of 2016 and the number is still growing. There have been 44 new meteor showers discovered and that number should grow also.
“We are now monitoring for brief meteor shower outbursts – showers that last only a few hours which are caused by comets that could potentially hit us.
“The idea is that if we find such a shower, we can have the comet searchers look deeper into space along that orbit to see if they can find it before it comes near the earth.
“The southern hemisphere is almost all ours; we have Mount John Observatory doing the scientific work with Canterbury University.”
Both Mr Aldous and Mr Crumpton have the task of collecting data for the scientists.
Each has 16 cameras at home to scan the skies each night. The cameras were brought to the country by the Carl Sagan Institute of Cornell University in the United States, which is working in conjunction with the University of Canterbury.
The institute was founded four years ago to search for habitable planets and moons in and outside the solar system.
“What we’ve photographed is downloaded to the universities. They’re taking five to six hours of our photos a night.
“Their job is to sift through all this. They study the data, searching for meteorites and any new meteor showers and try to determine what asteroid or comet created it.
“Comets going around the sun lose debris and the debris creates meteor showers.”
Since New Zealand was a narrow country few meteors struck ground here, most landing in the sea, Mr Aldous said.
“The one that went over Christchurch is reckoned to be the size of a fist.
“It was photographed by a lot of people. You could see its trail but we don’t know if it landed in the sea or on ground.
“I’ve also seen them in the daytime – bright white light.
“Most meteorites are small, thank God!”
The largest meteorite recorded in recent times occurred in February 2013. Measuring 20 metres in diameter and weighing 12,000 metric tons, it exploded over Chelyabinsk in Russia, causing widespread damage to buildings but no-one died.
Mr Aldous has his own high-powered telescopes and the public can visit his observatory to view the skies through them.