THIS scratchy CCTV footage shows the moment when the night sky above an isolated rural petrol station was pierced by blinding light as a blazing asteroid blasted through the earth's atmosphere.
Thanks to the automated camera recording, scientists were able to pinpoint the area where the ten tonne space rock finally disintegrated - on the outskirts of the tiny Canadian town of Buzzard Coulee.
Here, in Day Two of our extracts from a new book by Sun professor Brian Cox, Wonders Of The Solar System, he describes the meteorite's spectacular final moments - and tells how he was lucky enough to find a piece of it in the Canadian wilderness.
THE Canadian province of Saskatchewan is a cold, dark place in winter. But on the night of November 20, 2008, its skies were lit up by a fireball five times as bright as a full moon.
The light show witnessed that night was the result of an asteroid - a space rock weighing about ten tonnes - entering Earth's atmosphere and landing in a place call Buzzard Coulee.
It's certainly not unusual for rocks this size to hit us - on average it happens about once a month. But what was unusual about the Buzzard Coulee meteorite was that its trajectory took it over quite densely populated areas so it was seen and heard by tens of thousands of people, if not hundreds of thousands.
Most spectacularly, it was also captured by CCTV cameras which charted its journey across hundreds of miles of sky.
Heavens above ... 4.5 billion-year-old meteorite in the sky over North America
These images created a remarkable record of the meteorite as it streaked across the night sky at 12 miles per second, turning it blue.
The images helped a group of scientists to triangulate its impact site with far greater accuracy than is normally possible, allowing a team of meteorite hunters to search for the debris from the explosion in a precise location, a field near the Canadian city of Lloydminster.
Leading the team was University of Calgary professor Dr Alan Hildebrand, one of the world's leading meteorite experts and a member of the team behind the discovery of the ancient Chicxulub crater in the Yucatan peninsula of Mexico.
This vast crater, more than 112 miles in diameter, is thought to date back to the end of the Cretaceous period 65 million years ago and it remains the prime candidate for the catastrophic event that wiped out the dinosaurs.
Caught on camera ... a petrol station's CCTV camera shows the asteroid lighting up the scene as it passes overhead
Fortunately for the people of Canada, Dr Hildebrand's latest search is on a far smaller scale - however there is still a huge amount of information to be gleaned from this lightweight impact.
A ten-tonne rock travelling at 50 times the speed of sound has an extremely large amount of energy.
Dr Hildebrand says: "It would be like stocking up 400 tonnes of TNT to explode. It's really quite dramatic."
There is only one thing that can possibly protect the Earth's surface from a projectile with that amount of energy on a direct collision course with our planet - just one thing that can cause it to slow down and break up and so prevent all of the energy slamming into the Earth's surface in one place.
Night into day ... scene in Canadian town gets even brighter as the meteorite passes overhead
Night after night our atmosphere slows down and breaks up meteorites just like this one.
Entering the atmosphere at 12 miles a second and heading directly towards Buzzard Coulee from the depths of space, this lump of rock and iron that was originally about the size of a desk would have immediately begun to compress the thickening atmosphere gases in front of it.
When air is compressed it heats up and this in turn heats the meteorite until it is white-hot.
For a brief time, this billion-watt bulb shone high in the sky, then after just five seconds, its billion-year journey suddenly and dramatically came to an end as it disintegrated in a series of explosions, peppering the fields below with lumps of rock the size of golf balls.
In just a few seconds, this survivor from the distant past became just another part of planet Earth.
From the dawn of time ... fragment of the ancient meteroite
Canadian Press / Rex Features
It must have been quite incredible to be standing in Saskatchewan on that night as the sky turned blue, watching these heavy rocks raining down.
Hunting for meteorite fragments requires a certain kind of talent.
These rocks have streamed through the atmosphere with such intensity that their surface melts as it reaches temperatures of 6,000° Celsius - the surface temperature of the Sun.
This searing heat creates a telltale dark crust over the meteorite, so I was told we were looking for an oddly sculpted dark rock on the ground - a rock that Dr Hildebrand helpfully pointed out looks remarkably like the cow pats that litter this landscape.
However the mind-numbingly slow search felt well worth it when I did find one of the astonishing little rocks that were scattered across the frozen fields.
Each one of them had had an amazing history. They would have approached the Earth as part of a meteorite known as a chondrite.
Advertisement
Chondrites are very old, having formed at the very beginning of the Solar System more than 4.5billion years ago.
They have never been a part of a larger planet or moon - they are pure, wandering fossils of an earlier age.
If the meteorite had hit the ground intact, the explosion would have left a crater 65ft wide. Our planet was only spared this colossal impact because of the tenuous strip of gases that surrounds us, a strip of gas that we hardly notice.
But to experience the difference, mankind only needs to look to one of its near neighbours.
Nowhere is the crucial role of this protective blanket demonstrated more starkly than on the surface of Mercury - a battered, barren world that couldn't be more different from our own.
Extracted from Wonders Of The Solar System, out now, £20. Copyright © Brian Cox 2010. Adapted by Ben Jackson.
Read more:
http://www.thesun.co.uk/s(...)h.html#ixzz1352iGLiv