A huge asteroid impact site recently discovered in Scotland highlights the clear and present danger of astral bodies like the one which closely passed Earth earlier this week ...

IN the somewhat fanciful plot of Hollywood blockbuster Armageddon, the ‘world’s greatest deep sea driller’ Harry Stiller – played by a stoic, steely-jawed Bruce Willis – has his unique skillset procured by NASA and finds himself blasted off to the surface of an incoming asteroid ... to blow it out of the sky with a nuclear bomb.

Highly dubious science aside, the Box Office success of Armageddon did serve to highlight a very real threat to the human race’s survival that is perhaps even more sobering than pandemics such as coronavirus – huge asteroids on a trajectory to Earth with the potential to wipe out much of the planet’s biological life.

Certainly, the astral body that flew past this Wednesday – Asteroid (52768) 1998 OR2, to give the two mile-long rock its Sunday name - would have wiped out much of the planet’s organic matter, if it hadn’t soared past at a relatively near-miss of 16 times the Earth-Moon distance. 

The Herald:

Asteroid (52768) was the biggest fly-by expected this year, with professional and amateur observers watching it pass as a slow-moving ‘star’. More visible to the naked eye, however - if life hadn’t been confined to the oceans at the time – would have been the huge object that smashed off the north west coast of Scotland 1.5 billion years ago, an event recently discovered by geologists.

A team of UK researchers have uncovered signs of a huge asteroid collision in the Stac Fada deposit in the Northwest Highlands, with rocks there containing high levels of chemicals found in asteroids. 

They also detected quartz crystals which have been subjected to intense pressures and heat - leading researchers to believe they have pinpointed the exact spot where the asteroid hit.

Academics from the University of Oxford and the University of Exeter claim the impact crater lies between nine and 12 miles off the coast in the Minch, which separates the mainland from the Outer Hebrides. 

Today, the spot is buried beneath water and rocks, rendering it inaccessible - so they pinpointed the possible site by studying the alignment of magnetic particles and  distribution of debris thrown outwards at the time of the collision.

“If you imagine debris flowing out in a big cloud across the landscape, hugging the ground, eventually that material slows down and comes to rest,” said study author Kenneth Amor. “But it’s the stuff out in front that stops first while the stuff behind is still pushing forward and it overlaps what’s in front.

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“That’s what we see and it gives us a strong directional indicator that we can trace backwards.”

The huge asteroid, estimated to have been between 0.6 and 1.2 miles wide, is believed to have struck when Scotland was a still a semi-arid environment located near the equator. Amor estimates the crater resulting from the impact spans almost nine miles in length, with a depth of around 1.9 miles – making it the biggest ever astral collision ever discovered in the UK.

Experts believe meteorite strikes were relatively common billions of years ago, as Earth and other planets were pelted with debris left over from the formation of the solar system. 

Amor says the new research marks such an exciting discovery because impact craters typically erode over time.“It was purely by chance that this one landed in an ancient rift valley where fresh sediment quickly covered the debris to preserve it,” he states.

Now that the crater’s possible location has been discovered, scientists aim to conduct targeted, 3D geophysical surveys of the Minch Basin.

High-resolution surveys could help the research team get a better sense of the dimensions of the crater - and might even have important implications for other celestial bodies if we learn more about their composition and trajectory.

“Impact craters on Earth are exceedingly rare,” Amor said. “The better we can understand how they formed the better we can understand observations on the rocky planets and moons of the solar system.”

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Space enthusiasts get ready to rock

Glasgow academics call for volunteers to help collect meteorites as part of UK Fireball Network

SCOTTISH scientists are turning their eyes to the skies to track meteorites – smaller, less threatening variations of their asteroid cousins - before they land on UK soil and want volunteers to help recover the space rocks wherever they fall.

The UK Fireball Network, led by researchers from the University of Glasgow and Imperial College London is setting out to place 10 cameras across the country to catch glimpses of the spectacular natural firework displays caused when meteoroids enter the Earth’s atmosphere.

It is part of a wider network called the Global Fireball Observatory operated by researchers in Australia at Curtin University.

Earlier this year in February, the network’s cameras filmed their first fireball, which dropped meteorites into the North Sea. 

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SKYFALL: Volunteers will help scientists search for traces of meteorites which have been tracked on camera.

While those are impossible to recover, the network team expect that future sightings that fall on the UK landmass can be properly triangulated to determine a landing area and send out a search party to find future meteorites.

Dr Luke Daly, of the University of Glasgow’s School of Geographical and Earth Sciences, is one of the leaders of the UK Fireball Network. He said: “Meteorites provide scientists with invaluable insights into other planets and our solar system. A good deal of what we know about the surface of Mars, for example, comes from analysis of chunks of the planet which were blasted off its surface by asteroid impacts millions of years ago and drifted in space before falling to Earth.

“Meteorites enter our atmosphere all the time, but the UK hasn’t had a great track record of finding them – in fact, it’s been nearly 30 years since one was last seen dropping into a back garden in Glatton in Cambridgeshire, and more than 100 since one was observed in Scotland.

“Camera networks like ours, and those of partner organisations like UKMON and SCAMP, give us a great chance to capture fireballs on multiple cameras. 

“Together we are building an integrated pipeline to use all the data from all the networks to track fireballs called the UK Fireball Alliance. 

“It was very exciting to capture our first images of a fireball caught by two of our observatories, although it was obviously disappointing that the material it dropped fell into the sea. 

“When we do catch sight of a fireball dropping meteorites on land, we’ll need the help of volunteers to help comb the countryside to find them, so anyone interested in making a little bit of history by getting involved can follow us on Twitter at @FireballsUK.”