Call for asteroid defences

A major impact may have wiped out the dinosaurs

The UK should lead the way to creating an early warning system to defend the planet against potentially dangerous asteroids and comets, experts have told the UK Government.

A task force established to assess the threat of so-called Near Earth Objects (Neo's) has concluded that the risk is not science fiction but something that should be taken seriously.

The three-member team called on ministers to seek international partners to build a new £15m telescope dedicated to sweeping the skies for threatening objects.

The three-metre (9.8 feet) survey telescope, based in the Southern Hemisphere, would be designed to detect objects down to a few hundred metres across.

At present, objects of this size are only spotted accidentally in the course of other observations, mainly in the Northern Hemisphere, which is better served by telescopes.

Other recommendations of the official report included the setting up of an asteroid defence centre in Britain and working with the international community on ways to mitigate any future impacts.

International effort

The report made 14 recommendations. These included a plea that Britain should:

• take a leading role in a greater international effort;
• improve its ability to detect any incoming objects;
• assess the risks and consequences of an impact;
• implement measures to mitigate any future impacts and new national and international arrangements to cope with the many issues raised.

The government's science minister Lord Sainsbury set up the task force in January.

Speaking on Monday, Lord Sainsbury said the risk of a substantial object striking the Earth and causing major damage, though small, had to be taken seriously.

"The risk is extremely remote, we are talking about once every 100,000 years for a very serious incident," he told the BBC. "On the other hand, if it occurred, it would be very serious indeed.

"We put a lot of money into astronomy," Lord Sainsbury added. "I think it's sensible to put just a little bit into making certain that we know if there is any danger of an object hitting our very fragile planet."

'Global catastrophe'

The report listed nine objects that came within two lunar distances of the Earth - about 800,000 km (497,120 miles) - since 1991.

In May 1996, an object 300 metres (984 feet) wide, called JA1, came as close as 1.20 lunar distances from the planet.

Astronomers calculated recently that there are nearly 1,000 asteroids at least a kilometre (0.6 miles) wide which cross the Earth's path.

Professor Mark Bailey of Armagh Observatory in Northern Ireland said an asteroid of that size could have devastating effects on the Earth.

"This would cause a global catastrophe wherever it hit the Earth, via a climate change, and this would lead to a rapid cut-off of the food supply and ultimately within a few months to a loss of probably a quarter of the world's population," he told BBC radio.

The three-member taskforce comprised Dr Harry Atkinson, formerly of the Science and Engineering Research Council and past chairman of the European Space Agency's Council, with Sir Crispin Tickell, Britain's former ambassador to the UN and Professor David Williams, from University College, London.

The task-force, from left to right: Professor David Willams, Dr Harry Atkinson (Chairman) and Sir Crispin Tickell.

Lord Sainsbury said he welcomed the task force's approach and would be considering the government's response to the recommendations over the next couple of months.

The Liberal Democrat MP Lembit Opik, who campaigned for the task force to be set up, called for £70m ($98m) to be spent globally over 10 years on technology to track approaching asteroids.