A giant telescope lens made by a Denbighshire firm is helping US scientists monitor rogue asteroids on a collision course with Earth.
Thousands of potentially lethal space objects need to be identified
The 1.2m (47in) lens made at Technium OpTIC, based at St Asaph, is being installed at the University of Hawaii.
The Nasa-run Pan STARRS project (PANoramic Survey Telescope & Rapid Response System) aims to track objects as small as 300m (330 yards) across.
Images from the lens are recorded by a 1.4 billion-pixel digital camera.
A growing number of scientists are taking seriously the threat posed to the planet by an asteroid collision.
In 2005, NASA was given the task of detecting 90% of near-Earth objects with a size greater than 140m in diameter by the year 2020.
The agency estimates there are about 20,000 undiscovered potentially-threatening asteroids.
The Pan-STARRS project is capable of detecting objects 300m in diameter - large enough to have catastrophic consequences.
John Oliver, of Technium OpTIC, based on St Asaph Business Park, said the research programme in Hawaii contacted them because of a worldwide manufacturing shortfall in the type of lens used.
The lens is key to the telescope being assembled in Hawaii
He said: "All our tests on the lens showed that it should perform they way they are looking for.
"Millions of these near-Earth objects pass through our solar system every year. If only one hit us, we'd have a big problem."
He said the company had a new machine which enabled them to polish the lenses to the high standard and tolerance Nasa required.
Lembit Opik, MP for Montgomeryshire, has called on the UK government to devise a plan to combat the threat of asteroids.
He welcomed the firm's involvement with the project, adding: "I regard this initiative as part of our global insurance policy against cosmic catastrophe."