Watching the skies for asteroids that could threaten Earth
20 August 2014 Last updated at 00:01 BST
When Jay Tate saw the comet Shoemaker Levy 9 plunge into Jupiter in 1994 - his first thought was "could it happen here?"
Attempts to warn the UK authorities about the potential danger of a meteorite strike got nowhere so he took action himself.
Setting up the Spaceguard Centre at an observatory in mid Wales, Jay began helping with global efforts to track and monitor the orbits of asteroids that could potentially be heading for Earth.
Now the operation is designated as the National Near Earth Observation Centre, but it still receives no official funding and is kept afloat by donations from visitors.
Video Journalist: John Galliver
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