When a six mile-wide (10km) asteroid struck just off the coast of modern-day Mexico 66 million years ago, the resulting fallout contributed to the extinction of the dinosaurs and approximately 75 percent of all life on Earth.
But even smaller impacts can sow chaos and confusion.
When a 65ft-wide (20m) exploded in the skies over Russia’s Chelyabinsk Oblast in 2013, the airblast blew out windows in a wide radius and injured more than 1,500 people with shards of glass.
Professor Womersley said: “NASA estimates that only a small fraction of the large objects that might one day strike the earth have yet been tracked, and more are being discovered all the time.
“We know impacts don’t happen very often, but we know that they do happen, and that they have the potential to do great damage.”