An asteroid deflection.

For those who cannot visualize how big their asteroid should be, there is even a helpful drop-down menu of pre-set sizes which include ‘school bus’, ‘humpback whale’, ‘Empire State Building’ all the way up to the ominous-sounding ‘small planet’. The website’s algorithms then calculate what the effects of the asteroid’s impact would be on the Earth’s axis, whether there would be a fireball– and what chance of surviving any bystanders would have. It even tells you how far you should be from the impact to avoid being buried in the material thrown up from any crater that is left behind. The website, called Impact Earth! is the brainchild of scientists from Purdue University in the U.S and Imperial College London.

It is an update of a calculator which was originally devised in 2004 and which is based on scientifically sound calculations. The new version includes extra elements such as the height of resulting tsunami waves and it comes with an entertaining animation that shows the asteroid hurtling from space towards Earth. The asteroid is identical to the Hartley 2 comet that Nasa Deep Impact spacecraft flew by yesterday. An image of the comet Hartley 2 which was pictured yesterday, the image on the website bears a striking resemblance to the cometImperial's Dr Gareth Collins told the BBC: ‘One of the major new additions is the estimates for tsunami wave height at a given distance away from an ocean impact. ‘This had been a popular request, but we didn't put it in the original calculator because there simply wasn't consensus back then on what the hazard was. There's since been some good research and we now have a better understanding of the issue. On average, an object about the size of car will enter the Earth's atmosphere once a year, producing a spectacular fireball in the sky.

"The site is intended for a broad global audience because an impact is an inevitable aspect of life on this planet and literally everyone on Earth should be interested," said Dr Melosh. The team is also looking at using the Impact Earth data to map potential asteroid hits onto Google Earth. Artist's impression of the Chicxulub crater on the Yucatan peninsula in Mexico. The massive impact of the asteroid may have been responsible for the extinction of the dinosaurs. A survey of the stars known as Pan-STARRS has been set up by astronomers to monitor the skies for any incoming asteroids. Any sizable object that looks like it may come close to Earth within the next 50 years or so will be labeled 'potentially hazardous' and carefully monitored. NASA experts believe that, given several years warning, it should be possible to organize a space mission to deflect any asteroid that is discovered to be on a collision course with Earth. An asteroid collision with Earth is believed to have wiped out the dinosaurs. Wise labs have been pushing for 10 most risk to humanity say the impact sent a vast flume of dust into the atmosphere 65 million years ago, unleashed a torrent of powerful earthquakes and triggered forest fires across North America, blocking out the sun and wiping out half of all species. Finally visit the Impact Earth website at purdue.edu or impactearth.