An asteroid that is approximately one-mile wide will come very close to the Earth on May 14, according to NASA's Near Earth Object watch. While an asteroid of this size would be cataclysmic if it hit the Earth, this one will pass safely by.

The asteroid, designated 1999 FN53, is the largest object currently being tracked on NASA's near Earth radar. It was first discovered in March 1999 as is on course to fly past Earth at a speed of almost 14 kilometers per second or about twice the speed of a rocket at liftoff at a distance of 26.4 lunar distances, or about 10 million kilometers.

While there are other objects that come even closer to the Earth than 1999 FN53, none are as large. This has prompted speculation as to what would happen if an asteroid did, in fact, hit our planet.

It would undoubtedly lead to the deaths of around 1.5 billion people, we are looking at a mass extinction of humanity," says Bill Napier, professor of astronomy at the University of Buckinghamshire.

He also said that these immediate deaths wouldn't be the end of it. "If it were to strike the sea it would send a plume of halogen gasses into the stratosphere destroying the ozone layer. This would allow unrestricted sunlight to hit the Earth, the sky would heat up becoming strong enough to burn vegetation."

However, despite these predictions, currently there is no need to panic. There is no indication that 1999 FN53 will hit Earth or even come close enough to affect it in any way. It is also not even on NASA's Near Earth Objects risk table, which lists objects with impact probably as low as one in 9 million.

This asteroid isn't the only one to come close to the Earth this year. Next month, an asteroid codenamed Icarus, which is one-kilometer wide and flies almost three times faster than FN53, will pass even closer to the Earth at only 21 lunar distances.

Then an even larger asteroid, whose diameter measures between 1 and 2.3 kilometers is expected to pass by the Earth at only 18.8 lunar distances from us at a speed of 20 kilometers a second. None of these bodies are expected to affect the Earth in any way.

If you are wondering what would happen, an indication of what would happen occurred in February 2015, when a bolide just 20 meters across exploded in the atmosphere above a Russian city. The blast was 500 kilotons strong, which is 20 to 30 times more powerful than the bomb dropped on Hiroshima. While no one was killed, the shockwave shattered windows and damaged buildings causing injuries to 1,500 people.