Apophis 99942 is a 370-metre-wide near-Earth orbit space rock that continues to pose a destructive threat. Initial observations from NASA in 2004 revealed a probability of 2.7% that it could strike Earth in 2029. Further developments later ruled that date out, claiming it would pass through a gravitational keyhole setting up a future impact in 2036.
By late 2008, the probability that Apophis would pass through the gravitational keyhole was determined to be very small, ruling out an impact in 2036.
However, the threat is not completely eliminated.
NASA later admitted on February 21, 2013, there is a 150,000/1 chance of a direct impact with Earth in 2068.
Jay Melosh, an American geophysicist specialising in impact cratering, played out the shocking scenario on Amazon Prime’s “Asteroid Trackers”.
He said in 2009: “With Apophis, it is well enough identified that we would know pretty well where it will impact and when.
“If something like Apophis were to strike a city – let’s say it fell on Boston – it could create a ten-kilometre-wide crater.
“Almost all of metropolitan Boston would be destroyed.
“The sky would turn bright red and you would feel heat like there were six suns in the sky.
“Clothing would ignite, you would suffer third-degree burns, it would be devastating.”
However, Dr Melosh, who earned physics and geology degrees from Princeton University, revealed that mankind could be saved.
He added: “In space, we would use a mirror like a magnifying glass.
“As we hit the asteroid, we begin to vaporise material, and as it vaporises, the asteroid gets pushed the other way.
“What we would do with a real asteroid is focus some light on it until the rock vaporises.
“All we need to do is change the velocity of the asteroid by one centimetre a second.
“That tiny nudge over the year will push it off a collision course and save Earth.”