You may not have noticed it as you slept comfortably in your bed this morning, but Planet Earth narrowly escaped a catastrophic collision with a 1.6-mile wide asteroid, The Telegraph is reporting.
“Narrowly escaped” may be overstating things a bit, as the asteroid came within 15 million miles of the Earth (by comparison, the distance from the Earth to the Moon is about a quarter of a million miles). As far as NASA is concerned, 15 million miles is a near miss, when it comes to asteroids.
NASA’s sky watchers have had their eyes (well, their telescopes and their computer simulations) on the asteroid, named Asteroid 86666 (2000 FL10), which is believed to be as much as 1.6 miles wide and hurtling through space at 40,000 miles per hour. As recently as Thursday, computer simulations had the asteroid on track to come within the Moon’s orbit of the Earth, according to The Mirror. In astronomical terms, that’s basically point-blank range.
Giant Asteroid 86666 is heading for Earth this weekend http://t.co/iRINzIttYr
— Andy-0163631063 (@arenajualan) October 10, 2015
NASA considers an asteroid “potentially hazardous” if it comes within 4,600,000 miles of the Earth, which is about 18 times the distance between the Earth and the Moon. Had the asteroid actually hit the Earth, the effects would have been devastating. Bill Napier, professor of astronomy at the University of Buckinghamshire, in remarks via The Express, compared the damage potential of this asteroid to that of the 1908 Tunkguska event. On June 30, 1908, an asteroid — or perhaps a comet — exploded in the atmosphere about three to six miles above the surface of the Earth in the remote, northern Russian region of Siberia. The shock wave from the blast flattened nearly a thousand square feet of forest, and registered 5.0 on the Richter Scale. Fortunately, the event took place in a remote, sparsely-populated area, and there were no known human casualties.
An impact from Asteroid 86666 would have made Tunguska look like child’s play. Professor Napier says that, had it hit the Earth and struck in a populated area, it could “take out a small country.”
“If the Tunguska event had hit London it would have destroyed the region out to the M25.”
Asteroid 86666 did not hit the Earth, but today’s near miss doesn’t necessarily mean that we are out of the woods. NASA has a program to watch the skies for potentially dangerous asteroids, called Near Earth Objects (NEOs) in scientific parlance, and they’ve got their eyes on several. None are expected to come anywhere near the Earth within the next couple of decades.
It’s the asteroids that NASA doesn’t know about that are the problem, however. By the best estimates, NASA has identified and tracked about one percent of all possible deadly asteroids. Many of the asteroids that have been identified are in chaotic orbits that can change at a moment’s notice, says Professor Napier.
“The danger is in the future if asteroids like this are nudged off their orbit they can effectively become missiles. There are a lot of asteroids out there with the potential to be hazardous which have not been discovered.”
One such asteroid, which no one saw coming, exploded over the skies of Chelyabinsk, Russia on February 15, 2013 (objects like asteroids are termed a “meteor” once they enter the Earth’s atmosphere).
The shock wave from that particular explosion shattered windows, set off car alarms, and sent at least 1,500 people to area hospitals; those injuries were largely due to damage from the blast — such as shattered glass — and not due to the blast itself).
Of the currently known NEO asteroids, the next one that will likely come close to the Earth is expected to pass by in 23 years.
[Photo by Vadim Sadovski/Shutterstock]