Asteroid impacts on Earth are infrequent, particularly large ones that cause great damage. Yet near misses are a dime a dozen. According to NASA, about 20 known asteroids approach each year within 239,000 miles of Earth—or closer than the average distance from us to the moon. Two such flybys occurred yesterday and one will occur today, passing roughly 217,000 miles, 105,000 miles and 38,500 miles away, respectively.
The earliest known hit from a space rock occurred around 3 billion years ago in Greenland, where scientists recently discovered a 62-mile-wide impact zone. Other large collisions are believed to have taken place 2 billion years ago in South Africa, 1.8 billion years ago in Canada, 580 million years ago in Australia, 364 million years ago in Australia and 215 million years ago in Canada, an impact that created the ring-shaped Lake Manicouagan. Even more famously, an asteroid or comet smashed into Mexico’s Yucatán Peninsula 65 million years ago, purportedly helping to wipe out the dinosaurs.
The 20th and 21st centuries have also seen their share of objects raining down from space. In 1908 a celestial body exploded in the air over a remote part of Siberia, felling some 80 million trees and releasing the energy equivalent of about 1,000 Hiroshima atomic bombs. Three years later, a meteorite apparently killed a dog in Egypt. In 1954 a meteorite crashed through the roof of a house in Alabama and struck a sleeping woman on the hip, bruising her but doing no lasting damage. And in 2007 a meteorite left a toxin-filled crater near Peru’s Lake Titicaca. Another incident occurred on February 15, 2013, when a small asteroid violently exploded over Chelyabinsk, Russia. Over 1,000 people were injured that day, mainly from shattered glass. NASA moreover reported that an asteroid the size of a car had entered our atmosphere this January 1 over the mid-Atlantic Ocean.
Additional activity took place yesterday, though nothing as dramatic as a collision. At 4 p.m. EST, asteroid 2014 DX110, approximately 100 feet wide and moving over 33,000 miles per hour, passed about 217,000 miles from Earth. Then, a few hours later, asteroid 2014 EF, approximately 16 feet wide and moving nearly 34,000 miles per hour, passed about 105,000 miles from Earth. Finally, today at about 4:20 p.m. EST, asteroid 2014 EC, approximately 26 feet wide and moving over 35,000 miles per hour, passed about 38,500 miles from Earth. “You could say it’s a little unusual that we have three in a row,” said Paul Chodas, a NASA research scientist who computes the orbits of asteroids and comets. “But they’re not related. It’s simply random.”
NASA is unaware of any other relatively close buzzes coming up over the next two months. Nonetheless, more discoveries could be made. For example, asteroids 2014 DX110, 2014 EF and 2014 EC, invisible to the naked eye, were all first spotted this past week. “The observatories doing asteroid searches are getting better and better,” Chodas explained. “In the past, we’d have events like this and we wouldn’t have known about them.” In order to get more information on the potentially dangerous bodies out there, NASA conducts periodic meetings and workshops with the public. With enough time, Chodas said, an asteroid could be deflected, or an area of Earth could be evacuated. Perhaps that will be necessary with 2014 EC, which NASA estimates has a miniscule chance of striking the planet between 2056 and 2079.