Meteor Fragments Hit the Southeast U.S. Here's What to Know

Time​ Magazine

2 days ago

The inner solar system is a lot calmer than it was 4 billion years ago, during what's known as the heavy bombardment period. Over the course of that violent stretch, which lasted about 500 million years, Mercury, Venus, Earth, Mars, and the moon were regularly pounded by asteroids, meteors, and other cosmic ordnance, many of the objects as big as the six-mile-wide rock that wiped out the dinosaurs. Things have gotten a lot quieter since then, but that's not to say everything has gone entirely still. Earth still lives inside a shooting gallery, with thousands of objects—totaling about 48.5 tons per year, according to NASA—entering the atmosphere.
Yesterday, one of those space boulders exploded in the skies over Alabama, Tennessee, Georgia, North Carolina, and South Carolina at 11:51 a.m EDT, according to the National Weather Service (NWS). The brilliant flash, which was accompanied by a sonic boom that many mistook for an earthquake, resulted in hundreds of calls and posts to the American Meteor Society (AMS), NASA's recommended organization for reporting meteoric fireballs. In Henry County, Ga., one house was struck by debris that broke through the roof and landed inside the residence. There were no reported injuries.
'The Henry County Emergency Management Agency [EMA] passed along to us that a citizen reported that a 'rock' fell through their ceiling around the time of the reports of the 'earthquake,'' the NWS said in a Facebook post. 'Henry County EMA also reported that the object broke through the roof, then the ceiling, before cracking the laminate on the floor and stopping.'
The possibility of something tumbling from the skies this week was not entirely unexpected. Yesterday's event occurred during the ongoing Bootid meteor shower, which happens once every 6.37 years, when Earth passes through the remnants of the tail of Comet 7P/Pons-Winnecke. The Bootid is just one of dozens of known showers the AMS lists on its website. Many of those events produce only a fine mist of meteor fragments, visible only at night in dark conditions away from city lights, and commonly called shooting stars.
Yesterday's rock was of a decidedly greater caliber, one big enough to be classified as a bolide, a meteor with enough mass to cause a bright flash and a sonic boom as it slams into the atmosphere, but too small for most of it to reach the ground without being incinerated first. To qualify as a bolide, an incoming meteor must reach the brightness of Venus, which, like the moon, is often visible in the daytime sky. A few dozen bolides occur each year, according to NASA.
The most explosive recent bolide event occurred over Chelyabinsk, Russia, on Feb. 15, 2013, when an object estimated to have measured about 65 ft., detonated in the atmosphere, injuring nearly 1,500 people and damaging 7,200 buildings. Modern history's biggest bolide also struck Russia, in the celebrated Tunguska event of 1908, when a 350-ft. meteor flattened 830 sq. mi. of forest land.
Lesser meteoric fireworks are much, much more common than bolides. According to the AMS, several thousand small fireballs erupt in the atmosphere every day, but 'the vast majority of these,' the organization says, 'occur over the oceans and uninhabited regions, and a good many are masked by daylight.'
Notwithstanding the Henry County house that got hit by the recent bolide, the odds of any one spot—or any one person—being struck by space debris are vanishingly small. Barely 5% of objects that enter the atmosphere survive the fires of entry and reach the surface. Roughly 70% of that surface is ocean and much of the rest is desert or other sparsely inhabited terrain. Finally, most of the meteorites that do strike the planet are, by the time of impact, micrometeorites—too small to do any damage at all. In all of known human history, in fact, there is only one person who is believed to have been killed by a meteorite—an Indian bus driver who was struck while walking on the campus of an engineering college in the state of Tamil Nadu on Feb. 6, 2016. That effectively puts your odds of meeting the same fate as one in the total number of human beings who have walked the Earth since the dawn of homo sapiens roughly 300,000 years ago.
That's not to say there haven't been close calls. On May 1, 1860, a horse was killed by a meteorite strike in Concord, Ohio. In 1954, an Alabama woman—whose picture was published and story was told in the Dec. 13, 1954 issue of LIFE magazine—sustained severe bruising to her hand and side when a 10 lb. meteorite crashed through her roof while she lay napping on her sofa. Put yesterday's event in the category of lightning strikes or shark bites—theoretically possible, highly improbable, one more thing you can take off your worry list.