Syracuse, N.Y. – A million or more years ago, a 1-ton chunk of rock escaped the asteroid belt between Mars and Jupiter, bound for Syracuse.
The rock and Earth, both pulled in separate orbits by the sun, dodged each other for millennia.
Until just after noon Wednesday, when that meteor crashed into Earth’s atmosphere above Central New York, rattling windows, tripping earthquake detectors and scattering ancient debris as it burned at temperatures half as hot as the sun.
“It’s probably been crossing the Earth’s path countless times, until its time was up in 2020,” said Robert Lunsford, fireball report coordinator for the American Meteor Society. “The chance of a collision is infinitesimal, but if you do it several million times, it finally happens.”
Thousands of meteors hit Earth every year, but most go unnoticed because they’re too small to see and because most of the planet is ocean or uninhabited land. This week was the rarest of rare occurrences: A meteor big and brilliant enough to see during daylight, striking the sky above a densely populated region where millions of people could experience it.
“Anyone who got to see it should remember it forever, because it’s not something most people will ever get to witness,” said Zoe Learner Ponterio, manager of Cornell University’s Spacecraft Planetary Image Facility. “If you drew a 1-kilometer square in your yard, you’re only going to get a meteor to hit that space once every 50,000 years.”
Thanks to one of the cloudiest climates in the country, unfortunately, most Central New Yorkers didn’t get to witness the meteor. But it was captured on video in Western New York and Toronto, and people from Virginia to Ontario heard the deafening boom that sounded to some like gunshots or a falling tree. As one of the 181 observers who filed reports with the meteor society put it: “Scared the bejesus outta me.”
Based on those reports, the society calculated that the meteor hit the atmosphere above Lake Ontario and disintegrated just south of Rochester. NASA’s estimated trajectory shows a different path, with the meteor striking above Syracuse and diving southwest toward the Finger Lakes for 3 seconds before flaming out. It was only 22 miles high at that point, which is a long way for a meteor to penetrate the atmosphere.
NASA has three meteor-tracking cameras in Ohio and western Pennsylvania that would have given a precise path, but they were off at the time.
“Meteor cameras don’t turn on until night because they’re too sensitive to the sun,” explained Bill Cooke, who tracks meteors for NASA.
This meteor was so bright that it was captured by a NASA satellite that monitors lightning. The bits of debris scattered after the meteor exploded could likely be seen on National Weather Service radar. And the sonic boom was detected in Ontario by a seismograph, the instrument that records earthquakes.
When the meteor finally got hot enough to explode, Cooke said, it released as much energy as 66 tons of dynamite.
“When it broke apart it produced a shock wave that produced the sonic boom that people heard,” he said.
The meteor was just under 3 feet across and weighed about 1,800 pounds, NASA estimated. That’s hefty as meteors go: The shooting stars seen in annual meteor showers are not bigger than small pebbles or golf balls.
Wednesday’s meteor crashed into the atmosphere at 56,000 mph.
“That’s slow for a meteor, actually,” Cooke said. “Some, like the Leonids, move at 150,000 mph.”
The relatively sluggish speed indicates that the meteor probably broke loose from the asteroid belt that lies between Mars and Jupiter, about 92 million miles from Earth. That’s as far from Earth as the sun is.
As the meteor pushed through Earth’s increasingly thickening atmosphere, it reached an estimated temperature of 5,000 degrees Fahrenheit. For comparison, the surface of the sun is a little less than 10,000 degrees.
Cooke said the rock – technically called a meteoroid before it hits the Earth’s atmosphere and becomes a meteor — was the color of pencil lead. As it burst into a fireball, it emitted light 100 times brighter than a full moon.
The meteor was big enough that some pieces might have stayed intact and rained down on the earth, Lunsford said.
“It’s possible that some small fragments might have landed somewhere between Rochester and Syracuse,” he said.
The pieces that fall to Earth, probably no bigger than charcoal briquets, are called meteorites. They’re black and appear burnt, because that’s exactly what they are.
“They would look pitted, similar to lava,” Lunsford said. “That’s very alien to the normal rocks you would find.”
Those alien meteorites can be valuable, and a cottage industry of meteorite-seekers hunt for them. Lunsford said the pieces would likely be scattered in an area about 25 miles in diameter at the end of the meteor’s trajectory. NASA’s rough estimate shows the meteor’s path ending at the northern tip of Cayuga Lake, while the meteor society places the endpoint about 60 miles to the west.
That’s several thousand square miles of potential debris field. Learner Ponterio, whose museum at Cornell has a collection of meteorites, said meteorite hunters shouldn’t get their hopes up.
“Finding a piece on the ground is a pretty rare occurrence, and almost always when someone thinks they found one it turns out to be something else,” she said.
Meteors strike Earth every day, and big fireballs like Wednesday’s happen somewhere in the U.S. once a month, Cooke said. But this week, that somewhere was our somewhere.
“They’re not uncommon,” Cooke said. “But if you see it, that’s a rare event.”
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