near-Earth object (NEO), a scientific designation for a space objectthat’s a whole lot easier to pronounce if you just say “comet” or “asteroid,” is hurtling toward Earth’s general neighborhood at Bifrost-like speed, passing close enough for NASA scientists to place it on their “potentially hazardous asteroid” — or PHA — watch list.
The asteroid, which deserves a better name than the 2016 NF23 designation it’s been handed, is motoring toward our corner of the solar system at a speed of roughly 20,000 miles per hour, putting it on schedule to be nearest us humans by Aug. 29.
NASA estimates the asteroid to be between 70 and 160 meters (230 to 525 feet) across, and expects it — with a “reasonably low uncertainty” — to pass within 0.03377 astronomical units (about 3 million miles) from Earth. The object has an absolute magnitude (a measure of brightness when observed from a standard vantage) of 22.9, which is just dim enough to assuage scientists’ concerns that it’s on a trajectory to make a direct impact.
Three million’s a big-sounding number, sure, but for comparison, our sun is 93 million miles away. And in order to earn the distinction of being tagged as an NEO, an object can pass at a much, much greater distance from Earth — roughly 30 million miles — and still qualify.
2016 NF23 isn’t the only asteroid that’s grazing Earth’s environs this month. Another NEO, the scintillatingly named 1998 SD9, is expected to pass even closer (0.01083 astronomical units, or 1 million miles) around the same time as its bigger buddy. But fortunately, 1998 SD9 is a heck of a lot smaller at approximately 38 to 86 meters (125 to 280 feet), and, as its name suggests, it’s more of a known quantity: NASA’s been watching it since its discovery all the way back in 1998.
As for 2016 NF23, NASA isn’t sounding any alarms or marshaling Bruce Willis to mount an emergency asteroid landing. But since it’s only been on the agency’s radar since 2016, NASA’s still in the early stages of discerning its orbit. And since it falls right on the edge of NASA’s PHA sweet spot (a PHA object must pass closer than 0.05 astronomical units and have an absolute magnitude 22.0 or less), it’s at least making headlines — just not the kind you see in asteroid apocalypse movies like Armageddon.
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