Guest essay by Eric Worrall
This asteroid, estimated between 187 to 426ft wide and 55,000MPH, passing just 45,000 miles from Earth, wasn’t detected until a few days ago.
‘It snuck up on us’: Scientists stunned by ‘city-killer’ asteroid that just missed Earth
By Allyson Chiu
July 26Alan Duffy was confused. On Thursday, the astronomer’s phone was suddenly flooded with calls from reporters wanting to know about a large asteroid that had just whizzed past Earth, and he couldn’t figure out “why everyone was so alarmed.”
“I thought everyone was getting worried about something we knew was coming,” Duffy, who is lead scientist at the Royal Institution of Australia, told The Washington Post. Forecasts had already predicted that a couple of asteroids would be passing relatively close to Earth this week.
Then, he looked up the details of the hunk of space rock named Asteroid 2019 OK.
“I was stunned,” he said. “This was a true shock.”
This asteroid wasn’t one that scientists had been tracking, and it had seemingly appeared from “out of nowhere,” Michael Brown, a Melbourne-based observational astronomer, told The Washington Post. According to data from NASA, the craggy rock was large, an estimated 57 to 130 meters wide (187 to 427 feet), and moving fast along a path that brought it within about 73,000 kilometers (45,000 miles) of Earth. That’s less than one-fifth of the distance to the moon and what Duffy considers “uncomfortably close.”
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The odds of a city buster or larger hitting Earth might be low, but the consequences of a major impact in a populated area would be high.
The unexpected Chelyabinsk meteor in 2013 shows it is possible for cities to be affected by unexpected cosmic visitors.
Nobody really knows how many of these dangerous objects are on orbits which intersect the Earth.
If NASA left climate monitoring to NOAA, and spent more time and money monitoring space, the next near miss or worse might not be such a surprise.
via Watts Up With That?
July 29, 2019 at 08:58AM
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