A “city killer” asteroid whizzed past earth Thursday that “would have hit with over 30 times the energy of the atomic blast at Hiroshima,” according to one astronomer professor.

Long-time Slashdot reader SonicSpike shared a Washington Post story that begins with a reaction from Alan Duffy, lead scientist at the Royal Institution of Australia:
“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 metres wide (187 to 427 feet), and moving fast along a path that brought it within about 73,000 kilometres (45,000 miles) of Earth. That’s less than one-fifth of the distance to the moon and what Duffy considers “uncomfortably close….”

The asteroid’s presence was discovered only earlier this week by separate astronomy teams in Brazil and the United States. Information about its size and path was announced just hours before it shot past Earth, Brown said. “It shook me out my morning complacency,” he said. “It’s probably the largest asteroid to pass this close to Earth in quite a number of years.”

So how did the event almost go unnoticed?

Scientists have spotted 90% of asteroids that more than half a mile wide — but this asteroid was smaller, faster, and had an unusual orbit.

“It should worry us all, quite frankly,” one scientist told the Post. “It’s not a Hollywood movie. It is a clear and present danger.”

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Source:: Slashdot