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Meteor Blast Over Bering Sea Was 10 Times Size of Hiroshima (theguardian.com)
A meteor explosion over the Bering Sea late last year unleashed 10 times as much energy as the atomic bomb that destroyed Hiroshima, scientists have revealed. From a report: The fireball tore across the sky off Russia's Kamchatka peninsula on 18 December and released energy equivalent to 173 kilotons of TNT. It was the largest air blast since another meteor hurtled into the atmosphere over Chelyabinsk, in Russia's south-west, six years ago, and the second largest in the past 30 years. Unlike the Chelyabinsk meteor, which was captured on CCTV, mobile phones and car dashboard cameras, the December arrival from outer space went largely unnoticed at the time because it exploded in such a remote location. Nasa received information about the blast from the US air force after military satellites detected visible and infrared light from the fireball in December.
Lindley Johnson, a planetary defense officer at Nasa, told BBC News that blasts of this size were expected only two or three times a century. The space agency's analysis shows that the meteor, probably a few metres wide, barrelled into Earth's atmosphere at 72,000mph and exploded at an altitude of 16 miles. The blast released about 40% of the energy of the meteor explosion over Chelyabinsk, according to Kelly Fast, Nasa's near-Earth objects observations programme manager, who spoke at the 50th Lunar and Planetary Science conference near Houston.
Lindley Johnson, a planetary defense officer at Nasa, told BBC News that blasts of this size were expected only two or three times a century. The space agency's analysis shows that the meteor, probably a few metres wide, barrelled into Earth's atmosphere at 72,000mph and exploded at an altitude of 16 miles. The blast released about 40% of the energy of the meteor explosion over Chelyabinsk, according to Kelly Fast, Nasa's near-Earth objects observations programme manager, who spoke at the 50th Lunar and Planetary Science conference near Houston.
Between Tunguska, Chelyabinsk, and now this, it's obvious to me that space hates Russia.
Planetary Defense Officer. That'd be sweet on a business card.
Where's all the click-bait on what would it be like if this happened over a major population center?
Learning HOW to think is more important than learning WHAT to think.
They're actually fairly common, with about 20-40 air bursts occurring each year. They're pretty evenly distributed. Russia just seems to get a disproportionate number because it has the most land area of any country by almost a factor of 2. It's also got a large population spread throughout that very large land area. The country covers pretty much the same latitude as Canada (second-largest country), but Canada is mostly deserted at higher latitutdes. So that increases the chances of a meteor being seen/recorded over Russia.
It's also worth noting that the ancient Egyptians also witnessed large meteor events and used the material to create jewelry for royalty and ceremonial weapons.
Lindley Johnson, a planetary defense officer at Nasa, told BBC News that blasts of this size were expected only two or three times a century.
Yet the last one was only six months ago!
What say you meteor-change deniers now??
But with climate change we can expect these much more often.
True. We can even calculate the expected increase.
The average temp of the earth's atmosphere is 14C or 287 K. So a 2 degree increase will expand the atmosphere by a factor of 2/287 or 0.7%. Since the atmosphere is roughy 100km deep, this is an extra 700 meters.
The mean radius of the earth is 6371 km, or 6471 including the atm, for a cross sectional area of 1.315e8 square km. With the extra 700 m, this will increase by 9060 sq km.
So with global warming we should expect a 0.02% increase in meteor impacts.
I don't remember any big explosions over Canada, the United States, China, Braille.
If it happened in Braille, we wouldn't see it.
If it happened in Braille, we wouldn't see it.
But we could feel the bump.
Planetary Defense Officer! Tell me this isn't the coolest job title in all of human history! Imagine chatting at a bar. "What do you do for a living? Neurosurgeon? Rocket Scientist?" and you reply "No baby...Planetary Defense Officer. Y'know this Earth thing? Yeah, I defend that."
In the end they will lay their freedom at our feet and say to us, Make us your slaves, but feed us. - Fyodor Dostoyevsky
Dead Hand wouldn't automatically launch a nuclear attack - it's more sophisticated and complex than that. It had a number of sensors for radiation, communication link availability, and other things in multiple places. If enough sensors triggered (e.g. high radiation in Moscow, loss of communication with fleet command in Vladivostok, etc.) it would allow two operators in a bunker to launch a nuclear strike on pre-programmed targets. It isn't a doomsday device in the sense of automatically launching a retaliatory attack. It's a system for ensuring that in the event of an attempted first strike that takes out the chain of command, someone will be able to launch a nuclear strike. The system wasn't designed to scare the USSR's enemies, it designed to make Soviet generals less trigger-happy, because they'd have the peace of mind that even in the event of a devastating attack, the USSR would have its revenge.
In any case, a meteorite wouldn't meet the requirements for activating the system. It wouldn't have the signature of a nuclear weapon (radiation and fission products), and it likely wouldn't take out communication with multiple command centres. Even if it did meet the requirements to activate the system, the result would be that some operators would be permitted to launch a nuclear strike, so there would still be two humans in the loop to realise what was going on.