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The Sound So Loud That It Circled the Earth Four Times

nautil.us

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Re: The Sound So Loud That It Circled the Earth Four Times

#2
For anyone interested, I'd recommend Simon Winchester's book "Krakatoa": http://www.amazon.com/Krakatoa-World-Exploded-August-1883/dp...

Also interesting are how quickly the volcano has risen out of the sea again after being totally obliterated, and how much life now thrives on it.

Re: The Sound So Loud That It Circled the Earth Four Times

#3
Hey, I'm the author of the post (on twitter @aatishb). Thanks for voting it up. Would love to hear your thoughts and constructive feedback. Cheers. (PS the references linked to at the bottom of the post are packed with fascinating information about Krakatoa, for anyone who wants to dig deeper.)

Re: The Sound So Loud That It Circled the Earth Four Times

#4
post #3

Hey, I'm the author of the post (on twitter @aatishb). Thanks for voting it up. Would love to hear your thoughts and constructive feedback. Cheers. (PS the references linked to at the bottom of the post are packed with fascinating information about Krakatoa, for anyone who wants to dig deeper.)

I was also captivated by this vivid first person account of a Dutch pilot in the coastal town of Anjer who survived the ensuing Tsunami http://www.vansandick.com/familie/links/vulcaan2.php#h1

Re: The Sound So Loud That It Circled the Earth Four Times

#5
Nice. I hadn't thought of there being a limit (due to vacuum) to sound intensity.

Reminds me of this recent comment on reddit: http://np.reddit.com/r/space/comments/2h9y9g/the_first_launc...

"the Saturn V rocket produced a SWL (Sound Power Level) of about 220 decibels, which is sufficient to melt concrete nearby and set grass aflame a mile away,"

Re: The Sound So Loud That It Circled the Earth Four Times

#6
post #3

Hey, I'm the author of the post (on twitter @aatishb). Thanks for voting it up. Would love to hear your thoughts and constructive feedback. Cheers. (PS the references linked to at the bottom of the post are packed with fascinating information about Krakatoa, for anyone who wants to dig deeper.)

How does something like the Tzar bomb compare in terms of sound pressure? Would the immense volume of ejected material from the volcanic explosion move more air than a nuclear explosion? I'd guess lots of mass (air molecules) is just vaporized in a nuclear explosion, leaving much less mass to create pressure deltas.

Re: The Sound So Loud That It Circled the Earth Four Times

#8
post #3

Hey, I'm the author of the post (on twitter @aatishb). Thanks for voting it up. Would love to hear your thoughts and constructive feedback. Cheers. (PS the references linked to at the bottom of the post are packed with fascinating information about Krakatoa, for anyone who wants to dig deeper.)

How does something like the Tzar bomb compare in terms of sound pressure? Would the immense volume of ejected material from the volcanic explosion move more air than a nuclear explosion? I'd guess lots of mass (air molecules) is just vaporized in a nuclear explosion, leaving much less mass to create pressure deltas.

That was my first thought, too. Fun facts [1]:

- its ignition was the most powerful artificial explosion in human history

- The seismic shock created by the detonation was measurable even on its third passage around the Earth

[1] http://en.wikipedia.org/wiki/Tsar_Bomba

Re: The Sound So Loud That It Circled the Earth Four Times

#9
post #3

Hey, I'm the author of the post (on twitter @aatishb). Thanks for voting it up. Would love to hear your thoughts and constructive feedback. Cheers. (PS the references linked to at the bottom of the post are packed with fascinating information about Krakatoa, for anyone who wants to dig deeper.)

How does something like the Tzar bomb compare in terms of sound pressure? Would the immense volume of ejected material from the volcanic explosion move more air than a nuclear explosion? I'd guess lots of mass (air molecules) is just vaporized in a nuclear explosion, leaving much less mass to create pressure deltas.

Wikipedia says it was four times as powerful as Tzar Bomba, which would put it in the neighborhood of 200Mt. Technically Tzar Bomba was suppose to yield about 100Mt, but the scientists dialed it down a bit because they were worried about it.

Re: The Sound So Loud That It Circled the Earth Four Times

#10
post #3

Hey, I'm the author of the post (on twitter @aatishb). Thanks for voting it up. Would love to hear your thoughts and constructive feedback. Cheers. (PS the references linked to at the bottom of the post are packed with fascinating information about Krakatoa, for anyone who wants to dig deeper.)

How does something like the Tzar bomb compare in terms of sound pressure? Would the immense volume of ejected material from the volcanic explosion move more air than a nuclear explosion? I'd guess lots of mass (air molecules) is just vaporized in a nuclear explosion, leaving much less mass to create pressure deltas.

The Tsar bomb was in the ballpark of a 50 megaton explosion, whereas estimates that I've seen for Krakatoa put it at up to 200 megatons. That said, there would be differences due to the fact that h-bombs are exploded at a height to maximize the damage from the blast wave, and that a significant fraction of Krakatoa's energy would have been spent on throwing earth around. It's always hard to compare different explosions because it's difficult to know what fraction of the energy output goes into acoustic energy, but I think it's reasonable to assume that Krakatoa was louder (at least in that the sound was heard further).
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