typodupeerror

## Fifth Anniversary of a Cosmic Onslaught162

The Bad Astronomer writes "Five years ago today (December 27, 2004), a vast wave of high-energy gamma and X-rays washed over the Earth, blinding satellites and partially ionizing the Earth's atmosphere. The culprit was a superflare from the magnetar SGR 1806-20, located 50,000 light years away. The energy released was mind-numbing: in one-fifth of a second, this supercharged magnetic neutron star blasted out as much energy as the Sun does in 250,000 years!"
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## Fifth Anniversary of a Cosmic Onslaught

• #### Re:Frist Post! (Score:5, Informative)

on Sunday December 27, 2009 @02:04PM (#30564610) Journal

Assuming that we are working with the standard burning library of congress as the measuring unit, we can define the energy release in those terms:
1 Burning Library of Conress (BLOC)
4kcal/g
20TB data
1MB/novel
1 novel = 200g
4,000 metric tons
16 billion kcal

Solar output ~~ 10^22 kcal/second
250,000 years = 8*10^12 seconds

energy of event: 8*10^35 kcal
energy of event/BLOC ~~ 5*10^25 burning libraries of congress
1 billion BLOC/second for 1.7 billion years

• #### Re:Frist Post! (Score:1, Informative)

by Anonymous Coward on Sunday December 27, 2009 @02:10PM (#30564634)

8*10^34 not 8*10^35 however, the calculation is still largely correct as 10^35 was a typing error.

• #### Re:50005 years ago? (Score:2, Informative)

by Anonymous Coward on Sunday December 27, 2009 @03:10PM (#30565034)

5 years ago is "Earth receive time".
50005 years ago is when it happened in Earth's frame of reference.

There is no objective time, but that's not a reason to go on a crusade and burn every calendar and clock we have. We're on Earth, so we use Earth's frame of reference.

• #### Re:Frist Post! (Score:3, Informative)

on Sunday December 27, 2009 @04:24PM (#30565674) Journal

Technically the error occured at the step that calculates the solar output. The Sun puts out 1400W/m^2 electromagnetic radiation at Earth's orbital distance of ~150 million km. The total output is equal to the surface area of the orbit (4*pi*r^2) which is 4*(3.14)*(1.5*10^11)^2 = 4*10^26 W for which 1 kcal/sec = 4180 W which means ~10^23 kcal/sec energy is released. Doin the math leads to 10^35 being the correct answer leaving the remainder of the math quite correct.

• #### Re:Zero warning (Score:5, Informative)

on Sunday December 27, 2009 @04:52PM (#30565856) Journal

You're misunderstanding what a negative argument is.

Go try to test this hypothesis: "No rat can survive 2+ hours in 0degree salt water, ever."

You can test it all you like, with a million rats if you so desire. But you can never confirm it, even if you test a million of them. There might be some rat genotype out there capable of surviving, and you can't prove there isn't. That's trying to prove a negative.

In your example, you have proven that some average survival time of your rats is 2.5hrs. That's a positive.

• #### Re:Zero warning (Score:5, Informative)

on Sunday December 27, 2009 @05:01PM (#30565922)

It doesn't sound like anything is proven, or else it would be "case closed".

Wikipedia is not authoritative. Neutrinos have been known to have mass for over five years now, and the physics community is now focused on refining the parameters that characterize massive neutrinos. [queensu.ca]

Although we know that neutrinos have mass, we don't know what the mass is because our current experiments are only sensitive to the square of the mass difference between different types of neutrino. However, we do know that all types of neutrino have mass, although the most plausible values are less than a millionth of the electron mass, making it tricky to detect by time-of-flight measurements because any detectable neutrino is going to be ultra-relativistic, travelling so close to the speed of light as to be indistinguishable from a massless particle under almost all circumstances, which is why it was so difficult to prove they do have mass.

• #### Re:Was there anyone in space that day? (Score:3, Informative)

on Sunday December 27, 2009 @05:04PM (#30565950)

Phil says further down in the comments that the ISS was behind the earth when the main pulse hit.
If it had been in front, the astronauts would have gotten the equivalent of a dental X-ray.

• #### Re:Blasted Whom? (Score:2, Informative)

by Anonymous Coward on Sunday December 27, 2009 @11:08PM (#30568206)

That's an interesting question.

I did some quick calculations, and it appears that the blast was "above" 23.28 degrees S and 142.13 degrees W. This is over ocean, but Tahiti (and other islands) are nearby.

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