How powerful are gamma bursts?

Bertie Wooster · Post by **Bertie Wooster** » 2005-09-13 03:07pm

Specifically, how much energy is released in gamma-bursts some of which are supposed to be the most powerful explosions in the universe since the big bang?

THe only thing I was able to find in terms of an energy emission is that more energy is released in a 1/10 of a second gamma burst than our sun releases energy in its entire lifetime, some of which rival or surpass the amount of energy released by supernovas.

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dragon · Post by **dragon** » 2005-09-13 03:15pm

Well gamma burst can be fairly small they some have been detected on earth as for the big ones. The biggest one record had the power of 10 billion million suns, their words not mine.

This particular burst had the power of nearly ten million billion suns, and the light grew so bright that anyone gazing at the night sky could have seen it using only a pair of binoculars

http://science.nasa.gov/newhome/headlin ... an99_1.htm

dragon · Post by **dragon** » 2005-09-13 03:16pm

dang ment to hit preview messed up on the wording.

dragon · Post by **dragon** » 2005-09-13 03:22pm

Ok the power output of the sun is 4*10^26 watts.

http://www.cbu.edu/~jholmes/N111/Part23/sld018.htm

Since I have been up almost 30 hours i will let you do the math.

aerius · Post by **aerius** » 2005-09-13 03:30pm

According to a Scientific American issue I have, a gamma ray burst will release about 10^45 to 10^47 joules.

SyntaxVorlon · Post by **SyntaxVorlon** » 2005-09-13 06:02pm

It's the original fuckton energy explosion.

Bertie Wooster · Post by **Bertie Wooster** » 2005-09-13 07:22pm

aerius wrote:According to a Scientific American issue I have, a gamma ray burst will release about 10^45 to 10^47 joules.

hmmm, 23.9 trillion yottatons.

wolveraptor · Post by **wolveraptor** » 2005-09-13 07:49pm

There must be some statistics on how many years that kind of energy would sustain Earth (assuming complete technological stagnation, unless you can account for that too).

kheegster · Post by **kheegster** » 2005-09-13 07:55pm

wolveraptor wrote:There must be some statistics on how many years that kind of energy would sustain Earth (assuming complete technological stagnation, unless you can account for that too).

10^46 Joules of energy is more than what our Sun releases over its entire lifetime (10^17 seconds multiplied by the solar luminosity, 10^26 J /second = 10^43 J). Considering that we currently consume far less power than the Sun produces....

Of course, if you're anywhere near a couple of hundred parsecs of a GRB, you'd be fried within a few hundred years of the GRB occuring.

Duckie · Post by **Duckie** » 2005-09-13 08:01pm

wolveraptor wrote:There must be some statistics on how many years that kind of energy would sustain Earth (assuming complete technological stagnation, unless you can account for that too).

Wikipedia:
In 2001, energy use was 4.26*10^20 J.
A Gamma Burst does 10^47 J.

So, 10^47/[4.26*10^20]= 234,741,784,000,000,000,000,000,000?

2.35*10^23 Years? That's a lot, if I did the "plug into google calculator" right. Don't count on that.

Duckie · Post by **Duckie** » 2005-09-13 08:06pm

Ghetto Edit

2.35*10^26 Years. Screwed up my Scientific Notation.
That's long enough, that assuming 100% Energy Efficiency in converting it, the power would last long enough to cease galaxy/star formation, and watch the stars fling planets from their orbits and get flung out of galaxies themselves by gravity perturbations according to Wikipedia.
It's also within 10^10 years of Proton Decay, if that is a correct hypothesis.

Admiral Valdemar · Post by **Admiral Valdemar** » 2005-09-13 08:30pm

Even if nucleons like protons do decay, we'll have bigger problems to contend with before even that comes up, nevermind using all that raw energy. It seriously makes something like a planet busting blast look wholly pathetic.

Duckie · Post by **Duckie** » 2005-09-13 09:09pm

Admiral Valdemar wrote:Even if nucleons like protons do decay, we'll have bigger problems to contend with before even that comes up, nevermind using all that raw energy. It seriously makes something like a planet busting blast look wholly pathetic.

I was speaking hypothetically, assuming we had a black box that converts 100% of the gamma burst to electricity and that the Earth is not affected by universal events.

To speak more realistically, a fraction of a fraction of a fraction of a fraction of that energy from the Black Box would run our planet till the Sun dies.

Admiral Valdemar · Post by **Admiral Valdemar** » 2005-09-13 09:15pm

That's a fair few Duracells then.

Noble Ire · Post by **Noble Ire** » 2005-09-13 09:35pm

Using Wikipedia's estimation of the world's energy consumption in 2001, the time works out to something like 7.4074x10^28 years.

My calculations are probably way off though.
(Wikipedia lists the 2001 power consumption at 13.5 terawatts.)

Noble Ire · Post by **Noble Ire** » 2005-09-13 09:37pm

Edit: That's total power consumption, not electrical.
http://en.wikipedia.org/wiki/Terawatt#Terawatt

Duckie · Post by **Duckie** » 2005-09-13 09:41pm

Noble Ire wrote:Edit: That's total power consumption, not electrical.
http://en.wikipedia.org/wiki/Terawatt#Terawatt

I'm an idiot at science beyond "Don't Mix Ammonia and Bleach", but how did you get the Power for a Gamma Burst? Assume the Magic Black Box takes only a second to generate its power, making it 10^47 Watts?

Or am I completely forgetting something?

Noble Ire · Post by **Noble Ire** » 2005-09-13 10:22pm

MRDOD wrote:
Noble Ire wrote:Edit: That's total power consumption, not electrical.
http://en.wikipedia.org/wiki/Terawatt#Terawatt
I'm an idiot at science beyond "Don't Mix Ammonia and Bleach", but how did you get the Power for a Gamma Burst? Assume the Magic Black Box takes only a second to generate its power, making it 10^47 Watts?

Or am I completely forgetting something?

I'm not really a science pro either, I just applied the figures I found on Wikipedia to one another.

Duckie · Post by **Duckie** » 2005-09-13 10:25pm

Noble Ire wrote: I'm not really a science pro either, I just applied the figures I found on Wikipedia to one another.

I think I might be correct then, because you applied the "Watts" figure for Gamma Bursts, right? That's the luminosity of the Burst (which is nearly the rest of the universe's brightness combined, in an interesting fact), not the total energy thrown off.

Wouldn't you end up with Luminosity Per Watts [Luminous Efficacy?] or some irrelated unit if you did that?

Kuroneko · Post by **Kuroneko** » 2005-09-13 10:38pm

MRDOD, you did it correctly the first time around. Instead of attempting to find the gamma ray burst's luminosity, figure out the world's yearly energy consumption instead. The world's energy consumption in 2001, if the 13.5TW average figure is correct, is (13.5e12J/s)*(365.24*24*3600s/yr) = 4.26e20J/yr. This is precisely your figure. Assuming a gamma ray burst of order between 1e44 and 1e48 joules (GRB990123 was 4e47J), the Earth could be powered at 2001 level between 1e23 and 1e27 years. At 4e47J, 9e26 years.

Duckie · Post by **Duckie** » 2005-09-13 10:46pm

Kuroneko wrote:MRDOD, you did it correctly the first time around.

Ah, good. I had assumed so.

The main thing I've heard about Gamma Bursts is that a close proximity burst would destroy most of a Galaxy (either physically or wiping out all life through Gamma Radiation, I forget which). Is that accurate? The neighborhood of 2E47 Joules from an explosion glowing a hundred times brighter than the galaxy itself does sound rather scary. What are the odds of it occuring?

wolveraptor · Post by **wolveraptor** » 2005-09-14 12:13am

So essentially, even if we were at a Star Warsian level of development, it'd still be enough for billions of years.

ClaysGhost · Post by **ClaysGhost** » 2005-09-14 04:42am

MRDOD wrote: The main thing I've heard about Gamma Bursts is that a close proximity burst would destroy most of a Galaxy (either physically or wiping out all life through Gamma Radiation, I forget which). Is that accurate?

I think some team showed that the nearest likely candidate for a hypernova, Eta Carinae, would be unable to do much damage (beyond frying some satellites on the side of the planet affected by the blast). I don't know, it seems to me that even if these things aren't beamed they'd pose a significant radiation risk to biological systems. But the consensus seems to be that all the ones that could hurt us have already gone off. Certainly, the extremely bright GRBs all seem to be at cosmological distances, high hundreds to billions of parsecs away.

kheegster · Post by **kheegster** » 2005-09-14 07:29pm

ClaysGhost wrote:
MRDOD wrote: The main thing I've heard about Gamma Bursts is that a close proximity burst would destroy most of a Galaxy (either physically or wiping out all life through Gamma Radiation, I forget which). Is that accurate?
I think some team showed that the nearest likely candidate for a hypernova, Eta Carinae, would be unable to do much damage (beyond frying some satellites on the side of the planet affected by the blast). I don't know, it seems to me that even if these things aren't beamed they'd pose a significant radiation risk to biological systems. But the consensus seems to be that all the ones that could hurt us have already gone off. Certainly, the extremely bright GRBs all seem to be at cosmological distances, high hundreds to billions of parsecs away.

The closest GRB I've heard of had a redshift of about 0.01, which translates to a distance on the order of 10^8 parsecs..

wolveraptor · Post by **wolveraptor** » 2005-09-14 10:24pm

Hmm. An above link says the source of gamma ray bursts is unknown. Doesn't it occur when two neutron stars collide?