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'Starquake' Cracks Star
geekroot's dad writes "Space.com is reporting that a huge 'starquake' releasing as much energy as our sun does in 250,000 years, has cracked a nearby neutron star. The magnetar produced the brightest explosion ever seen by man outside of the milky way. Although it is 50,000 light-years away, the blast was so huge it temporarily blinded some satellites and briefly altered Earth's upper atmosphere!"
Okay, Yikes. Missed this the first time round:
Of the known magnetars, four are called soft gamma repeaters, or SGRs, because they flare up randomly and release gamma rays. The flare on SGR 1806-20 unleashed about 10,000 trillion trillion trillion watts of power.
10 000 000 000 000 000 000 000 000 000 000 000 000 000 000 watts of power. No wonder my brain gave up trying to work out the numbers.
Browsing with +2 to insightful posts and a higher threshold makes the average post seen seem a lot more ingenious
I agree that in general it's not that simple: gravity pulls the wind back, so that it falls off faster than that, but with a "quake" like this, gravity's going to have a hard job.
Wikileaks, no DNS
You are thinking of Gamma Ray Bursts (GRBs). They are actually much MORE violent events than this one, but also MUCH further away.
They are still being studied, and their causes are still somewhat ambiguous, but black holes are almost certainly involved. One theory, if I recall correctly is big bright short-lived stars in the early universse reaching the end of their life. The core of the star then collapses very suddenly, forming a black hole (in a regular supernova you get a neutron star) and the outer part of the star follows it in, and get heated and churned by the implosion, and then explodes out. Another theory is that a GRB represents the last moments a a neutron star falling into a black hole, or two neutron stars colliding to form a black hole.
These magnetar related events are much less energetic, but loads nearer.
No. Pulsars flash regularly, but mainly radiate at optical and radio frequencies. They are pretty surely neutron stars and relatively nearby (within a few thousand light years). Gamma Ray Bursts are one-off events, probably very far away (billions of light years) and radiate mainly gamma rays. We are less sure what they are, but it's something VERY violent.
The original topic. magnetars. are actually in between. They radiate pulses of lower energy gamma rays that repeat irregularly. We think they are highly magnetic neutron stars tens of thousands of light years away, that undergo very violent "starquakes" from time to time.
Interestingly enough, a physicist by the name of Robert Forward (did alot of work with space tethers) published a book called Dragons Egg about life on a neutron star. He actually said it was really a book on neutron star physics described as a science fiction book. Anyways the sequel to it was called Starquake where exactly this happened. Both books were interesting reads, and although this is kind of off topic, it just reminded me of them.
History will be kind to me, for I intend to write it - Sir Winston Churchill
A million is 1000^2 or 10^6, .... ....
..
a billion is 1000^3 or 10^9,
a trillion is 1000^4 or 10^12,
a quadrillion is 1000^5 or 10^15
a quintillion is 1000^6 or 10^18
a sextillion is 1000^7 or 10^21
a septillion is 1000^8 or 10^24
a octillion is 1000^9 or 10^27
a nonillion is 1000^11 or 10^30
a decillion is 1000^12 or 10^33
a undecillion is 1000^13 or 10^36
a duodecillion is 1000^14 or 10^39
a tredecillion is 1000^15 or 10^40
a quattuordecillion is 1000^16 or 10^42
a quindecillion is 1000^17 or 10^45
a sexdecillion is 1000^18 or 10^48
a septendecillion is 1000^19 or 10^51
a octodecillion is 1000^20 or 10^54
a novemdecillion is 1000^21 or 10^57
a vigintillion is 1000^22 or 10^60
a zillion is 10^playground
a googol is 10^100
a googolplex is 10^googol (if you wrote this down in its expanded form, the paper would not fit into the volume of the solar system)
So the wattage output of the SGR 1806-20 flare is just a piddly 1.0 tredecillion watts - or, you you adopt Jim Blower's Extended System of Units, that would be 10 tredawatts
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The physics used to keep a human-crewed spaceship in close orbit around a neutron star without tidal forces ripping the crew apart are interesting. The appendicies to "Dragon's Egg" have interesting "hard" (well, not really: high school physics should be enough to understand them) derivations.
You could've hired me.
Um...they're called Birkeland currents.
http://en.wikipedia.org/wiki/Birkeland_current
kthxbye
Luckily, it's NOT a magnetar. One of those 200 ly away would be serious cause for concern.
l which does a good job of explaining the physics in non-technical terms.
There's a good site at http://solomon.as.utexas.edu/~duncan/magnetar.htm
It seems that neutron stars are born on a cusp. If they're spinning fast enough, a self-sustaining dynamo process, similar to that in the Earth's core starts up in the first few milliseconds of it's life. Within a few seconds, energy from the initial immense heat of the star is siphoned off to increase the (already huge) magnetic field by hundreds or thousands of times, and this field is then locked in place as the star cools.