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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!"
When gamma ray detectors were first put on satellites (to detect nuclear bombs being detonated on Earth) huge gamma ray bursts were found coming from around the universe. I don't think we have ever explained what causes them but they are even more energetic than supernova. Would this even be a possible candiate for the cause of such bursts? Or is it not energetic enough? The current popular explaination is these bursts are black holes being born. Can any astronomers here to explain this to a humble programmer?
"Those that start by burning books, will end by burning men."
"Had this happened within 10 light-years of us, it would have severely damaged our atmosphere and possibly have triggered a mass extinction," said Bryan Gaensler of the Harvard-Smithsonian Center for Astrophysics (CfA). Just yesterday I was looking through a link from a /. article in May; while the solar wind is usually strong enough to push off the interstellar wind (think of it as the sum of solar winds from the rest of the galaxy) at a distance 94 times that of the distance from the Sun to Earth.
What's significantly impressive is that this explosion is strong enough to kick nearly multiple times as hard as the average of what the galaxy usually does to us.
(I'm not quite sure on this figure - the power of the wind from our sun should decrease as r^3, ditto the power from the starquake; if r goes down to 1/94, r^3 is reaching for a million?! This would imply the quake is nearly a million times as strong as the average wind from the galaxy; granted there's likely to be drastic fluid dynamics contortions and things that effectively cut that number down to something more 'sane' (depending on how sane you think it is to try to calculate stellar force magnitudes...), but you still have a figure significantly bigger than the entire galaxy!)
And then you get to the quote line from the article "We have observed an object only 20 kilometers across [12 miles], on the other side of our galaxy, releasing more energy in a tenth of a second than the Sun emits in 100,000 years."
combine that with the distance from us (50000 light years = 6 trillion miles = 10 trillion km) and the bit where it says it rotates on its axis every 7.5 seconds and has the strongest magnetic field in the known universe... wow.
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
Sincerely
M' uldh pGar
Chief of PR Intergalactic Council
Searching Google for phrases from that post didn't turn up ANY hits, so it doesn't seem to be a cut-and-paste troll.
Subject: Cracks me up (31 August 2005)
"Of course they're baffled. They won't let anybody competent explain it to them. These guys never studied plasma fluid dynamics in school, and they figure that now they're too old to learn it."
Subject: Re:Galaxies must be a lot more dynamic than I thou (3 September 2005)
"The reason they insist it has to be something spinning is that they have studied almost no plasma fluid dynamics, so they can't understand something blasting out radio, light, and x-rays that doesn't have a star in the middle of it."
etc etc
He's not a cut and paste troll, but he's posted enough similar things in the past that I thought the same thing as the GP when I read this one.
"...always new atoms but always doing the same dance, remembering what the dance was yesterday." -Richard Feynman
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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From TFA:Ok, so a magnetar is a type of neutron star with an extremely strong magnetic field. Also from TFA:So, is it a neutron stat or not? I was under the impression that neutron stars were called that because the immense gravitational field squished all the protons and electrons together into neutrons, forming an all-neutron star. It would seem that Wikipedia's definition supports the idea of a non-homogeneous neutron composition. When did it change from being all-neutrons to having a yummy mostly-neutrony center?
Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
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
Replying to trolls is usually a mistake, but fine:
It's not hard to measure astronomical electrical currents: electrical current is directly proportional to magnetic field strength, which is routinely measured using the Zeeman effect. Yes, any place you find a magnetic field, electric charges are in motion. No, the interior of a rotating star is not the only place where charged particles can move.It's not clear that interstellar currents produce much of the sun's light. (It would account for events at the sun surface that core fusion cannot, but the evidence is incomplete.) What is perfectly clear is that they power x-ray emissions of similar magnitudes distributed across light-years-wide nebulae. Any description of a celestial phenomenon where they are known to occur (e.g. where there is a visible "jet", or x-rays over an extended region) that neglects them, and also fails to explain why their effects must be negligible, is trivially wrong. Any model of galactic or cosmic evolution that fails to reproduce them is, likewise, trivially wrong.
People who take dark matter and dark energy seriously obviously aren't very interested in "convincing evidence", because they have exactly none at all. (Not only that, there's no place to put it: galactic lensing analyses show galaxies are no more massive than the stars and dust in 'em.) The only properties either has is whatever mass or repulsion is needed to prop up a falsified cosmogological theory -- and a different amount for each theory.
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.