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Milky Way's Black Hole a Gamma Source?

kdawson posted more than 7 years ago | from the high-energy-pinball dept.

Space 100

eldavojohn writes "A paper recently accepted for publication (preprint here) proposes a sound explanation for the source of the gamma rays that permeate our galaxy. The Milky Way's central object Sagittarius A*, widely believed to be a supermassive black hole, is now suspected to be the source. To test this theory, two scientists created a computer model to track the protons, flung outward with energies up to 100 TeV by the intense magnetic fields near the event horizon, as they make a random walk through the plasma environment. It can take thousands of years for them to travel 10 light-years from the black hole, where they collide with lower-energy protons to form pions. These decay into gamma radiation emanating from a torus-shaped region around the central object."

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Suggested tag (1)

Kelz (611260) | more than 7 years ago | (#18254694)

Hulk!

Brings to mind this question .... (4, Funny)

Archangel Michael (180766) | more than 7 years ago | (#18254724)

"The Milky Way's central object Sagittarius A* [CC], widely believed to be a supermassive black hole, is now suspected to be the source."

Would that make it an "A-Hole" ?????

Re:Brings to mind this question .... (4, Funny)

PhrostyMcByte (589271) | more than 7 years ago | (#18254870)

Coming from Sagittarius A*, the gamma radiation will obviously have little difficulty finding a path to earth.

Re:Brings to mind this question .... (1)

pclminion (145572) | more than 7 years ago | (#18255572)

How many others got that one? ;-) I salute you!

Re:Brings to mind this question .... (1)

RxScram (948658) | more than 7 years ago | (#18256094)

I had to read it twice, but I got it... well done!

Re:Brings to mind this question .... (1)

Tim C (15259) | more than 7 years ago | (#18256410)

I got it, but would I have if you hadn't asked? (Mind you, he did bold it...)

Re:Brings to mind this question .... (0)

Anonymous Coward | more than 7 years ago | (#18255882)

Would someone please explain why parent is modded funny?

Re:Brings to mind this question .... (5, Informative)

PhrostyMcByte (589271) | more than 7 years ago | (#18255940)

Would someone please explain why parent is modded funny?

A* [wikipedia.org] is a path finding algorithm. It is used in many games, such as Starcraft.

Re:Brings to mind this question .... (1)

TheThiefMaster (992038) | more than 7 years ago | (#18260144)

It's also a pain to find information on using a search engine. Both "A*" and "A-Star" return completely unrelated results in google. I used to have problems searching for C++ as well, but I'm not sure that wasn't an ie bug (all spaces in the search are submitted as +s, but the +s weren't url-encoded so google decoded the query as C-space-space)

Re:Brings to mind this question .... (1)

biovoid (785377) | more than 7 years ago | (#18273150)

a star pathfinding [google.com] .

Re:Brings to mind this question .... (1)

Chysn (898420) | more than 7 years ago | (#18263058)

> > > Coming from Sagittarius A*, the gamma radiation will obviously have little difficulty finding a path to earth.

> > Would someone please explain why parent is modded funny?

> A* is a path finding algorithm. It is used in many games, such as Starcraft.

        Ah, I see now. It's still not very funny.

Re:Brings to mind this question .... (0)

Anonymous Coward | more than 7 years ago | (#18257146)

Wow, that's possibly the most well-deserved "+5, Funny" I've ever seen on Slashdot. Nerd wit at its finest.

Re:Brings to mind this question .... (1)

Assassin bug (835070) | more than 7 years ago | (#18257794)

Read the quoted text again... This time with a Barry White [wikipedia.org] dramatization.
Disturbing...very disturbing..

Re:Brings to mind this question .... (0)

EinZweiDrei (955497) | more than 7 years ago | (#18254990)

Gamma a break.

Re:Brings to mind this question .... (3, Funny)

slashgimp (513115) | more than 7 years ago | (#18255004)

I sense an oncoming joke about Administratium, what with all the talk of A-holes, peons, and things taking thousands of years to accomplish a task ;)

Whee!

Re:Brings to mind this question .... (2, Funny)

Hoi Polloi (522990) | more than 7 years ago | (#18256042)

I always thought the Milky Way was full of yummy nougat. Ummmmm....nougat

And about Gamma Rays... (0, Offtopic)

mangu (126918) | more than 7 years ago | (#18257204)

What does the Gay Married Men Association [swbell.net] have to do with this A*-hole? Oh, wait, never mind...

Re:Brings to mind this question .... (1)

inviolet (797804) | more than 7 years ago | (#18258554)

Would that make it an "A-Hole" ?????

Darth Helmet: "How many assholes we got in this galaxy anyway?!"
Sagittarius A: "Yo!"
Darth Helmet: "I knew it -- I'm orbiting an asshole!"

Zodiac? (0, Offtopic)

zoloto (586738) | more than 7 years ago | (#18254728)

I always knew I was more powerful because of my astrological sign. Now I have proof!
Or proof that my life sucks... either way, it's something!

Re:Zodiac? (1)

kan0r (805166) | more than 7 years ago | (#18259304)

Interesting. It is something, good or bad doesn't matter really. All that matters is that there is a connection somehow. This actually seems to be enough to satisfy something in here, something that is bored a bit. I am of the same astrological sign, by the way.

Re:Zodiac? (0)

Anonymous Coward | more than 7 years ago | (#18265694)

It proves that at the center of your life, like mine, is a big, sucking hole.

Black Hole (2, Funny)

alexj33 (968322) | more than 7 years ago | (#18254750)

The Milky Way's central object Sagittarius A*, widely believed to be a supermassive black hole, is now suspected to be the source.

That black hole must really suck.

Re:Black Hole (0, Funny)

Anonymous Coward | more than 7 years ago | (#18255504)

Recent evidence now suggests the supermassive black hole was created when Chuck Norris punched Superman so hard he ripped a hole in the fabric of space.

Paging Louis Wu (4, Funny)

sqlrob (173498) | more than 7 years ago | (#18254764)

Long Shot is ready for departure

Re:Paging Louis Wu (2, Funny)

j_presper_eckert (617907) | more than 7 years ago | (#18255762)

God, how I love the concept of the "Long Shot". 75 seconds to the light-year [-swoon-].

Imagine a Beowulf Shaeffer cluster of those...

Thanks folks, I'll be here all week. Be sure to tip your Puppeteer generously!

Re:Paging Teela Brown (2, Funny)

savage1r (856578) | more than 7 years ago | (#18258374)

Get ready to recieve my Hot Needle of Inquiry.

Re:Paging Louis Wu (1)

CRCulver (715279) | more than 7 years ago | (#18260632)

The Larry Niven short story where the galactic core was explored was "At the Core" (now collected in Crashlander [amazon.com] ). That was a Beowulf Shaeffer story, not a Louis Wu one. And, of course, Niven's vision of the galactic core--just lots of densely packed stars--is superseded by the current speculation that it's a black hole.

Re:Paging Louis Wu (1)

Agripa (139780) | more than 7 years ago | (#18264974)

Niven's short story "Rammer" which later became the novel "A World Out of Time" featured a galactic sized black hole at the center of the milky way . Admittedly, this was 10 years after "At the Core".

Sagittarius A (1)

Ramble (940291) | more than 7 years ago | (#18254772)

That's no black hole!

Source... (-1, Offtopic)

Anonymous Coward | more than 7 years ago | (#18254796)

It might be the source of gamma radiation but it sure as hell ain't a good source of calcium.

huh? (1, Interesting)

mastershake_phd (1050150) | more than 7 years ago | (#18254832)

I thought the background gamma radiation was from the big bang and thus older than the galaxies?

Re:huh? (0)

Anonymous Coward | more than 7 years ago | (#18254860)

Obviously you thought wrong.

Re:huh? (4, Informative)

spun (1352) | more than 7 years ago | (#18254868)

You're thinking of microwave radiation.

Re:huh? (4, Funny)

StikyPad (445176) | more than 7 years ago | (#18256856)

Well now I'm thinking of heating up a frozen BBQ sandwich. Thanks.

Re:huh? (1)

Normal Dan (1053064) | more than 7 years ago | (#18254946)

There is some background radiation thought to have come from the big bang. However, there is also something called a gamma ray burst. These bursts are far too powerful to be remnants of an ancient explosion. I on the other hand thought they found these gamma ray bursts to be originating from far away galaxies. Maybe there is something I am missing?

Re:huh? (1)

MindStalker (22827) | more than 7 years ago | (#18255218)

Both, many blackholes release gamma ray burst in streams which travel very long distances. Apparently our galactic center also releases gamma rays. If you read the article the Slashdot summary doesn't even seem to come from it, the article is about a computer model of Sagittarius A confirming this predicted action.

Distribution of life? (3, Interesting)

PIPBoy3000 (619296) | more than 7 years ago | (#18254838)

I wonder if that means that life is only possible near the outer arms of the galaxy? If you assume that gamma rays are a point source in the middle of our galaxy, what sort of radiation levels are you going to see closer to the center?

Re:Distribution of life? (5, Interesting)

Normal Dan (1053064) | more than 7 years ago | (#18255078)

There are already dangerous levels of radiation within our own solar system, however, we are protected by an atmosphere. I would imagine one of two possibilities. Any planet with the potential for life closer to the center of our galaxy would have enough shielding of some sort (either a thick atmosphere or a thick ocean) to allow life to form on almost any suitable location in the galaxy. The other possibility is, life can exist in high amounts of radiation, but it might not be life as we know it.

Re:Distribution of life? (4, Interesting)

Dan Slotman (974474) | more than 7 years ago | (#18255582)

Actually, other parts of the galaxy are farther from the milky way and other black holes. These arms, teeming with life, use gamma rays to communicate and travel. They haven't come calling since our arm is poisoned with radiation, making interstellar travel prohibitively dangerous!

High Radiation Life Forms (2, Interesting)

Lord Balto (973273) | more than 7 years ago | (#18255598)

Of course. Life evolves to fit the current conditions. In a high radiation environment, I can imagine a life form that takes advantage of the high radiation levels to rapidly mutate and evolve, increasing its chances of survival in a hazardous environment. Actually, there are plants on this very planet that for some reason have developed the abilty to mutate rapidly. The hawthorn for example. There was a point when there were hundreds of named species of hawthorn. Before the botanists realized the damned things were just mutating spontaneously.

Re:High Radiation Life Forms (1)

Eddu (999813) | more than 7 years ago | (#18257220)

You know that's nice, but what's their IQ? IMO it's highly improbable that intelligent races evolve in unstable or high radiation environments. High radiation destroys DNA and well - unstable environments just kill so fast that it's not better to have brains instead of a thick shell or high reproduction

Re:High Radiation Life Forms (1)

Magada (741361) | more than 7 years ago | (#18260002)

We have some evidence that complex organisms evolve from colonies (most likely, simbyotic colonies) of simpler organisms. What if these hard-shelled, fast-breeding things work out a way to stick together and work as a whole?

Re:High Radiation Life Forms (1)

Lord Balto (973273) | more than 7 years ago | (#18293506)

Actually, it seems to me that intelligence would be likely to evolve more rapidly in a rapidly evolving biosystem. And once it arose, you'd have a much broader range of implimentations of that intelligence, including such specialized abilities as telepathy and telekinesis. Also, one would expect that there would be rapid evolution in such an environment of mechanisms that protected certain parts of the genetic material, either through redundancy or through dynamic reconfiguration.

Water Bears (3, Informative)

Neutrino Linguino (1072502) | more than 7 years ago | (#18255634)

Tardigrades [aka Water Bears], which live everywhere on this planet Earth, can...
1) resist storage in liquid nitrogen
2) survive in contact with mineral acids, organic solvents, and boiling water
3) survive in a a vacuum and under high pressure
4) withstand ionizing radiation of over 600,000 roentgens (500 roentgens would be fatal to a human)

Re:Water Bears (2, Interesting)

khallow (566160) | more than 7 years ago | (#18257134)

Hmmm, you got to wonder if that's a fortuitous coincidence or if that amazing ability to survive was spurred by something in their environment. Now that I think of it, any organism that can exist in an indefinite "cryptobiosis" [wikipedia.org] state (ie, when all metabolic processes stop for a possibly long period of time) would do better if it had some of the above properties. In particular, the ability to survive extreme genetic damage is necessary IMHO. Suppose humans had similar abilities. If I entered cryptobiosis say in an "average" North American location, I'd receive a whole body dose of perhaps 3 millisievert per year (maybe much less since I'm no longer breathing carbon 14 and radon). Since I'm in cryptobiosis, I have no ability to repair radiation damage, it's like I experience this huge pulse of radiation damage.

According to here [uic.com.au] , every 100 millisievert results in a 5% boost (supposedly) in average life-time cancer rates, and 1000 or more millisievert is life threatening. So 30-40 years gives me a 5% boost in cancer rates and 300-400 years of cryptobiosis gets me up to 1000 millisievert. I can't survive roughly 3000 or more years (10 sievert which is automatically lethal) because I literally receive a fatal dose of radiation before I have a chance to repair it. We ignore that there may be other ionizing processes (chemical or thermal, for example) that would vastly shorten this time.

Re:Water Bears (1)

Dan Hayes (212400) | more than 7 years ago | (#18260402)

Water bears really do rock - crazy tough little buggers! Fire a few into space, and they'd be ready to wake up whenever they hit water ;)

Re:Distribution of life? (1)

Kyeetza (927172) | more than 7 years ago | (#18256146)

.....The other possibility is, life can exist in high amounts of radiation, but it might not be life as we know it.
I've always been curious about other kinds of life. With all the complexity that exists, it seems naive to think that DNA is the only kind of self replicating molecule in the universe......

Re:Distribution of life? (1)

khallow (566160) | more than 7 years ago | (#18256898)

Or that we're the only way that DNA-based life could evolve.

Re:Distribution of life? (2, Interesting)

Artifakt (700173) | more than 7 years ago | (#18257938)

There are definitely at lest one other self replicating molecule already known (RNA). RNA however has a much higner rate of copying errors, and lower error rates actually promote selection (down to a minimum - obviously zero errors means no selection at all, but even DNA is somewhere still well above the calculated ideal error rate for fastest selection).
        This seems somewhat counter-intuitive, but if you think of a species as a set with somewhat fuzzy boundaries, more errors mean the boundaries are fuzzier. More members of a species deviate farther from the average type. Since enough members of a species usually survive long enough that the avaerage organism reproduces once, most members are already pretty well adapted to their niche. Higher mutation rates therefore mean more members are ill adapted, so selection actually slows down because more species get out of balance and die out faster and more often without leaving a successor species. A higher mutation rate also means more organisms have 2 or more mutations, and since most mutations are negative, a swamping effect occurs, where possibly good mutations don't ever get a chance to be selected. A really high mutation rate means genes don't just find themselves increasingly surrounded by defective partner genes, they actually get a chance of being overwritten before they linger for enough generations to be tested.
        For sexually reproducing species, the chance of not being able to successfully breed with a given other goes up very quickly, etc, so sex becomes a less successful option than parthenogenesis, etc, and again selection slows down even more.
        Most biologists think RNA was once dominant on our planet, and that there were other replicators, more primative and having higher error rates, before RNA. It's possible that some of these are more optimal under other conditions, i.e. more or less radiation, heat, or in other atmospheres. It's also possible some codes that were never developed here on Earth have developed in other places.

Re:Distribution of life? (1)

mdielmann (514750) | more than 7 years ago | (#18262308)

There are already dangerous levels of radiation within our own solar system, however, we are protected by an atmosphere.
No, we're protected by a magnetosphere. It deflects solar wind and, I'd assume, other charged particles that are sleeting our planet. Mars [nasa.gov] has no such magnetosphere (and not much of an atmosphere, either - not entirely unrelated), and radiation is a real problem there.

Re:Distribution of life? (1)

physicsboy500 (645835) | more than 7 years ago | (#18255136)

I wonder if that means that life is only possible near the outer arms of the galaxy? If you assume that gamma rays are a point source in the middle of our galaxy, what sort of radiation levels are you going to see closer to the center?

Regardless I don't think the space tollway is going to be built anytime soon so...

DON'T PANIC

Re:Distribution of life? (2, Interesting)

MollyB (162595) | more than 7 years ago | (#18255372)

I'm no scientist, but as amateur astronomer and cosmology 'nut' I can say that even though the central portion (the "bulge") may have higher levels of radiation of all frequencies that would be damaging to life-as-we-know-it, the fact remains that out in the spiral arms of the galaxy there are many stellar nursuries (huge molecular clouds that occasionally have a shock wave pass through that can ignite new stars). These regions sometimes congeal a massive star which burns in a few millions of years rather than the multi-billion life our sun can expect. This star then explodes quite violently, and fries the surrounding neighboorhood, not only with electromagnetic radiation of many frequencies (gamma included), but would bombard nearby star systems with ionizing radiation (unhealthy stuff like the nuclei of iron, etc.) even if it is in the galactic suburbs.
So, maybe it is lucky it'd take about 30,000 years at the speed of light to get to the center; it is dangerous enough way out here, nevermind the comets and asteroids. 8)

Re:Distribution of life? (1)

iago-vL (760581) | more than 7 years ago | (#18255512)

Don't forget about Sha Ka Ree [wikipedia.org] . It's at the centre of our galaxy and the crew of the Enterprise seemed all right...

Re:Distribution of life? (1)

jwiegley (520444) | more than 7 years ago | (#18256156)

What??? We're not the center of the galaxy??? Somebody better tell God, 'cause he's gonna be pissed!!

oblig. (2, Funny)

Rob T Firefly (844560) | more than 7 years ago | (#18254852)

What does God need with a starship?

Re:oblig. (1)

mikael (484) | more than 7 years ago | (#18255354)

A tax deductible expense...

Re:oblig. (1)

iago-vL (760581) | more than 7 years ago | (#18255538)

Haha, I just read that when I went to look up the name of Sha Ka Ree. Turns out, you were way ahead of me :(

Do we know? (2, Interesting)

pygmy_jesus (1071948) | more than 7 years ago | (#18254864)

I've been semi-interested in Cosmology/Astrophysics lately, and from everything I've seen and read so far, I've ascertained that we don't know much. Between dark matter, dark energy, gravity, black holes, big bang, etc. it seems like we just conveniently make up "stuff" to fit some model or equation. Do discoveries like this mean anything at this time considering there's no way to prove any of it?

Re:Do we know? (1, Funny)

IflyRC (956454) | more than 7 years ago | (#18254960)

Between dark matter, dark energy, gravity, black holes, big bang, etc. it seems like we just conveniently make up "stuff" to fit some model or equation.

Is that not the same statement many have made as to the reason man in early history believed in gods?

That black hole is angry, its throwing things at us!

Re:Do we know? (5, Insightful)

MightyMartian (840721) | more than 7 years ago | (#18254984)

I've been semi-interested in Cosmology/Astrophysics lately, and from everything I've seen and read so far, I've ascertained that we don't know much. Between dark matter, dark energy, gravity, black holes, big bang, etc. it seems like we just conveniently make up "stuff" to fit some model or equation. Do discoveries like this mean anything at this time considering there's no way to prove any of it?
Translation: I know the names of some scientific fields, but never read more than the science headlines in the newspaper. Clearly this is the fault of scientists.

Re:Do we know? (3, Insightful)

Ibag (101144) | more than 7 years ago | (#18255776)

While this probably is an accurate translation, GP has a point. A lot of science can seem rather ad hoc at times. Before we had discovered all the planets, scientists noted that the orbits of the known planets were not quite what they should be. Instead of declare that newton's theory of gravity was wrong, they theorized that there was an unknown planet. After doing some calculations, they determined where this planet had to be, looked up at the sky, and found Neptune.

Similarly, when cosmologists look at the apparent rate of expansion of the universe (and how that rate has changed over time), they get that if their model of the way things work (general relativity) is correct, then their estimates of the mass in the universe based on empirical observation cannot possibly be right. Instead of abandoning relativity and leaving a void in its place, they say, "This will work of there is a large amount of matter that we can't observe. Dark matter!" Of course, this doesn't resolve everything, and we need various other adjustments (like dark energy, or physical constants that aren't constant) which look like kludges, but which have predictive power and are the best answers we've got.

Do we "know" this is correct? Of course not! We don't even know that the next time we drop an apple, it will fall to the floor. Science is a process, though, and it isn't productive to dismiss the theories of today before we've seen the observations of tomorrow.

Re:Do we know? (1)

rlazarus (1002774) | more than 7 years ago | (#18256580)

It doesn't always work that way, though. A couple of thousand years before Neptune was discovered, there was a similar problem. At that point, science figured that all orbits were circular - it was simple, it was clean, but the problem was, it didn't quite fit the observations. So the answer was epicycles [wikipedia.org] : the planets still moved in circular orbits, but there were smaller loops tacked on, to make everything come out right.

It fit the data reasonably well, but let's face it - it was kind of silly. Okay, obviously it looks silly based on what we know now, but even objectively - epicycles are ridiculous. The solution, of course, was a much bigger change to the underlying model: what if orbits are elliptical, not circular?

Maybe dark matter is like Neptune, but maybe it's like the epicycles. Either it'll lead us to a momentous discovery, or we'll realize the flaw in the underlying theory - and later we'll look back and wonder what the hell we were thinking. We won't know until one of those two happens.

Re:Do we know? (2, Insightful)

Ibag (101144) | more than 7 years ago | (#18257822)

Well, I think that there is an important way in which this is nothing like epicycles. With the theory of epicycles, people (I hesitate to call them scientists) were looking to describe how the heavens moved without much thought of why. Here, scientists are working with a theory of why the world behaves as it does, and is trying to tweak parameters to make the model obey observation. When people added circles within circles to make the epicycles more accurate, there was no reasonable explanation for why this should be the case. Now, we have a reasonable sounding explanation that "the physics of over there should be the same as the physics over here." This is science. That was not.

Re:Do we know? (2, Interesting)

MightyMartian (840721) | more than 7 years ago | (#18256836)

I think the rate of expansion is an awfully good example. The standard inflationary model does have a problem in that it doesn't predict the expansion rate we see. Scientists have two choices when the data and the model don't jive. They can either toss the model and start from scratch, or attempt to alter the model to reflect observations. The decision to do either is one based upon how well other predictions of the model perform. In the case of the inflationary model, other aspects of the theory do explain other observations very well, so while we know there's a problem, we also know that it isn't a problem that completely devestates the existing theory. It means that the theory is not complete, and so, rather than tossing the theory, cosmologists and physicists will seek to refine the model, and that's what they're doing.

I suppose someone who doesn't understand the fundemental process might find dark matter and the like to seem ad hoc solutions, but when you consider that the main theory involved (General Relativity) does such an incredibly good job of modeling most of the other phenomona we see in the observable universe, it seems more reasonable to invoke something, possibly unseen, that could be playing a part, rather than tossing out an entire theory.

Re:Do we know? (0)

Anonymous Coward | more than 7 years ago | (#18255024)

Do discoveries like this mean anything at this time considering there's no way to prove any of it?

With FAITH you will find that PROOF is unimportant. Even though we can't PROVE that it is turtles all the way down, it is still IMPORTANT to sacrifice VIRGINS to appease them.

Same here (2, Insightful)

quokkapox (847798) | more than 7 years ago | (#18255252)

I've been semi-interested in Computer Science/Mathematics lately, and from everything I've seen and read so far, I've ascertained that we don't know much. Between dark fiber, optimal algorithms, P=NP, O(n log n) (and other equations like that), cryptography, etc. it seems like we just conveniently make up "stuff" to fit some model or equation. Do discoveries like this mean anything at this time considering there's no way to prove any of it?

[No offense intended--just pointing out that a lack of sophisticated understanding in a field of study does not imply the field is in any way bogus or the knowledge is "shaky". The reason it's called "dark matter" or "dark energy" is precisely because we aren't sure exactly what it is yet.]

Re:Same here (2, Funny)

$RANDOMLUSER (804576) | more than 7 years ago | (#18255394)

You might want to take a look at (I am NOT making this up) VB Helper Tutorial: Does P = NP? [vb-helper.com] ;D

Re:Same here (1)

Metasquares (555685) | more than 7 years ago | (#18256960)

I think it's funny that they used the VB operator for inequality: "P <> NP"

Re:Same here (1)

$RANDOMLUSER (804576) | more than 7 years ago | (#18257236)

I thought it was hysterical that they were explaining nondeterministic polynomial time to VB (I can't call them programmers) people.

Re:Do we know? (0)

Anonymous Coward | more than 7 years ago | (#18255260)

I would put it a different way: there's a lot that we don't know. There's also a lot that we do know, and a lot that we have a pretty good idea about. Just don't think of every result as a final result. Most of the time, people are working on intermediate, partial results, negative results, and other things that may not answer all of your questions right away. If all goes well, you eventually accumulate enough understanding that way to declare a particular problem "solved." This paper doesn't tell you how the galactic center makes TeV gamma rays. Instead, it tells you how 1-100 TeV protons convert themselves into high-energy gamma rays in a particular model of the galactic center. It's only one small puzzle piece. Call it a calculation, rather than a discovery.

At the same time, there are more detailed observations of the galactic center. They can rule out more and more models.

The process goes something like this: first you find something you don't understand. You write down all the models you can think of that might explain that thing, the wackier the better, as long as there's nothing to rule them out. At the same time, you make more and more observations, trying as hard as you can to prove each and every one of those models wrong. When the dust settles, you may find yourselves in one of three situations:

1. There are several (or lots of) models that fit the data. There's not enough information, and you have to admit you don't have any good way to decide which is right. That's the current state of dark matter and dark energy, but there's still a lot we can do to rule out more and more models.
2. There's one model left that fits the data. Hooray!
3. There are no models left that fit the data. What's really going on must be something you haven't thought of.

Re:Do we know? (1)

DiamondGeezer (872237) | more than 7 years ago | (#18255426)

By any chance, do you edit Wikipedia?

Re:Do we know? (3, Informative)

Fujisawa Sensei (207127) | more than 7 years ago | (#18256332)

We know a lot more than you give us credit for, perhaps you need to read a little deeper, try Relativity by Albert Einstein. AE just made up stuff because observations didn't fit Newtons proven model. So he just made up some equations to match the observations. But alas his made up equations didn't correctly model acceleration or gravity, so he made up GR.

GR is a very accurate theory, and there is experimental evidence of it. The two most famous are the perihelion precession of Mercury, and stars visible near the eclipsed sun. Of course being semi-interested in Cosmology/Astrophysics you would already know that.

Stuff like Dark Matter that just doesn't get made up, it falls out naturally when equations which are shown to work in one situation are shown to fail in another. DM vs GR for example. There's a lot of guess work as to what DM is, but that's where life gets interesting, we don't know what it is. We know 'something' is there, we just don't know what the something is. DM isn't a convenience item, its a wart, because without the wart GR which is shown to work in other cases could be used to correctly model galactic motion.

Re:Do we know? (4, Insightful)

ChrisA90278 (905188) | more than 7 years ago | (#18256524)

"Do discoveries like this mean anything at this time considering there's no way to prove any of it?"

There is no way in science to PROVE ANYTHING. All one can do is disprove a theory you can never prove a theory to be true. This is a very basic part of how science works

A theory is a good theory if it is predictive and makes good predictions and it is disprovable and it has not been disproved. But a theory can't be proven to be true.

Have you ever read Wittgenstein? Goggle the name. He wrote, long before the 1960's a question "Have I ever been to the moon?" He argued that while he thought he'd never been there and knew of no one who had he could not prove he's never been to the moon and further that such proof was impossible. Proof is very different from being very, very certain. He goes on to explain the difference and what can and can not be proven. Some things can never be proven not matter what you do

In science all you can be is "very certain" but must always be open to being proven wrong. For example we think and are very certain that light follows the inverse square law but can you prove that it ALWAYS does? It only takes one exception to disprove the theory but a trillion observations would not prove it true.

Re:Do we know? (0)

Anonymous Coward | more than 7 years ago | (#18258084)

Dude,

I fully empathize with you.

A few years ago i was wondering why galaxies are flat. To cut a longish story short, my questioning has lead me to this site (and others) http://www.holoscience.com/synopsis.php [holoscience.com]

Probably the most simple, obvious & 'close to home' challenge that demonstrates the lack of objectiveness in the current comsological climate is this - Ask yourself why nearly all the 'impact' craters on the moon are from 'impacts' that are perpendicular to the surface (from all sides! ie - where are the ones that 'skimmed' along the surface??). The site above gives you the answer. And it's not just the 'rogue' site above. Realise that there are scientists & engineers who are also saying that the current common understanding of the cosmos is up a black hole without a gamma ray paddle. And what's more - they have a coherent theory, a lot of which can be backed up by experiments in earth bound labs.

There's a lot more sites out there along the same lines as above, but what i'm convinced of is that we can demonstrate a lot more in the lab that is predictive of galaxies / plantary rings etc, without the need for the complex mathematics / relativity...and general 'darkness' that the current comsomological 'consensus' would have you believe.

Re:Do we know? (1)

larryduane100 (823439) | more than 7 years ago | (#18263956)

pygmy jesus-I am likewise able to see that mainstream astronomers make stuff up. Instead of revising theories, or beter yet, throwing discredited theories out, the bigbangers add layers of gobblygook to their gravity-only paradigm. The electric force is 10 to the 39th power stronger than gravity. Go to www.thunderbolts.info to learn all about a cosmology theory that makes sense AND backs it up with facts, experiments, predictions that actually come true, and much more! Larry

All I have to say is... (1, Redundant)

Kim Jong Ill (1033418) | more than 7 years ago | (#18254922)

Super massive black hole?! That SUCKS!!

Apparantly... (1, Funny)

spun (1352) | more than 7 years ago | (#18255748)

It sucks AND blows!

Re:Apparantly... (0)

Anonymous Coward | more than 7 years ago | (#18260330)

MEGA MAID. That's what I propose we change its name to.

Star near the black hole (0)

gr8_phk (621180) | more than 7 years ago | (#18255072)

Is this the object at the center of the galaxy? A while back someone posted a link to video of a star orbiting the center of our galaxy. It had a period of about 10 (11 or 12?) years and a closest approach to the black hole at a distance similar to the orbital radius of pluto. Since this star is observable and much closer to the black hole than 10 light years, it seem improbable that photons take a "random walk" out to a distance of 10 light years. That would make said star unobservable - wouldn't its light be spread all over the place? Or is the actual path not truely random, and the light is just delayed? Can someone explain the apparent discrepancy in this theory and the observed star?

Re:Star near the black hole (1)

Bandman (86149) | more than 7 years ago | (#18255192)

I would think that unless it rotated against the galactic plane, it would be rendered invisible half of the time it was on the far side of SgsA*

Re:Star near the black hole (0)

Anonymous Coward | more than 7 years ago | (#18255434)

I think it's the pRotons that take a random walk, not the pHotons. Once the protons produce the gammas, the gammas do indeed keep going at the speed of light.

It's an interesting question, though, how we can see the galactic center. We can see the stars near the galactic center in infrared, but not all wavelengths of light get through. There's a lot of dust in between that blocks visible light, so you have to go to either hard X-rays and gammas, or infrared.

Re:Star near the black hole (2, Informative)

btgreat (895041) | more than 7 years ago | (#18255490)

The article was talking about protons, not photons. I'm not exactly sure whether or not the motion is random, but it certainly shouldnt have any effect on whether the PHOTONS of the star are visible or not..

Re:Star near the black hole (2, Funny)

gr8_phk (621180) | more than 7 years ago | (#18257586)

Sorry. My dumb. I read too fast and saw all this stuff about gama radiation and my brain converted protons into photons. Hey, there you have it - proton decay due to dim gray matter - er uh dark matter.

Man the Battlestations! (2, Funny)

eno2001 (527078) | more than 7 years ago | (#18255110)

It's time to cue the Goatse jokes and links! Let's give 'em hell boys!

Errr... (0)

Anonymous Coward | more than 7 years ago | (#18255242)

I could've swore that Science Channel (US) already did a special on the Gamma Ray bursts that permeate our UNIVERSE . They concluded it was from distant, very distant galaxies that were elliptical, and rather young, but they had stated that the bursts were coming from SMBH's. While we do have a SMBH at the center of our galaxy, as do all galaxies, ours is currently not being 'fed'. Much of the mass nearby the SMBH has already been absorbed, or whatever the word would happen to be, by it leaving quite a large distance between it and any thing that could cause these Gamma ray bursts.

Incorrect summary (4, Interesting)

forand (530402) | more than 7 years ago | (#18255396)

The summary makes it sound as though this is an explanation for the DIFFUSE gamma-ray emission seen in our Galaxy. This is not the case, the paper only discuss a source of gamma-rays observed to be spatially coincident with the Galactic center. Gamma-ray telescopes do not have high angular resolution so there is a possibility that the gamma-rays are not actually coming from the Galactic center in the first place. Finally this is not a new proposal. Proton acceleration near black holes is quite commonly discussed and accepted. Furthermore photo-pion production is a well known process that has been well measured in the lab. I think the real meat of this paper is that they are suggesting observations of emission associated with the black hole that we have observed gravitationally for a while now. This is the big news, not that the gamma-rays in our galaxy have been explained, not that protons make pions which decay into gamma-rays.

the Science news article on the paper (0)

posterlogo (943853) | more than 7 years ago | (#18255450)

Pinball on a Galactic Scale By Phil Berardelli ScienceNOW Daily News 28 February 2007 The center of our Milky Way galaxy crackles with lethal gamma-rays, emitting trillions of electron volts of energy. Yet most astrophysicists consider our corner of the universe a relatively placid place, so the source of all this energy has remained mysterious. Now, members of an international team think they have found the answer: high-energy protons ejected by the supermassive black hole that lies at the heart of the galaxy. In 1998, scientists confirmed what they had long suspected: The Milky Way's center hosts an immense black hole, equivalent to the mass of about 2.6-million suns. Like all black holes, it pulls in huge amounts of matter to its ultimate doom. But when compared to the hearts of other galaxies, the Milky Way's hole had been considered puny, with not enough mass to generate much radiation in the gamma-ray wavelengths. Nevertheless, in 2004, astronomers found that the black hole was indeed generating gamma-rays, thereby forcing a search for the mechanism that could produce them. That mechanism appears to be magnetism. Reporting in this week's issue of Astrophysical Journal Letters, a team led by David Ballantyne of the University of Arizona in Tucson concludes that the Milky Way's central black hole is strong enough to generate a powerful but chaotic magnetic field that extends out a distance of about 10 light-years. To reach their conclusions, the researchers used computer programs to calculate the hypothetical trajectories of some 220,000 protons, which are ejected from the Milky Way's black hole and get bounced around by its magnetic field like in a galactic-sized version of a pinball machine. They then compared those paths with recent observations by ground-based instruments of the location of the gamma-rays and found that 69% of the computer-generated trajectories matched what the observed data were showing. The protons were slamming into hydrogen atoms within huge clouds of gas that slowly orbit the black hole about 10 light-years out. These collisions produce the gamma radiation astronomers have observed at the center of the Milky Way. Co-researcher Fulvio Melia, also of the University of Arizona, says the findings could help astrophysicists understand how the most powerful black holes in the universe likewise produce gamma radiation. "The same particle slinging almost certainly occurs in all black-hole systems," Melia says. The findings are interesting, but not necessarily conclusive, says astrophysicist Valerie Connaughton of NASA's Marshall Space Flight Center in Huntsville, Alabama. There could be an alternative explanation, such as a recent supernova in the vicinity of the galactic center, she says, which could be accelerating the high-energy protons being detected. Further observations are needed, she says, because "we still don't really understand all of the physics involved."

Now with formatting (1)

Anonymous Coward | more than 7 years ago | (#18255576)

Pinball on a Galactic Scale

By Phil Berardelli
ScienceNOW Daily News
28 February 2007

The center of our Milky Way galaxy crackles with lethal gamma-rays, emitting trillions of electron volts of energy. Yet most astrophysicists consider our corner of the universe a relatively placid place, so the source of all this energy has remained mysterious. Now, members of an international team think they have found the answer: high-energy protons ejected by the supermassive black hole that lies at the heart of the galaxy.

In 1998, scientists confirmed what they had long suspected: The Milky Way's center hosts an immense black hole, equivalent to the mass of about 2.6-million suns. Like all black holes, it pulls in huge amounts of matter to its ultimate doom. But when compared to the hearts of other galaxies, the Milky Way's hole had been considered puny, with not enough mass to generate much radiation in the gamma-ray wavelengths. Nevertheless, in 2004, astronomers found that the black hole was indeed generating gamma-rays, thereby forcing a search for the mechanism that could produce them.

That mechanism appears to be magnetism. Reporting in this week's issue of Astrophysical Journal Letters, a team led by David Ballantyne of the University of Arizona in Tucson concludes that the Milky Way's central black hole is strong enough to generate a powerful but chaotic magnetic field that extends out a distance of about 10 light-years. To reach their conclusions, the researchers used computer programs to calculate the hypothetical trajectories of some 220,000 protons, which are ejected from the Milky Way's black hole and get bounced around by its magnetic field like in a galactic-sized version of a pinball machine. They then compared those paths with recent observations by ground-based instruments of the location of the gamma-rays and found that 69% of the computer-generated trajectories matched what the observed data were showing. The protons were slamming into hydrogen atoms within huge clouds of gas that slowly orbit the black hole about 10 light-years out. These collisions produce the gamma radiation astronomers have observed at the center of the Milky Way.

Co-researcher Fulvio Melia, also of the University of Arizona, says the findings could help astrophysicists understand how the most powerful black holes in the universe likewise produce gamma radiation. "The same particle slinging almost certainly occurs in all black-hole systems," Melia says.

The findings are interesting, but not necessarily conclusive, says astrophysicist Valerie Connaughton of NASA's Marshall Space Flight Center in Huntsville, Alabama. There could be an alternative explanation, such as a recent supernova in the vicinity of the galactic center, she says, which could be accelerating the high-energy protons being detected. Further observations are needed, she says, because "we still don't really understand all of the physics involved."

the xeelee (0)

Anonymous Coward | more than 7 years ago | (#18255958)

are coming...

old (1)

mrtexe (1032978) | more than 7 years ago | (#18256192)

Over twenty years ago, physicist Paul LaViolette [etheric.com] stated that gamma rays emanate from the center of the galaxy. (See prediction 12 at the link)

No, the black hole does not "got my tongue." (1)

Impy the Impiuos Imp (442658) | more than 7 years ago | (#18256798)

the protons, flung outward with energies up to 100 TeV by the intense magnetic fields near the event horizon, as they make a random walk through the plasma environment. It can take thousands of years for them to travel 10 light-years from the black hole, where they collide with lower-energy protons to form pions. These decay into gamma radiation emanating from a torus-shaped region around the central object.


Or so it appears, according to the subatomic particles God set in motion "already on their way", when creating the universe 6000 years ago.

Dumbass scientists. >:(

so black holes dont suck and destroy? (1)

sabrex15 (746201) | more than 7 years ago | (#18257100)

so what im gathering is that black holes take in everything (time/space/light..etc) but emit gamma rays??????

Re:so black holes dont suck and destroy? (1, Informative)

Anonymous Coward | more than 7 years ago | (#18257546)

No, they still don't emit anything (except Hawking radiation, and that's kind of complicated). These gamma rays are from protons getting close to the event horizon, but then getting shot away at incredibly high energies due to interactions with the massive magnetic fields in the area. They then smack into other particles, releasing a shower of sub-particles and gamme rays.

Re:so black holes dont suck and destroy? (1)

sabrex15 (746201) | more than 7 years ago | (#18264094)

thanks for shedding some light on that for me.

Paging Teela Brown (0, Redundant)

savage1r (856578) | more than 7 years ago | (#18258406)

Prepare to receive my Hot Needle of Inquiry. (I put it in a reply to a lower post but it's too good a line to leave hidden :P)

Bah, Gravity!!! (0, Troll)

Khyber (864651) | more than 7 years ago | (#18259666)

In Soviet Korea.....

http://ftw.generation.no/img/sovietkorea.jpg [generation.no]

Parent is Goatse troll (1)

kalirion (728907) | more than 7 years ago | (#18261804)

Mod parent down, the link is to Goatse.

Re:Parent is Goatse troll (1)

Khyber (864651) | more than 7 years ago | (#18265878)

Screw you, generations got majorly hotlinked last night. It's supposed to be a bunch of Korean soldiers all in the middle of a high-jumping exercise. All I did was give a link to the image.

Not my fault some other asshole decides to hotlink the damned image and ruin this post for everyone else.

And *THIS* is why Slashdot needs the ability to edit posts, so we can kinda catch ourselves if things like this happen and correct it before it gets too overly-fucked.

So, for those who modded me down, yea, you're right to do so, it's just too bad you couldn't look at the image and realize it was taken down because someone hotlinked it, which is expressly written on the image, and maybe cut me some fucking slack since I didn't do the hotlinking.

Adjust it? (1)

KoldKompress (1034414) | more than 7 years ago | (#18260158)

I can see how this would work. If my desktop gets too dark and I can't see things properly, I adjust the gamma.
Even I winced at that one.
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