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Black Hole Found Inside Globular Cluster
acidrain writes "Contrary to the prediction of some computer models, scientists have found a black hole resting peacefully in a dense nest of stars called a globular cluster. Previously discovered black holes are either similar in size to a large star, or super massive holes which are millions of times bigger than a star is able to remain stable. This finding indicates there may be an intermediate size range of holes residing within these star clusters."
How many black hole discoveries do we need to announce before they no longer become news? Are the previous announcements falling into the gravity well of a collapsed star or something?
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I didn't think black holes rest easily when material crosses the event horizon to be shredded violently into atomic pieces. If there was a black hole in the neighborhood, I don't think anyone would rest easily.
This finding indicates there may be an intermediate size range of holes
Much like the modern workplace.
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The singularity is a point but the Schwarzchild radius around it is directly proportional to mass. One earth mass is equivalent to something like a few cm of Schwarzchild radius.
Inside the Schwarzchild radius everything falls into the hole regardless of velocity, no exceptions.
The important question is, does this black hole have a warning label?
WARNING: do not drop spaceship keys into black hole
So when an atronomer gets fired or doesn't get a raise, he says, "Man! I got it up the black hole!"
Or, if there's someone on the research team that's a real jerk, do they call him a "blackhole"?
If you lived on a planet of the star closest to the black hole, would the passing of your time be measurably different from ours?
I don't know the meaning of the word 'don't' - J
"People have seen stellar-sized black holes that form from [an exploded] star, and then there are the super-massive black holes at the centres of galaxies that are millions of times the mass of our Sun - but there's nothing in between.
That's what we've seen because that's where we've gone looking. You'd expect holes to form from supernovas, so you look at the center of planetary nebulae, where stars used to live before they exploded. You'd expect them to form at galactic centers, so you look there to find them. There's nothing in between because we haven't gone looking for the in-betweens yet.
Sometimes I read stuff like this and look at pictures of space it really emotionally affects me. Millions of stars and billions of planets
:)
inside clusters of galaxies containing trillions more stars. I get that goose bumpy feeling. Sometimes it just makes me cry.
Then I think about the sweaty palmed lawyers in their grey little suits, the strutting politicians and power hungry cowards whos lives
are not even a grain of sand in the ocean of time. And I laugh. It makes me really belly laugh to think of our pathetic little monkey
species scrapping over a few drops of oil on a tiny rock. It's like seeing every self appointed pompus prick who ever had the audacity
to call themselves a "judge" or "leader" of anything stipped naked of their clothes and humiliated by the sheer majesty of it all.
Yeah rocks! It's almost enough to make you religious isn't it.
As far as I remmember, black hole have the same mass as the collapsing star (before starting slowly to dissipate). Thus the same gravity as the as the star would be felt at the same distance. There is albeit a difference, within the schwarschild radius, the gravity pull is enough to pull everything without possible escape even light. Normally this radius smaller than the radius of the star itself before collapsing, if the mass would be at a point. In other word if the sun was to suddenly transform in black hole, the earth would happily go wander on the same orbit.
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Urectum!
So THAT'S where I left that thing, I'd been looking all over for it!
You see? You see? Your stupid minds! Stupid! Stupid!
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Millionth Monkey's excellent reply got a 5: Informative, as it should.
But on the top level of Slashdot, it shows as a 3!
I can think of reasons this might be so, but if they are right, you are missing something by it.
There is no clue besides a sense of smell that a very valuable answer was here.
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if it's in a cluster of stars that's really old, it's probably had time to suck up several and normally I don't think we'd be able to tell if say it ate five stars and got 5x bigger (well the event horizon goes out further, it doesn't actually get bigger) but if I remember correctly, gravity increases exponentially when mass is added, which is why the moon at 1/3 the size has 1/6 the gravity as earth so if it sucked up 5 stars, it would look like a couple hundred times larger and be quite noticeable.
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"Globular clusters, which are found in the halo of a galaxy, contain considerably more stars and are much older than the less dense galactic, or open clusters, which are found in the disk." - http://en.wikipedia.org/wiki/Globular_cluster What this makes me wonder is how the Globular Cluster, being much older than other galactic structures neither spins, nor contracts into itself. I would think that a Black Hole at the center would gobble the stars closest to it, increasing its gravitational attraction so that all of the surrounding stars would free fall straight "down" into it. The spin of other galaxies makes it so that stars do not just fall straight down into their own central black holes, but instead fall in a spiral toward it so that it takes a very long time for them to fall into it. But the Globular Cluster, with stars just hanging there in a spherical shape around it... I must ask - how come the stars have not fallen into the center long, long ago? Anyone have a theory on that?
If you don't look for something in a particular place, you won't find it there. This is so obvious that Heisenberg called it his Duh! Principle (little-known fact). The corollary of this principle is you won't know if something is in a particular place until you look for it there. This led Heisenberg to develop his Uncertainty Principle, and social studies has never been the same since.
The stars in a globular cluster don't just 'hang there in a spherical shape'. They're all in orbit around the common center of mass. Just like the planets in the solar system are in orbit around their common center of mass - except that the orbits of stars in a globular cluster have all different inclinations (ie, they don't orbit in a common plane), eccentricities (ie, some are on practically circular orbits while others are on almost radial orbits), and energies (ie, some move further out in the cluster than others). Think about it - even if there weren't a black hole in the cluster, the stars can't just be stationary. Their common gravitational attraction would indeed have caused them to collapse together long ago. It's only their large velocities (typically ~10 km/s) which support the cluster.
The cool thing about globular clusters, which happens almost nowhere else in the universe, is that the stars are close enough together that strong interactions are fairly common (on an astronomy scale this means a timescale of maybe tens or hundreds of millions of years). This means that the stellar orbits are altered relatively frequently. The cumulative effects of weak (distant) interactions also modify the orbits constantly. Occasionally you'll even get a direct stellar collision, although this is rare. Most of the stars in a globular cluster never pass close enough to any central black hole to have their orbits altered by the hole. Only stars which pass very near to the hole will feel its strong gravitational influence. This causes a cusp of stars to accumulate in the centre of the cluster, detectable both in terms of stellar density and stellar velocities. This is one means of inferring the presence of a central hole - looking at the velocities of the central cluster stars. With present technology, this is only really possible for nearby clusters (basically those belonging to the Milky Way). In the case from the article the cluster is more distant and the detection has been done from X-ray emission (from stuff falling into the hole).
I just read "Schwarzchild anus" :(
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> According to Electric Universe theory, which explains the cosmos much better than nuclear physics, relativity, and quantum physics
That's wishful thinking. Everyone knows that Time Cube Theory is the correct one.
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The following article has a little more info than the original (and a dodgy artist's impression of a stellar-mass black hole):
Black hole boldly goes where no black hole has gone before
Inside the Schwarzchild radius everything falls into the hole regardless of velocity, no exceptions.
And we know this how?
for that link. It led me eventually to a wonderful web site.
That site, in turn, got me to Are You a Quack?.
Years ago, my being a Physics major qualified me as a crank magnet. I guess the Physics professors were too busy so I was dealing with the overflow.
"We can't solve problems by using the same kind of thinking we used when we created them." -- Albert Einstein
http://en.wikipedia.org/wiki/Special_relativity
And we know this how? While it would probably be better to say "no known exceptions", we do have a fairly good set of data on this. The evidence is pretty strong, from what's been observed, that radiation, light, matter, and the entire electromagnetic spectrum is unable to escape, regardless of velocity. Keep in mind that a Black Hole, by definition, cannot be escaped by anything. This is according to the theories which initially predicted and defined black holes, based upon general relativity. Indeed, if anything escapes from within the Schwarzschild Radius, the object in question is not, by definition, a black hole.
IANAQP, of course, but it appears debatable whether Hawking Radiation escapes or not. I've read little on the subject, but it seems that Hawking Radiation, if it indeed exists and the theories are correct, originates from just beyond the event horizon anyways.
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