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Astronomers Find Brightest Pulsar Ever Observed
An anonymous reader writes: Astronomers using the Chandra X-ray Observatory and the NuSTAR satellite have discovered a pulsar so bright that it challenges how scientists think pulsars work. While observing galaxy M82 in hopes of spotting supernovae, the researchers found an unexpected source of X-rays very close to the galaxy's core. It was near another source, thought to be a black hole. But the new one was pulsing, which black holes don't do. The trouble is that according to known pulsar models, it's about 100 times brighter than the calculated limits to its luminosity (abstract). Researchers used a different method to figure out its mass, and the gap shrank, but it's still too bright to fit their theories.
Maybe its just me but who else but astronomers would find any pulsar, much less the latest to attain the title of "brightest". How do they administer the IQ tests?
With a blackhole behind it? I don't know shit about how X-ray works but i think it passes through a star, right?
Moderating "-1, Disagree" is simple censorship. Have the guts to post your opinion. -- Spazmania (174582)
Maybe they have stumbled upon some new type of star or object. There are probably all kinds of large things that we have never run across before.
Liar! It's Xenu!
Discredited? The evidence simply isn't strong enough for that.
The obvious reason for such a beam is some alien kid playing with his xray toy pointer.
That, or possibly theoretical models that put 95% of stuff into not yet observed dark matter/dark energy are still a bit immature.
---- MISSING MISCELLANEOUS DATA SEGMENT --- [sigdash] trolololol
We better start the invasion early.
"Look at that star! It's so bright, like it's pointed straight at us! That can't be ri--"
"If a nation expects to be ignorant and free in a state of civilization, it expects what never was and never will be."
It's aliens!!!
This is one of the areas I think the electric universe guys are correct about.
http://www.thunderbolts.info/t...
I love Jesus, except for his foreign policy.
It's because of God, our creator. ...
Nah, I'm just fucking with you.
Literally, who (around here) cares? See the evidence and do a comment count on most astronomy (and other natural sciences) articles. Most barely hit 30 comments before they get archived, save for the odd "We need to fund NASA more/less" article. Why do the editors post these stories anyway? Mandatory "we also do space" article?
My thought about what a pulsar is... Think about the way the moon causes the liquid part of the earth to stretch in the directions both exactly toward the moon and exactly away from it. Now imagine a binary star system, but one star has gained enough mass to become a black hole. However, you've got that other star circling around the black hole - stretching it into an oval shape. If the black hole isn't huge (just above the critical mass required to be a black hole), then perhaps the distortion of the gravity field is sufficient such that it allows the light to escape at the side facing the other star, and the opposite side. Since the side facing the star would be obscured by the star itself, we'd only see the other side - a focused beam of light that would otherwise be trapped inside a black hole. Very exciting for me.
This is one of the areas I think the electric universe guys are correct about.
http://www.thunderbolts.info/t...
No they're not. Stop going to those websites. Everything on there is nonsense. Pulsars are a fairly well understood fenomena. Astronomers have found 1 observation out of billions of stars that contradicts their math, and they already have a plausible explanation for it.
That kind of runs counter to how general relativity works though. Once something is passed an event horizon, there is no distorting or moving the event horizon to make something peak out again. So you couldn't really get a spot of a black hole that allows light to escape, much less a moving one. Even stuff falling would be difficult to behave that way, because there is a region around the black hole without stable orbits, so stuff falls in fast. But beyond that, where stable orbits exist, material gets stuck in the accretion disk until friction and other effects allow its momentum to be transfered away so it can fall in. You end up with a large pile up of stuff up until a point, then a trickle of sparse stuff. At least in some cases, the spinning rate of the pulsar can be on the order of hundreds of times a second, and that limits how large the spinning area can be.
We have observed binary systems with a black hole or other compact object in it before though. They've been important for GR, because the decay rate of their orbits has matched predictions of energy loss from the emission of gravity waves.
I believe the point is that they made the math to match the observations. If their assumptions are incorrect, then the math they made up will be based on those false assumptions, like current cannot exist in space. Which does not make sense to me since we obviously have the northern lights being created by current flow from the sun. And now we know about the magnetic tubes that form every 15 minutes that connect from the sun to the earth. Perhaps the assumptions made decades ago need to be revisited.
Now I will admit that some of the extents they go to on that site go too far and seem too much of a stretch. Everything gets put into being evidence of the electric universe even when there are simpler explanations. But the basic idea of current flow at massive scales may have some merit.
-- ssoorrrryy,, dduupplleexx sswwiittcchh oonn.. -Quote found on actual fortune cookie.
I don't find their hypothesis very persuasive. They don't go into any details. How exactly is this mechanism supposed to work? How high luminosities should be expected? What limits on pulse rates does their model predict? How is the energy generated? How large are pulsars? If they aren't compact objects, why do we have pairs of them that are separated by half the diameter of the sun?
If the standard model of pulsars were held to the same stnadard of handwaviness, one wouldn't even have discovered that there might be a problem with a too high luminosity for this pulsar. You only discover that sort of problems once you actually get down to it and calculate the consequences of your model. Examples of predictions made by the neutron star model of pulsars is: Pulsars should have quite well-defined maximum and minimum masses, and maximum and minimum sizes and surface gravities. They can't be too light, or they wouldn't collapse to form neutron stars, they would be white dwarves instead. And they can't be too heavy, or they would collapse to form black holes. These upper and lower bounds are called the Chandrasekhar limit (1.4 solar masses) and Tolman–Oppenheimer–Volkoff limit (about 3 solar masses). If the neutron star is to stay together it can't rotate so fast that the centrifugal force wins over gravity. This, together with the limits on surface gravity and diameter implies a maximum rotation frequency. All pulsars we have seen so far fit with these limits.
The reason why a too high luminosity is considered problematic is that the energy source of ultraluminous pulsars is belived to be accretion: Matter falling down towards the surface of the neutron star, and converting lots of potential energy into kinetic energy and then heat radiation as it does so. But if too much radiation is emitted, this radiation exerts a pressure on the infalling matter that is so great that it pushes the matter back out. So if the pulsar (or any other thing driven by accretion) gets too bright, it ends up starving itself, and can't stay brighter than the point where radiation exactly cancels gravity for very long. That limit is called the Eddington limit, and the problem in this case is that the pulsar is 100 times brighter than this limit.
You can get around the Eddington limit by allowing for an asymmetric infall: More matter falling from some directions than other directions (example: a meteor hitting the earth is asymmetric accretion). But it's hard to go all the way up to 100 times the Eddington limit with realistic accretion scenarios. So this really is an interesting object.
But my point is that the Electric Universe guys don't do anything to explain the power source of the pulsar. If one assumes that it is powered by accretion as in the standard model, then they have exactly the same problem as the standard model. And if it isn't powered by accretion, where does it get its energy from? The article you link to talks about emission mechanisms, but not where the energy comes from in the first place. Also, the link they give to the press release is about a variant on the standard neutron star picture - it does not support the Electric Pulsar hypothesis.
I can't even find any references of "Red Shift" being discredited except by fringe crazies. I have found articles talking about a certain amount of uncertainty that may need to be adjusted based on our findings of space expansion, but nothing that says it's "wrong".
When an object collapses to a black hole, its gravity doesn't get any stronger. If you replaced the Sun with a black hole of the same mass, the Earth would continue in the same orbit, and light would behave quite normally in the solar system. The only place where strange stuff happens is when you get very close to the black hole (a few km away from its center in the case of one with the mass of the sun).
Still, let's assume that a star has somehow ended up really close to a black hole. First of all, if the star is so close that it experiences the kind of extreme gravitational lensing you describe, if would be so close that the black hole would be inside the star. Black hole radii are typically a few kilometers, and the heavily distorted regions are a few times that. Star radii are millions of kilometers.
But let's assume that the star is really compact, so you can have it close enough to the black hole to be interesting without actually touching it. In that case, you can get one of the beams you want, but not both of them. The easy one to get it the one that goes from the start, past the black hole and then towards us. That one gets stronger when the star is at moderate distances. The beaming in the other direction requires the star to be super-close to the black hole - so close that it couldn't be in a stable orbit.
So the best version of this model would have a tiny, bright star in an orbit around a black hole, being periodically magnified by the lensing of the black hole as it passes behind it (seen from us). It wouldn't really look like a pulsar, though.
love. it. one hundred times brighter seems pretty bright but i bet i could hold the pulsar directly up to my eye and still be pretty much somewhat possibly okay for the most part. perhaps.
It is what it is.
Sounds like a perfect question for an XKCD What-If....
Think about the way the moon causes the liquid part of the earth to stretch in the directions both exactly toward the moon and exactly away from it.
Nothing's stretching away. In order of distance from the Moon we have:
1) nearside oceans
2) the Earth itself
3) farside oceans
All of them are attracted towards the Moon, but at decreasing strength due to distance. The nearside ocean gets pulled closer to the Moon than the Earth does, and the Earth gets pulled closer to the Moon than the farside ocean does. Hence, two bulges, but not because the far one is being pushed away from the Moon.
However, you've got that other star circling around the black hole - stretching it into an oval shape.
When you say "it," do you mean the star or the black hole? It seems like you mean the black hole...
A black hole isn't a physical object. It's a surface around an object at which the gravitational field strength has a particular value. I'm not sure it would be influenced in such a way by the presence of another object.
then perhaps the distortion of the gravity field is sufficient such that it allows the light to escape
What light are you talking about?
systemd is Roko's Basilisk.
I believe the point is that they made the math to match the observations. If their assumptions are incorrect, then the math they made up will be based on those false assumptions
Nope, you're thinking of axiomatic systems not science.
In science when you find observations that contradict your predictions you scrutinize the model to see if you can find mistakes or refine it to make better predictions.
It's a system specifically designed to make the best of limited knowledge and to find ways of fixing mistakes stemming from incorrect assumptions.
I expect it's instrument error. This is becoming a regular thing: (1) Make measurement, (2) form hypothesis, (3) send to marketing department, (4) great new discovery reported in the media, (5) discover error in calculation/instrument calibration/methodology, (6) secure tenure, (7) retract previously hyped assertion, (8) go to (1).
FFS Basic plasma phsyics courses cover all of that shit those guys say.
Luckily for many of us,the basics of plasma physics used in space and astrophysics are very very well understood. Most science problems arise from complexity (turbulence, kinetic scales etc) and we mostly try to get better data and better simulations.
Saying the foundations of plasma physics are shaky is like saying for atmospheric sciences that hydrodynamics is wrong because we still can't predict the weather more than 5 days ahead.
For the specific thing you mention current can exist in space because space is not empty. Its a plasma, there are charged particles and they create currents when they move around in funny ways. The flow from the sun is quasi neutral in general and although northen lights are indeed caused by charged particles its their high energies that causes the funny colors and not the fact that there is current in general.
In the same way there are pretty straightforward responses to everything those guys are saying its just that people that spent enough time of their lives studying this field generally have better things to do
You do understand that x-rays are light, right?
...around 12 millions years ago
Why wouldn't it be influenced? Think about a binary star system. Replace one of the stars with a black hole and nothing is really different. I'm not sure how you could say that it wouldn't be influenced by the presence of another object...
The light - well the light that would otherwise be emitted if the star weren't of sufficient mass to have it's event horizon be outside of it's physical outer boundary. The "it" that I referred to in "stretching it into an oval shape" is really the event horizon of the black hole.
I'm one of those that doesn't believe in the singularity aspect of a black hole. I think a black hole is just a star that has sufficient mass and density such that it's event horizon is beyond it's exterior. I don't think anything magical happens inside, I think it's just a regular star, or a neutron star. Even there were a singularity, my idea about pulsars isn't really any different.
The idea is simply that, the gravity field of a single star, black hole, or planet if it has no neighbors is spherical. If it's in a tight orbit with another body, as is with a binary star system, then it's gravitational field could be considered elliptical (if you imagine removing the other body - like take the moon out of the picture and just think about the earth's gravity field - it would be eliptical). I'm making the jump that the event horizon of a black hole in a binary system would also be elliptical. If that gravity field IS elliptical, then it's possible that radiation (I called it light) could escape at the edges.
Arp's discordant redshifts were dead in 1975 when it was realized a uniform distribution of galaxies in a volume created the 1/z distribution of angular separation. Arp and supporters always ignored this. Details described in Discordant Redshifts: A Post-Mortem. Support among professionals has been rapidly dying off, in every sense of the expression, leaving mostly nothing but 'fanboys'.
One of Electric Universe claims greatest problem is where the power comes from to drive the claimed currents (see Challenges for Electric Universe 'Theorists'...).
In theory, you're right. But my idea is that the event horizon (which is related directly on the gravity of the body within) is NOT necessarily spherical, but instead is elliptical due to the gravity of the second body. As you say you've witnessed this, I would imagine that in a lot of cases, the black hole is sufficiently massive - or the binary twin is not massive enough - to warp the event horizon to the point that light could escape. I'm talking about special cases, where the opposite is true... Either the black hole is not so far away from not being a black hole (I mean, in terms of mass), and/or the orbiting body is massive enough to have the effect of warping that event horizon to the point that it's below the body's surface. (or the gravity is weak enough to allow light to escape - you could think about this in terms of the event horizon or the gravity of the body. Keep thinking about it... I swear it makes sense when you get the right frame of mind.
I believe the point is that they made the math to match the observations.
Maths that accurately describes the physical world is DISCOVERED not "made up". Seriously, read a fucking text book and immunise yourself against that populist nonsense.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
Do not look at pulsar with remaining good eye.
But my idea is that the event horizon (which is related directly on the gravity of the body within) is NOT necessarily spherical, but instead is elliptical due to the gravity of the second body. As you say you've witnessed this, I would imagine that in a lot of cases, the black hole is sufficiently massive - or the binary twin is not massive enough - to warp the event horizon to the point that light could escape.
This just flat out does not work in general relativity. If you want to toss out GR, fine, but then you would have very little basis to make any statement about black holes then. Otherwise there is the issue in GR that event horizons can only expand, and not shrink or re-expose things that have crossed it. Adding more mass to a system can stretch it out, but cannot let it go back or move the part that is stretched out in a sense.
and/or the orbiting body is massive enough to have the effect of warping that event horizon to the point that it's below the body's surface.
There is no body surface just below the event horizon in GR. From a far away perspective, the surface fades from view as it is red shifted approaching the event horizon, moving the event horizon doesn't change this (not that it can move in such a way). From the perspective of someone who fell into the black hole, the star has collapsed to a point. Once something has crossed the event horizon, from its perspective it would take an infinite force to stop it from falling further in.
And how many examples of that happening in physics and astronomy do you have? Especially considering it takes a lot more than a single PR piece to get tenure these days, and while competing projects are looking for the chance to publish errors or check observations (especially in astronomy).
I hope so, because you do NOT want to smell a turtle-fart. And if it's turtles all the way down, that's a lot of fart.
Sleep your way to a whiter smile...date a dentist!
The idea is simply that, the gravity field of a single star, black hole, or planet if it has no neighbors is spherical. If it's in a tight orbit with another body, as is with a binary star system, then it's gravitational field could be considered elliptical
I'm not clear on why this should be the case. Can you really push and pull gravity around like it's a physical object?
systemd is Roko's Basilisk.
That is some of the most asinine shit I have heard. You seem to not understand the difference between "made to match" and "made up". Try learning to read what people write sometime.
From your statement then the Copernican heliocentric math would have been discovered and so it must accurately describe the physical universe. Jeeze, what a dumb-ass!
-- ssoorrrryy,, dduupplleexx sswwiittcchh oonn.. -Quote found on actual fortune cookie.
Sort of... If two massive bodies were orbiting each other, if you were standing on one of them - if you were directly underneath the other body, you would be lighter. If you were directly perpendicular to the other body, you would be heavier.
My hunch is that opposing gravitational forces don't add up in that way when you're talking about forces so strong that light is too slow to escape them, or that for another object to influence the gravity of the black hole that much, it would itself have to be either so close as to be within the event horizon, or so dense as to have an event horizon of its own which overlaps the first.
systemd is Roko's Basilisk.
All math is made up. Math would not exist if humans (or some other sentient life form) did not. It is no more than another language, created by humans for precise communication.
The star is powered externally by currents in the cosmic plasma.
I love Jesus, except for his foreign policy.