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Gabriel Perez Diaz, Instituto de Astrofisica de Canarias (Servicio MultiMedia)
This image is a simulation of the X-ray binary system Swift J1357.2-0933, a black hole and star system, in which the effect of a strange, vertical mystery structure are at their maximum.
By Nola Taylor Redd, SPACE.com
Astronomers studying an unusual black hole system have spotted a never-before-seen structure in the disk of matter encircling the system.
Swift J1357.2, an X-ray binary system that regularly emits outbursts of high energy, consists of a black hole slowly consuming its companion star. Matter from the doomed star falls into the accretion disk, which surrounds the black hole, feeding it dust and gas.
While observing the system, a team of scientists noticed an unusual vertical feature traveling through the material.
"It's the first time we can resolve such [a] structure in an accretion disk, and it might be ubiquitous in X-ray binaries during the outburst state," Jesus Corral-Santana, of the Astrophysical Institute of the Canary Islands in Spain, told SPACE.com by email. [The Strangest Black Holes in the Universe]
A hidden structure
The black hole contained in Swift J1357.2 is one of the millions of stellar black holes that dot the Milky Way galaxy.
About three times as massive as the sun, the behemoth likely formed when a single star collapsed inward on itself. The resulting, city-sized body packed a great deal of mass into a tiny package, creating a strong gravitational pull on nearby dust and gas.
Located in the Virgo constellation, approximately 4,900 light-years from Earth, Swift J1357.2 also contains a small companion star, which has only a quarter the mass of the sun. This companion star orbits the pair's center of mass every 2.8 hours, one of the shortest known orbital periods for such systems.
The black hole pulls material from the companion star into its accretion disk, occasionally emitting the X-ray bursts that enabled scientists to find this otherwise hard-to-spot system, researchers said.
Corral-Santana and his team took hundreds of optical images of the system using the Isaac Newton and the William Herschel Telescopes, both of which are in the Canary Islands. Studying the light produced by the accretion disk, the researchers noticed a periodic dimming in the system, sometimes occurring over the course of only a few seconds.
"Since the orbital period of the system is 2.8 hours, those dips cannot be produced by eclipses of the companion star. They are much faster," Corral-Santana said. "Therefore, they must be produced by a hidden structure placed very close to the black hole, in the inner accretion disk."
The new find can only been seen in the outer, optical portion of the accretion disk, not on the inside, where X-ray bursts originate. The X-ray emission, which shows no periodic variation, unlike its optical counterpart, indicated a vertical structure was hiding the black hole, Corral-Santana said.
Rather than appearing at a set, predictable time, the structure shows up over a steadily increasing period, indicating a wave-like movement through the accretion disk.
"It is a wave produced in the accretion disk, moving outward," Corral-Santana said, "like the wave produced when a stone is dropped in calm water."
The missing population
The wave-like feature also provides information about the orientation of the black hole.
Objects in space face Earth at a variety of angles, or inclinations. They can be seen edge-on, face-on or somewhere in between. Swift J1357.2 is the only one of 50 suspected similar black-hole systems found with an edge-on accretion disk — what scientists call a high inclination. However, astronomers think approximately 20 percent of these systems should provide such a perspective.
In order to see the wave-like structure in the accretion disk, scientists must have such an edge-on view of the disk, or one close to it. A view from a lower inclination, closer to face-on, would not reveal the sudden rises and falls in the total light coming from the system.
"Swift J1357.2 is the prototype of the hitherto missing population of high-inclination black holes in transient X-ray binaries," Corral-Santana said.
Because Swift J1357.2 is the first such system to allow such an edge-on view, the presence of the vertical structure takes on an added significance. No signs of such structures appear in other similar systems, but that could result simply from their unfortunate angles. Such structures could in fact exist in other, previously discovered transient X-ray binary systems, hidden only by their observational angles.
The findings were published online Feb. 28 in the journal Science.
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Leave a Comment:
It is a rare thing to find an article that has NO comments on it. Guess there's nothing to say about this "discovery", except this : "FIRST!" and possibly, "ONLY!":-D
Need a stellar mass black hole who's accretion disk is edge on, in a binary system? The universe provides.
"The resulting, city-sized body"------ this is all just theory, no one has seen a black hole yet, we have made many inferences, B U T, it is still theory. Good theory, perhaps. In any event, I think it might be a good idea to think of Saturn rings and ringlets when thinking about accretion disks, We have observed that system and surely we could make some inferences from there. For my part, no matter the size of the actual black hole, I can't imagine that event horizon is only tens of miles or so in diameter, not given the resolution of our scopes from 5kLY, So that wave must be moving fast!! I wonder if it is Relativisticly fast, or just fast. (all theory of course). I wonder if there is anyway we could assign a black hole a quantum number, and check it periodically to see if it changes (like a giant entangled qbit)....hey, it's friday, someone call it in to ira's science fridays.....
>ray smith "The resulting, city-sized body"------ this is all just theory, no one has seen a black hole yet
Well, it's all math. For example, on the surface of the Earth, we know that gravity accelerates things downwards at about 9.8 Meters/second^2, and we can therefore calculate that an escape velocity is about 40,000 kilometers (~25,000 miles) per hour.
If the Earth was the same mass it is now, but if it was bigger and less dense - let's say the Earth was 30,000 KM in diameter rather than 12,700 KM. Then we'd be farther from the center of this mass, and the escape velocity would be down to about 25,000 KM (~15,500 miles) per hr.
Likewise, if the Earth was still the same mass, but was smaller and more dense, so that we were closer to the center of this mass, the escape velocity would be higher, and we'd need to go faster and faster to be able to escape in a rocket.
We can calculate if a man standing on Pluto or Vesta or Io or Titan could fire a .308 and see if the bullet traveling 2,500 feet per second would or wouldn't have enough speed to escape - it's all math. (Yes, I know the man would die on Pluto, and Yes, I took my Hunter Safety course and I know it's bad to randomly fire a rifle pointed upwards....) It's all well known math, and given a planet or a star of any given mass, you can calculate how physically small, and how dense it would have to be in order to have an escape velocity of any certain speed.
So, if you take a body that is... let's say 3 solar masses like this article... then you can calculate what the escape velocity would be at a Jupiter equivalent orbit, and at Earth's orbit and so on. You can calculate that inward and the escape velocity will keep going up and up and up as we make the star smaller and more dense and as we get closer to the center of that mass. And when that caclulated escape velocity get's to 1c (~300,000,000 KM/HR) there's your 'event horizon'.
Doing the math on their star with 3 Solar Masses, the event horizon is about 17.7 KM (~11 miles).
huh? anybody wanna another beer?
The wording of the article leads to some gross misconceptions. The comment that the collapse creates a gravitational pull on nearby objects is very misleading. Objects located outside the original star experience the same gravitational pull, assuming no mass is lost in the collapse. Since the gravitational pull is classically proportional to the inverse square of the distance from the center of the star. So objects inside the original radius of the star would experience a high gravitational pull. The collapse of the star does not create greater gravitational pull assuming the same mass.
The net gravitational pull on an object decreases as you travel inside of a star or planet until it reaches zero at the center. This is because as you travel inward the mass above you pulls in the opposite direction and cancels some of the inward pull. The collapse of the star now creates a very small star so that objects inside the original radius of the star do not experience a cancellation of forces. The collapse of the star does not create a stronger gravitational field, but allows objects which are extremely near to experience a stronger gravitational field.
This type of article needs to be proofed by a good physicist who is sensative to the linguistics. There are too many articles which make mistakes like this. Incidentally since when a star explodes only part of it ends up in a black hole, so the gravitational pull outside of its original radius actually decreases substantially, so the comment is factually wrong for planets orbiting the star before and after it exploded.
Per statement - "Swift J1357.2, an X-ray binary system that regularly emits outbursts of high energy, consists of a black hole slowly consuming its companion star. Matter from the doomed star falls into the accretion disk, which surrounds the black hole, feeding it dust and gas."
Another less inappropriate use of an anthropomorphic analogy, but still; i.e. black holes do not "consume" stars and the expectation that matter pulled in is "feeding" black holes is uproven. Such misleading imagry presents and inaccurate perspective of cosmological interactions such as one consideration that black holes can grow or shrink. While there are a lot of references to a theoretical conjecture for a Black Hole "packing on the pounds," I can find no real empirical evidence online relevant to observable growth/shrinkage measurments data such as increased density relative to a black hole's static size or increased size relative to a black hole's static density.
Additionally the latest consensus is that there is not a relevant relationship between the observable size of the accumulated bulge about the Black Hole and the size of the Black Hole itself. Similarly large black holes have been observed in small galaxies and small black holes have been observed in large galaxies.
scientist were surprised? than they are scientists in name only.
it is not very scientific to have expectations of the way "something should be"
You mean like climate change. That branch of "science" is full or expectations and hoped for conclusions.
think our congress in washington , d.c. is stuck in a black hole . there like going no where .
anybody heard any black hole jokes...
Naaahh, plain bob... the dumb blond jokes are still way too popular.
Let me know if you need any, and I'll send you lot's of them(blond jokes).
At least no one is saying God created this, just like he created quarks and in only 6000 years...LOL The universe is infinite and dwarfs the masses and media both, conceptually. Astro-physicists can be spoofed in a hit comedy show but never interviewed on "The View" or David Letterman nor show up on the History Channel, when theology is open for debate?!
OK, but where are you getting that the universe is infinite? Last I heard, scientiss believed that it was a closed, finite system - possibly one of an infinite (or not) number of possibilities, but not in itself infinite.
It is infinite, because our brain cannot comprehend its size, except to use symbols, thus infinity. Can you conceive of billions of galaxies? You can conceptualize it and say it with words but you can't create a picture of it in your mind and our senses are not capable of measuring our environment in that way. Scientists know the relative age of the universe but cannot see beyond the limits of infrared, time lapse representations from our best telescopes and computer technology. What's beyond that? Dark matter is a theory but we haven't seen it our found it. I think you are referring to "string theory or M theory, which postulates multiple universes, based on mathematical formulas. It is not something which anyone has proved.
did you hear bout the guy at NASA...He got a pair of pair of black socks for christmas...just discovered a new 'black hole' in them...
I love lamp
Enough of this important science stuff. Tell me more about the Kardashians and Justin Bieber!
'Important' is a relative term. It is definitely important to the poor companion star being slowly consumed by the black hole, but generally speaking, what happens to the Kardashians and Justin Bieber probably has a greater impact on most peoples lives here on planet earth.
Sad, but true.
If you believe that what happens to celebrities during their 15 minutes is more important to the human race than discovering the fundamentals of universal mechanics and furthering the scientific knowledge of our species, then you have some serious lack of critical thinking skills my friend.
I'll bet the intensity levels of the black hole's X-ray levels must be off the charts or near immeasurable!
There's just no way any sort of computerized probe can get close enough for even it's signals to analyze and/or send enough pertinent data back to earth or wherever from. Unless it's tried from the "side" of the black hole.
Just one of the most fantastic wonders and sights of the universe...!!
I remember watching the SyFy Channel's show, "StarGate SG-1". They had a fantastic and entertaining episode on the theories of a another galaxy's black hole-- with it's pulling effects coming thru the Stargate-- and threatening planet Earth! They showed how the black hole's pull would affect "time dilation" and sucking all matter, light, and sound into itself.
Catch that particular episode of "StarGate SG-1"-- if you find the re-runs!