New class of black holes discovered
July 1, 2009
This is an artist's impression of the new source HLX-1 (represented by the light blue object to the top left of the galactic bulge) in the periphery of the edge-on spiral galaxy ESO 243-49. This is the first strong evidence for the existence of intermediate mass black holes. Credit: Heidi Sagerud.
A new class of black hole, more than 500 times the mass of the Sun, has been discovered by an international team of astronomers.
The finding in a distant galaxy approximately 290 million light years from Earth is reported today in the journal Nature.
Until now, identified black holes have been either super-massive (several million to several billion times the mass of the Sun) in the centre of galaxies, or about the size of a typical star (between three and 20 Solar masses).
The new discovery is the first solid evidence of a new class of medium-sized black holes. The team, led by astrophysicists at the Centre d'Etude Spatiale des Rayonnements in France, detected the new black hole with the European Space Agency's XMM-Newton X-ray space telescope.
"While it is widely accepted that stellar mass black holes are created during the death throes of massive stars, it is still unknown how super-massive black holes are formed," says the lead author of the paper, Dr Sean Farrell, now based at the Department of Physics and Astronomy at the University of Leicester.
He added: "One theory is that super-massive black holes may be formed by the merger of a number of intermediate mass black holes. To ratify such a theory, however, you must first prove the existence of intermediate black holes.
"This is the best detection to date of such long sought after intermediate mass black holes. Such a detection is essential. While it is already known that stellar mass black holes are the remnants of massive stars, the formation mechanisms of supermassive black holes are still unknown."
"The identification of HLX-1 is therefore an important step towards a better understanding of the formation of the super-massive black holes that exist at the centre of the Milky Way and other galaxies."
A black hole is a remnant of a collapsed star with such a powerful gravitational field that it absorbs all the light that passes near it and reflects nothing.
It had been long believed by astrophysicists that there might be a third, intermediate class of black holes, with masses between a hundred and several hundred thousand times that of the Sun. However, such black holes had not been reliably detected until now.
This new source, dubbed HLX-1 (Hyper-Luminous X-ray source 1), lies towards the edge of the galaxy ESO 243-49. It is ultra-luminous in X-rays, with a maximum X-ray brightness of approximately 260 million times that of the Sun.
The X-ray signature of HLX-1 and the lack of a counterpart in optical images confirm that it is neither a foreground star nor a background galaxy, and its position indicates that it is not the central engine of the host galaxy.
Using XMM-Newton observations carried out on the 23rd November 2004 and the 28th November 2008, the team showed that HLX-1 displayed a variation in its X-ray signature. This indicated that it must be a single object and not a group of many fainter sources. The huge radiance observed can only be explained if HLX-1 contains a black hole more than 500 times the mass of the Sun. No other physical explanation can account for the data.
Source: University of Leicester (news : web)
Sep 17, 2008 |
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Still, it is interesting to have a *fourth* (not a third) size class of blackholes. This fills in the gap between stellar and the sub-supermassive intermediate blackholes.
This article must have been written by someone in Leicester's art department:P.
How is it that they always have "artists conceptions" instead of the actual enhanced x-ray photograph from the observatory?
I'm tired of always seeing "artists renditions" of observations. It sucks.
Not true. If currently accepted theories are true, you can't see the black hole itself, but you should certainly be able to see a large number of X-rays emitted by hawking radiation and other processes. You should also be able to observe any remaining accretion disks directly through the radition they would produce.
Yes, you should see everything electromagnetic which is coming from the accretion disk near the black hole as incredibly red shifted, and the closer you get to the black hole, the greater the shift should be.
Thus ultraviolet light is shifted towards the visible spectrum, and visible light is shifted towards the infrared.
For events occuring very, very near the event horizon, red shifts could occur of several orders of magnitude in the frequencies of the electromagnetic radiation. This 500 sols black hole would have an event horizon about 10,017 km in radius. So radiation coming from within about a few hundred thousand kilometers should be incredibly red shifted. This effect is caused directly by the black hole's gravity, and is not related to the direction of motion of the radiation's specific source within the acretion disk.
This means that all radiation comming from a black hole was produced at a much, much higher frequency than it appears to have been produced at.
I share the concerns of Quantum_Conundrum.
There are probably two reasons for so many "artists conceptions" but no actual enhanced photographs of Black Hole observations:
1. There are no Black Holes. Repulsive interactions between neutrons, first reported here ["Attraction and repulsion of nucleons: Sources of stellar energy", Journal of Fusion Energy 19 (2001) 93-98], prevent their formation.
2. Actual photographs of a "Black Hole" would be appear to be photographs of a neutrons star -- which it probably is.
With kind regards,
Oliver K. Manuel
http://www.omatumr.com
1) Look for an accretion disk (x-rays are a good indicator)
2) Look for a companion object orbiting around something unseen
3) Detect gravitational waves, if the black hole is in a tight orbit around another object (especially if that other object is another black hole).
From Squiggly Lines to Spatial Images
Thanks,
Oliver K. Manuel
http://www.omatumr.com
Thanks, earls.
Do obvious similarities between published drawings of Neutron Stars and Black Holes reflect only the limited creativity of the artists?
Or is this a subliminal way that creative artists expose truths that conflict with the limited views of scientists?
The truth is this: Nuclear mass data, when displayed in the Cradle of the Nuclides, show strongly repulsive interactions between neutrons that prevent the collapse of Neutron Stars to Black Holes: http://tinyurl.com/lvxs95
With kind regards,
Oliver K. Manuel
http://www.omatumr.com
Nothing says "classy" like clogging comments sections of unrelated articles with your own papers and faulty logic. Seriously? An artist draws something that you say "looks like a neutron star" (which, uh, haven't been "imaged" either, depending on whatever the hell you mean by that word), therefore that's evidence for your far out theory. Congrats!
If your science is legitimate, it will be filtered, examined, and accepted through the normal channels. There's no need to spam articles and use false evidence to support your cause.
Ha.!
Check the citations to this paper in Google scholar.
They are all (12) self referenced.
In seven years nobody used his work but himself.
I think the scientific method failed for O.K. Manuel and he now tries new venues.