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Baby Black Hole With Big Appetite
kuni ito writes: "'According to the astronomers who detected the object with Japan's Advanced Satellite for Cosmology and Astrophysics (ASCA), the black hole seems to be acting like a supermassive black hole, despite its size. It's sucking up matter at roughly the same rate as its much larger (and seemingly less hungry) relatives, they said.'" This black hole (assuming that black holes exist) seems to be eating a lot more than would otherwise be predicted.
What I find interesting is how they say its a "small" black hole thats gobbling up "lots of stuff". Yet the only way we have of detecting black holes is through the amount of x-ray radiation that escapes at the poles, and heating of dust as it rotates and falls inward.
A black hole that has contradictory data about its size would obviously point to the existence of a seperate unidentified object.
Black Holes and Beyond
Black Holes: Mystery of the Cosmos
Black Hole: The Death of a Star
Shit Load of Links
Any similarity to a real person is purely coincidental
Bill Gates would be a suitable name for it.
Fh
-leoglas
i've looked at love from both sides now. from win and lose, and still somehow...
Many low luminosity galaxies, although showing evidence of having very massive black holes at their center, appear less bright than expected given the calculated size of their black holes. This has been explained by models which assume that the black holes in question are "underfed", i.e. that there's no longer enough matter close enough to the holes to create larger amounts of radiation.
However, the galaxy described in this paper, NGC4395, is an exception to this scenario, which is why it is interesting. Although it is of similar low luminosity to the galaxies described above, according to this paper, it shows evidence of containing a much smaller black hole than other low-luminosity galaxies. This smaller hole is from 10,000 to 100,000 solar masses, which is small for a galactic-core black hole.
The paper concludes that NGC4395 behaves more like a brighter galaxy with a larger hole, but because its hole is small, it appears dimmer. Attempting to apply the massive-underfed-hole model to this galaxy, based on it having low luminosity, gives incorrect results; instead, the model that applies is that of brighter galaxies with larger holes, except that in this case, the hole is smaller and thus the galaxy dimmer.
The space.com article actually did manage to say something along these lines, but you have to completely ignore the first half of the article, which is confused nonsense, and read the following paragraphs:
Until now, scientists had speculated that black holes residing in galaxies with dim cores - such as NGC 4395 - were either too old or too small to quickly eat up lots of material, as more massive black holes do on a regular basis. But now it seems that "mid-mass" black holes (a new nickname for the smallest type of supermassive black holes) may simply be more efficient matter-eaters.
"We now see that the nuclear source in NGC 4395 is a scaled-down version of black holes found in the most luminous of galaxies," said, Andrew Fabian, another Institute of Astronomy researcher who worked on the discovery. "Everything is the same, only it is smaller."
As a result, some astronomers now think that the total output of X-rays from accreting matter may therefore be more a product of how massive the black hole is, rather than of the luminosity of the region surrounding the black hole, as it once was thought.