Thu Nov 29, 2012, 12:26 AM
joshcryer (58,523 posts)
“Oddball” Galaxy Contains the Biggest Black Hole Yet (Horizon 4 light days across!)
"Oddball" Galaxy Contains the Biggest Black Hole Yet
It’s thought that at the heart of most if not every spiral galaxy (as well as some dwarf galaxies) there’s a supermassive black hole, by definition containing enormous amounts of mass — hundreds of millions, even billions of times the mass of our Sun packed into an area that would fit inside the orbits of the planets. Even our own galaxy has a central SMBH — called Sgr A*, it has the equivalent of 4.1 million solar masses.
Now, astronomers using the Hobby-Eberly Telescope at The University of Texas at Austin’s McDonald Observatory have identified what appears to be the most massive SMBH ever found, a 17 billion solar mass behemoth residing at the heart of galaxy NGC 1277.
Located 220 million light-years away in the constellation Perseus, NGC 1277 is a lenticular galaxy only a tenth the size of the Milky Way. But somehow it contains the most massive black hole ever discovered, comprising a staggering 14% of the galaxy’s entire mass.
“This is a really oddball galaxy,” said Karl Gebhardt of The University of Texas at Austin, a team member on the research. “It’s almost all black hole. This could be the first object in a new class of galaxy-black hole systems.”
Karl Gebhardt also made a video which explains it in more detail (how they discovered it, etc). I was amazed that they could track star orbits of another galaxy so well. I know that's how the Milky Way's supermassive black hole was discovered.
4 replies, 2602 views
“Oddball” Galaxy Contains the Biggest Black Hole Yet (Horizon 4 light days across!) (Original post)
Response to longship (Reply #1)
Thu Nov 29, 2012, 03:02 AM
bananas (27,486 posts)
3. There could be advanced civilizations trapped inside
It's big enough that you could survive entering it,
and there might even be advanced civilizations inside.
April 11, 2011
Planets Could Orbit Singularities Inside Black Holes
The discovery of stable orbits inside certain kinds of black hole implies that planets and perhaps even life could survive inside these weird objects, says one cosmologist
It’s well known that a traveller passing through a black hole’s event horizon arrives in a region in which the radial dimension becomes time-like, rather than space-like. Conventional orbits are clearly impossible here.
But travel further in and there is another horizon where the dimensions switch back again (at least, inside charged and rotating black holes). This is the inner Cauchy horizon and it’s beyond here that Dokuchaev says the interesting orbits for massive planets exist.
That raises an interesting question: whether a planet in such an orbit could support a complex chemistry that is rich enough to allow life to evolve.
Dokuchaev clearly thinks so. “Advanced civilizations may live safely inside the supermassive BHs in the galactic nuclei without being visible from the outside,” he says, somewhat speculatively.
Response to bananas (Reply #3)
Thu Nov 29, 2012, 06:56 AM
joshcryer (58,523 posts)
4. That's mind numbingly insane.
Though for their presence to be known there would have to be evidence of white holes, which there exist none (though black holes fit the description as being both black and white in the equations according to Hawking radiation; in which case such civilizations could never be known or proven).
Still. Wow. Interesting and fascinating concept. I would think such civilizations would realize their utter demise though. I mean, they are guaranteeing themselves a heat death. In a galaxy such as Hall's Galaxy I suppose it may be a preferable outcome.
Response to joshcryer (Original post)
Thu Nov 29, 2012, 02:51 AM
Confusious (8,317 posts)
2. I was going to say I don't believe it
But I misread "comprising a staggering 14% of the galaxy’s entire mass" as "comprising a staggering 14% of the universe's entire mass."
14% of the galaxy's mass is reasonable after that.