Six nearby unique galaxies makes no particular sense. Thus theconclusion here is suspect also. The actual apparent mass may alsobe a relativistic effect which can certainly ramp up observed mass.
So we have an interesting anomaly and the first explanation makes meuncomfortable. Once one assumes relativistic effects, we canpostulate plausible scenarios that may even include several adjacentgalaxies. It may represent a natural transition phase of allgalaxies and we have just picked up the correct locale to observe it.
In the meantime the theorists are sent back to school to figure itout.
Monster Black HoleIs Biggest Ever Found
by Elizabeth Howell,SPACE.com Contributor
Date: 28 November 2012
http://www.space.com/18668-biggest-black-hole-discovery.html
Astronomers havediscovered what may be the most massive black hole ever known in asmall galaxy about 250 million light-years from Earth, scientistssay.
The supermassiveblack hole has a mass equivalent to 17 billion suns and islocated inside the galaxy NGC 1277 in the constellation Perseus. Itmakes up about 14 percent of its host galaxy's mass,compared with the 0.1 percent a normal black hole would represent,scientists said.
"This is a reallyoddball galaxy," said study team member Karl Gebhardt of theUniversity of Texas at Austin in a statement. "It's almostall black hole. This could be the first object in a new class ofgalaxy-black hole systems."
The giant black holeis about 11 times as wide as the orbit of Neptune around our sun,researchers said. The mass is so far above normal that the scientiststook a year to double-check and submit their research paper forpublication, according to the study's lead author, Remco van denBosch.
"The first time Icalculated it, I thought I must have done something wrong. We triedit again with the same instrument, then a different instrument,"van den Bosch, an astronomer at Germany's Max Planck Institute forAstronomy, told SPACE.com. "Then I thought, 'Maybe somethingelse is happening.'"
Galactic evolutionquestioned
The finding may haveimplications for our understanding of how giant blackholesevolve in the center of galaxies.
Astronomers typicallybelieve that the size of the central part of a galaxy, and the blackhole inside of it, are linked. But the vastly different proportionsseen in NGC 1277 are calling that into question.
NGC 1277's black holecould be many times more massive than its largest known competitor,which is estimated but not confirmed to be between 6 billion and 37billion solar masses in size.It makes up about 59 percent of its hostgalaxy's central mass - the bulge of stars at the core. The object'sclosest competitor is in the galaxy NGC 4486B, whose black hole takesup 11 percent of that galaxy's central bulge mass.
However, van denBosch's team says it has also spotted five other galaxiesnear NGC 1277 that look about the same, and may also harbor giganticblack holes inside of them.
"Youalways expect to find one sort [of a phenomenon], but now we have sixof them," van den Bosch said. "We didn't expect them,because we do expect the black holes and the galaxies to influenceeach other."
The research isdetailed in tomorrow's (Nov. 29) edition of the journal Nature.
Black hole census
Van den Bosch said histeam discovered the mega black holes during a survey to seek "thebiggest black holes we could find."
The astronomersanalyzed the light coming from 700 galaxies, using an immenselight-gathering telescope: the Hobby-Eberly Telescope at theUniversity of Texas at Austin's Mcdonald Observatory.
From that largesurvey, they found six galaxies with stars and other objects whippingabout inside of them at unusually high average speeds — more than218 miles a second (350 kilometers). The galaxies also were small, atless than 9,784 light-years across.
Suspecting the speedand size measurements meant massive black holes lay inside thesegalaxies, the team used Hubble Space Telescope archivaldata of NGC 1277 and discovered the large black hole.
The team also notedthat NGC 1277 has only old stars inside it. The youngest stars in thegalaxy are 8 billion years old, almost twice the age of our sun.
Van den Bosch said heis curious to know if these large black holes only formed in theearly years of the universe.
"It could just bethis thing has been sitting around since the Big Bang and not donemuch since then," he said. "It might be a relic of whatstar formation and galactic formation looked like at that time."
The MacDonaldObservatory's StarDate night sky publication has an encyclopedia ofblack holes here:http://blackholes.stardate.org
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