Six nearby unique galaxies makes no particular sense. Thus the
conclusion here is suspect also. The actual apparent mass may also
be a relativistic effect which can certainly ramp up observed mass.
So we have an interesting anomaly and the first explanation makes me
uncomfortable. Once one assumes relativistic effects, we can
postulate plausible scenarios that may even include several adjacent
galaxies. It may represent a natural transition phase of all
galaxies and we have just picked up the correct locale to observe it.
In the meantime the theorists are sent back to school to figure it
out.
Monster Black Hole
Is Biggest Ever Found
by Elizabeth Howell,
SPACE.com Contributor
Date: 28 November 2012
Astronomers have
discovered what may be the most massive black hole ever known in a
small galaxy about 250 million light-years from Earth, scientists
say.
The supermassive
black hole has a mass equivalent to 17 billion suns and is
located inside the galaxy NGC 1277 in the constellation Perseus. It
makes 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 really
oddball galaxy," said study team member Karl Gebhardt of the
University of Texas at Austin in a statement. "It's almost
all black hole. This could be the first object in a new class of
galaxy-black hole systems."
The giant black hole
is about 11 times as wide as the orbit of Neptune around our sun,
researchers said. The mass is so far above normal that the scientists
took a year to double-check and submit their research paper for
publication, according to the study's lead author, Remco van den
Bosch.
"The first time I
calculated it, I thought I must have done something wrong. We tried
it again with the same instrument, then a different instrument,"
van den Bosch, an astronomer at Germany's Max Planck Institute for
Astronomy, told SPACE.com. "Then I thought, 'Maybe something
else is happening.'"
Galactic evolution
questioned
The finding may have
implications for our understanding of how giant black
holesevolve in the center of galaxies.
Astronomers typically
believe that the size of the central part of a galaxy, and the black
hole inside of it, are linked. But the vastly different proportions
seen in NGC 1277 are calling that into question.
NGC 1277's black hole
could be many times more massive than its largest known competitor,
which is estimated but not confirmed to be between 6 billion and 37
billion solar masses in size.It makes up about 59 percent of its host
galaxy's central mass - the bulge of stars at the core. The object's
closest competitor is in the galaxy NGC 4486B, whose black hole takes
up 11 percent of that galaxy's central bulge mass.
However, van den
Bosch's team says it has also spotted five other galaxies
near NGC 1277 that look about the same, and may also harbor gigantic
black holes inside of them.
"You
always expect to find one sort [of a phenomenon], but now we have six
of them," van den Bosch said. "We didn't expect them,
because we do expect the black holes and the galaxies to influence
each other."
The research is
detailed in tomorrow's (Nov. 29) edition of the journal Nature.
Black hole census
Van den Bosch said his
team discovered the mega black holes during a survey to seek "the
biggest black holes we could find."
The astronomers
analyzed the light coming from 700 galaxies, using an immense
light-gathering telescope: the Hobby-Eberly Telescope at the
University of Texas at Austin's Mcdonald Observatory.
From that large
survey, they found six galaxies with stars and other objects whipping
about inside of them at unusually high average speeds — more than
218 miles a second (350 kilometers). The galaxies also were small, at
less than 9,784 light-years across.
Suspecting the speed
and size measurements meant massive black holes lay inside these
galaxies, the team used Hubble Space Telescope archival
data of NGC 1277 and discovered the large black hole.
The team also noted
that NGC 1277 has only old stars inside it. The youngest stars in the
galaxy are 8 billion years old, almost twice the age of our sun.
Van den Bosch said he
is curious to know if these large black holes only formed in the
early years of the universe.
"It could just be
this thing has been sitting around since the Big Bang and not done
much since then," he said. "It might be a relic of what
star formation and galactic formation looked like at that time."
The MacDonald
Observatory's StarDate night sky publication has an encyclopedia of
black holes here:http://blackholes.stardate.org
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