Here we go again with the hypothetical Black Hole. At least we do know that a star succumbed. My problem right now is the apparent speed of the interaction and the apparent emission. It takes years for light to cross a Galaxy. It should still take years for a star to reach an event horizon after initial observation.
What is true is that this complex of events provides us a measurement test that my surprise us. I hope someone picks up of that. I am getting tired at images that really look lit up and truly huge when they could well be close by. We still really do not know just what we are looking at except a stack of quite reasonable guesses.
A measurement test here could change all that..
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Astronomers watch black hole burp after eating a star
"The destruction of a star by a black hole is beautifully complicated, and far from understood," Sjoert van Velzen says. (Credit: NASA Goddard Space Flight Center/Flickr)
Posted by Arthur Hirsch-Johns Hopkins on
http://www.futurity.org/black-hole-eats-star-1058062-2/?utm_source=feedly&utm_medium=webfeeds
Scientists have for the first time witnessed a black hole
swallow a star and then quickly eject a flare of stellar debris moving
at nearly light speed.
Astrophysicists tracked the star—about the size of our sun—as it
shifted from its customary path, slipped into the gravitational pull of a
supermassive black hole, and was sucked in, says Sjoert van Velzen, a
Hubble fellow at Johns Hopkins University.
“These events are extremely rare,” says van Velzen, lead author of the study published in the journal Science.
“It’s the first time we see everything from the stellar destruction
followed by the launch of a conical outflow, also called a jet, and we
watched it unfold over several months.”
Black holes are areas of space so dense that irresistible
gravitational force stops the escape of matter, gas, and even light,
rendering them invisible and creating the effect of a void in the fabric
of space.
Astrophysicists had predicted that when a black hole is force-fed a
large amount of gas, in this case destroying a whole star, then a
fast-moving jet of wreckage in the form of plasma—elementary particles
in a magnetic field—can escape from near the black hole rim, or “event
horizon.” This study suggests this prediction was correct, the
scientists say.
“Previous efforts to find evidence for these jets, including my own,
were late to the game,” adds van Velzen, who led the analysis and
coordinated the efforts of 13 other scientists in the United States, the
Netherlands, Great Britain, and Australia.
Supermassive black holes, the largest of black holes, are believed to
exist at the center of most massive galaxies. This particular one lies
at the lighter end of the supermassive black hole spectrum, at only
about a million times the mass of our sun, but still packing the force
to gobble a star.
It all started with a tweet
The first observation of the star on its path to destruction was made
by a team at the Ohio State University, using an optical telescope in
Hawaii. That team announced its discovery on Twitter in early December
2014.
After reading about the event, van Velzen contacted an astrophysics
team led by Rob Fender at the University of Oxford in Great Britain.
That group used radio telescopes to follow up as fast as possible. They
were just in time to catch the action.
By the time it was done, the international team had data from
satellites and ground-based telescopes that gathered X-ray, radio and
optical signals, providing a “multi-wavelength” portrait of this event.
It helped that the galaxy in question is closer to Earth than those
studied previously in hopes of tracking a jet emerging after the
destruction of a star. This galaxy is about 300 million light years
away, while the others were at least three times farther away. One light
year is 5.88 trillion miles.
The first step for the international team was to rule out the
possibility that the light was from a pre-existing expansive swirling
mass called an “accretion disk” that forms when a black hole is sucking
in matter from space. That helped to confirm that the sudden increase of
light from the galaxy was due to a newly trapped star.
“The destruction of a star by a black hole is beautifully
complicated, and far from understood,” van Velzen says. “From our
observations, we learn the streams of stellar debris can organize and
make a jet rather quickly, which is valuable input for constructing a
complete theory of these events.”
Support for this study came from multiple sources, including NASA,
the Netherlands Foundation for Scientific Research (NOW), the European
Research Council, the International Centre for Radio Astronomy Research,
the Alfred P. Sloan Foundation, and the Australian Research Council.
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