Scientists Find Wind Blowing From Our Milky Way's Black Hole (space.com) 22
After 50 years of searching, astronomers say they have finally found evidence of a long-sought "wind" blowing from Sagittarius A*, the supermassive black hole at the center of the Milky Way. "Unless a black hole exists in a perfect vacuum, it must blow a wind somehow. And there is no perfect vacuum in the universe," team co-leader and Northwestern University researcher Mark Gorski said in a statement. "With new observations, this is the first time we've had a clean enough view to see the wind's imprint. We looked at the data and said, 'There it is. There is the thing that everybody's been looking for for 50 years.'" Space.com reports: Scientists have been aware for some time that feeding black holes launch powerful outflows of material around them, including jets and winds. Winds are caused when matter falling to the black hole is accelerated to near light-speed, generating pressure that pushes infalling material away. That has been seen with ravenously feeding black holes before, but not the barely feeding Sgr A*. Its sparse consumption of material and the fact it is obscured by the plane of the Milky Way from our vantage point have made tracing this wind difficult.
Gorski's Northwestern colleague and team co-leader Lena Murchikova pointed out that the scientists were the first to detect molecular gas very close to Sgr A* feeding the supermassive black hole. That makes Sgr A* reassuringly like other supermassive black holes. "The wind is not powerful, and its direction probably wanders with time. It shows that our black hole is not unique, and our place in the universe is not unique," Murchikova added. "To observe our own black hole, we have to look through the plane of our galaxy. That means we have to peer through gas, dust and ionized structures, and you can't really see through all of that easily."
While the team's results confirm that Sgr A* is extremely quiet compared to the supermassive black holes that sit in bright, turbulent regions of other galaxies called active galactic nuclei (AGN), this black hole wind is no slouch. In fact, the scientists think that it has been raging for around 20,000 years. "The majority of other galaxies spend most of their lives in a state where they are not particularly active," Murchikova said. "But we can only see them when they are in a fireworks stage. It is very attractive to study black holes when they are in the fireworks stage, but that's not actually their dominant state. "Sgr A* finally gives us a window into the life of a black hole in this quiet state." The team's research was published in The Astrophysical Journal Letters.
Gorski's Northwestern colleague and team co-leader Lena Murchikova pointed out that the scientists were the first to detect molecular gas very close to Sgr A* feeding the supermassive black hole. That makes Sgr A* reassuringly like other supermassive black holes. "The wind is not powerful, and its direction probably wanders with time. It shows that our black hole is not unique, and our place in the universe is not unique," Murchikova added. "To observe our own black hole, we have to look through the plane of our galaxy. That means we have to peer through gas, dust and ionized structures, and you can't really see through all of that easily."
While the team's results confirm that Sgr A* is extremely quiet compared to the supermassive black holes that sit in bright, turbulent regions of other galaxies called active galactic nuclei (AGN), this black hole wind is no slouch. In fact, the scientists think that it has been raging for around 20,000 years. "The majority of other galaxies spend most of their lives in a state where they are not particularly active," Murchikova said. "But we can only see them when they are in a fireworks stage. It is very attractive to study black holes when they are in the fireworks stage, but that's not actually their dominant state. "Sgr A* finally gives us a window into the life of a black hole in this quiet state." The team's research was published in The Astrophysical Journal Letters.
huh (Score:3, Funny)
Is, is that a fart joke?
Re: huh (Score:4, Funny)
Re: (Score:2)
Re: (Score:2)
it is farting in our general direction.
Re: (Score:2)
Timothy, you did not let me down.
A Mighty Wind? (Score:2)
As it were
Naughtiest slashdot caption ever (Score:5, Funny)
At least until something happens to uranus.
Re: (Score:2)
Something violent happened to Uranus. Why do you think it's tipped over on its side?
Re: (Score:2)
nope, was never straight
So there's ... (Score:2)
So a Black Hole can violate physics laws... (Score:2)
...it really is the only thing that can suck and blow at the same time.
I don't get it (Score:1)
"Winds are caused when matter falling to the black hole is accelerated to near light-speed, generating pressure that pushes infalling material away."
It's always been my understanding that black holes pull everything into them and nothing can escape.
So if this wind is escaping, then that was wrong?
Re:I don't get it (Score:5, Informative)
Stuff falling in is really falling quite a long way. If its path doesn't intersect the event horizon, ie, it "misses" the black hole: it either smacks (really hard) into other stuff down there that's also not quite fallen in, or slingshots back out. The event horizon being comparatively small, a lot of stuff ends up either in a very hot accretion disk around the black hole, or being blown back out in jets or winds.
This is why black holes are the hearts of some of the most energetic astrophysical objects in the universe: powered by stuff almost falling in, and all that gravitational potential energy turning to kinetic energy turning to thermal energy.
Re: I don't get it (Score:2)
Too much Beavis and Butt-Head (Score:1)
I initially read that as:
Scientists Find Wind Blowing From Our Milky Way's Bung Hole
What does the black hole wind smell like ? (Score:2)
No, this is not a fart reference as space does have a smell [nasa.gov].
However: the thought of fart smell made me write this comment.
Sagittarius A* (Score:2)
Show me your A*