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Submission + - Another large Black hole in "our" Galaxy (arxiv.org)

RockDoctor writes: A recent paper on ArXiv reports a novel idea about the central regions of "our" galaxy.

Remember the hoopla a few years ago about radio-astronomical observations producing an "image" of our central black hole — or rather, an image of the accretion disc around the black hole — long designated by astronomers as "Sagittarius A*" (or SGR-A*)? If you remember the image published then, one thing should be striking — it's not very symmetrical. If you think about viewing a spinning object, then you'd expect to see something with a "mirror" symmetry plane where we would see the rotation axis (if someone had marked it). If anything, that published image has three bright spots on a fainter ring. And the spots are not even approximately the same brightness.

This paper suggests that the image we see is the result of the light (radio waves) from SGR-A* being "lensed" by another black hole, near (but not quite on) the line of sight between SGR-A* and us. By various modelling approaches, they then refine this idea to a "best-fit" of a black hole with mass around 1000 times the Sun, orbiting between the distance of the closest-observed star to SGR-A* ("S2" — most imaginative name, ever!), and around 10 times that distance. That's far enough to make a strong interaction with "S2" unlikely within the lifetime of S2 before it's accretion onto SGR-A*.)

The region around SGR-A* is crowded. Within 25 parsecs (~80 light years, the distance to Regulus [in the constellation Leo] or Merak [in the Great Bear]) there is around 4 times more mass in several millions of "normal" stars than in the SGR-A* black hole. Finding a large (not "super massive") black hole in such a concentration of matter shouldn't surprise anyone.

This proposed black hole is larger than anything which has been detected by gravitational waves (yet) ; but not immensely larger — only a factor of 15 or so. (The authors also anticipate the "what about these big black holes spiralling together?" question : quote "and the amplitude of gravitational waves generated by the binary black holes is negligible.")

Being so close to SGR-A*, the proposed black hole is likely to be moving rapidly across our line of sight. At the distance of "S2" it's orbital period would be around 26 years (but the "new" black hole is probably further out than than that). Which might be an explanation for some of the variability and "flickering" reported for SGR-A* ever since it's discovery.

As always, more observations are needed. Which, for SGR-A* are frequently being taken, so improving (or ruling out) this explanation should happen fairly quickly. But it's a very interesting, and fun, idea.

Submission + - Surado, formerly Slashdot Japan, is closing at the end of the month. (srad.jp) 1

AmiMoJo writes: Slashdot Japan was launched on May 28, 2001. On 2025/03/31, it will finally close. Since starting the site separated from the main Slashdot one, and eventually rebranded as "Surado", which was it's Japanese nickname.

Last year the site stopped posting new stories, and was subsequently unable to find a buyer. In a final story announcing the end, many users expressed their sadness and gratitude for all the years of service.

Comment Re:Perfect (Score 1) 54

It doesn't look like they have. I just spent 3 minutes trying to hear some of the music from this band, or at least learn what kind of music it is. Literally the only thing I can find for free is an M&Ms commercial they made. Asking people to pay money to listen to a band they've never heard before is more than a little insane. But so are crypto nuts, so we'll see.

https://www.youtube.com/watch?v=U-N-pFG_oo0

Comment Re:If anyone still thinks... (Score 1) 518

I was reading yesterday about how the vast majority of Americans believed that Jane Fonda, after having been given notes from American POWs in Vietnam, handed those notes to their North Vietnamese captors. It was never true, but pro-war Republicans wanted to discredit a leading anti-war celebrity- so they made up a bullshit story about her and repeated it often enough that everyone believed it.

This was before Fox News and before Ronald Reagan. Republicans have always been like that.

Comment Re:If anyone still thinks... (Score 0) 518

"I have a dream that my four little children will one day live in a nation where they will not be judged by the color of their skin but by the content of their character."

-Martin Luther King 1963

What you're calling "bigoted prejudice" is really just decent people judging you by the content of your character.

Comment People have been complaining about helldesk (Score 1) 116

for years. Apple, Microsoft, Google, all of them Have Issues. Smaller, more nimble, companies may be more easily contacted, but it often takes knowing someone who can bypass the various gatekeepers.

And not just in software. Several years ago I had a highly repeatable weird glitch while closing the top of my German convertible. Couldn't seem to get it fixed. Complained to Warren Brown (RIP) at the Washington Post during an online chat, and two days later I got a call from a regional engineering guy at the car company, and was in that weekend getting a switch replaced.

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They laughed at Einstein. They laughed at the Wright Brothers. But they also laughed at Bozo the Clown. -- Carl Sagan

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