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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 Are they redistributing the material? (Score 1) 47

Copyright is all about copying and reselling(at any price) material. I don't understand what the big deal is, as meta is not reselling the material. It is digesting it and using it. Which is the same as any person would do when reading a book. As far as I can see there is no copyright infringement as they aren't reselling it.

Comment They've been incorporating AI into things (Score 1) 98

and it's not going well. For example the AI would create a description of the video, that gets many things wrong or misstates things, like "This guy" when it's a girl, or "The maker" when they are doing a disassembly of something.
Also it's adding in default comment replies, often complaining about the algorithm.

If their expenses have been going up it's only because of adding things that nobody wants.

Comment Re:Fairness (Score 1) 93

Would this project take open source projects under it's wing, and do things like provide corporate support, corporate dev (for the things that aren't interesting), maintenance etc. Would this be a way to
1. provide open source projects development money even if they aren't part of the post open world.
2. provide systematic methods of corporate sponsorship

Also would this be a new license, replacing other ones out there, (if so how would/could that happen with many developers on a single project). or would this be an additional license?

Comment Software services on hardware (Score 1) 64

I wonder how this would affect the following case.
Once upon a time I bought a cool clock from Sony that you could download cool faces and software that made it do different things.
Then sony shut down the servers.
Then my cool clock was just a clock with nothing special except an expensive purchase price.

Comment Elon ripping off Tesla shareholders. (Score 1) 70

Elon roled out AI at Tesla with great fanfare, talking about the DOJO and so on. Then he made an AI company that took resources that should have gone to Tesla. Now he want's Tesla to pay him for the AI company. That sounds like a great business plan. Maybe he shouldn't have gotten that stock compensation afterall.

Comment I watched 1/2 of it.... (Score 1) 94

then the power went out. Not sure if I'm going back. I thnk netflix needs better stuff. It seems all anime (cartoon person running and yelling in every fucking preview) Dubbed so badly it's unwatchable or just plain stupid "comedy" shows that aren't funny.
Starting to wonder why I subscribe.

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