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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 Anybody want to buy an old SGI workstation? (Score 2) 284

Anybody want to buy an old SGI workstation? No, seriously, there's on in my basement...

It is a shame there's no incentive for code dumps with at least zero liability and there's no mechanism for using things abandoned by the copyright holder and, more generally, that our copyright is so onerously long that the prior point matters. But... I'm not at all sure old workstations are in my top 10 important cases of software where that matters.

I still lament the outliner called "More" from around 1991 MacOS that I have still never found the equal of.

Comment One of those comments I hope is a troll... (Score 1) 114

One of those comments I hope is a troll... because that this is earnest would be pretty depressing.

You seem to be missing the general concept that the amount of anything matters. How about I give you a penny and you give me $10,000? Sound good?

Yes, you cannot create and drive around an electric car with inherently zero CO2 emissions. I have no idea how you jump over the idea that the gas car might have many, many, many MORE emissions.

There are several reasons electric and hybrid are inherently more efficient.

Maybe there is somewhere with horrendously managed coal power and extremely well managed ICE, but that seems unlikely.

Comment Kindof uncomfortable calling this mineralisation (Score 2) 114

This sounds great.

I'm kindof uncomfortable calling this mineralisation because this is a mineralisation-DEmineralisation technique. It dilutes the definition of mineralisation as an alternative way to store carbon with probably greater resiliency to leaks.

It's akin to equating e.g. nuclear power to hydrogen -- one is an originating source of energy for humanity that can't store it and the other is a way of storing energy that doesn't not source it. Maybe using hydrogen as a mechanism to store and distribute nuclear power makes sense, but any comparison between them doesn't.

(Hydrogen fusion would be, but everybody calls that "fusion" and not "hydrogen"

Comment Re:Do they even know what trolled means? (Score 1) 156

On the one hand, I don't think that's a very good definition of trolling. On the other hand that might be the best definition you could hope to plausibly classify things as in a regular research study, so maybe that's why they chose it. (Although of course even in general, "no reason" almost never exists; it's a question of who is doing the discerning, how far they can see, and how remote it is to whatever topic is at hand)

I'd describe classic trolling as something like: communication whose primary intent is covertly eliciting an asymmetric negative emotional situation for others with disregard for the personal authenticity of the communication. Most commonly this is also an asymmetric investment (a large response compared to the trolling) saying things the troll doesn't even particularly believe, and the negative emotional situation is frustration and exasperation that can sometimes border on anger, usually community-viewable. I don't think it requires true intent so I would also include "for no reason" -- any communication consistent with that intent unless it shows clear evidence of alternative rationales.

There are several things it's not, at least to me:

2) conventional bullying and/or personal attacks. This is almost by definition overt rather than covert. [Often it seems it does have a reason too, but that's murkier.
  ]

3) Any means to a discernible end. e.g. Trying to draw out someone's authentic responses to primarily show the community truth about them -- perhaps to publicly uncover lies or inconsistencies or unpopular positions to lower the social status of that person. I think it has to be about generating their emotional reaction for its own sake. Provoking a bully to show they are a bully is, instead, a means to an actual end.

4) It's common to have SIWOTIS (Someone Is Wrong On The Internet Syndrome) where you have a strong tendency (perhaps some compulsion) to try to correct people who are egregiously wrong about something and you perceive have some hope that you can convince them to come around to the "correct" position. This makes a lot of sense if this correction is "please don't drink gasoline" but isn't limited to that. This is the easiest way to become a troll VICTIM because it's the easiest thing to exploit: Just strongly assert something concrete that's very wrong.

5) There are a lot of versions of attempting to have topical discourse that can start to look a lot like it, but I would disqualify anything that is using earnestly held beliefs.

5a) Discussing random topics on the internet that perhaps have no practical value and seem like a waste of time... describes a lot of the Internet. They're not calling that trolling, but for context I'd argue the "no reason" part would still apply here.

5b) Doing the above, it's relatively easy to end up in an argument with a stranger on the internet, even quite accidentally, because you're saying things in front of many strangers without a lot of historical context about who each other are or a lot of present context about what's going on right now. I would not consider this trolling, just a common red herring.

5c) And of course even you didn't do it explicitly it's certainly even easier to end up in an escalating argument if you have unmanaged anger issues or are a bully etc. That's being an assh*le, but I would not consider it trolling.

Comment Bell & Howell (Score 1) 523

Way back when, Apple hadn't yet established relationships with public schools. School administrators didn't know how to classify computer equipment, anyway. The Bell & Howell company came to the rescue: they were vendors of audiovisual equipment like film projectors. Bell & Howell agreed to let Apple use their connections with school districts in exchange for the computers being rebranded as Bell & Howell equipment, in Bell & Howell livery.

This is why the first computer I ever got time on was an all-black sleek Apple II+ that looked like it belonged on the Death Star.

The original Bell & Howell Apples are now almost completely forgotten about. But man, do I ever have fond memories of them.

See one for yourself here.

Comment Re:Egregiously misleading quote; don't believe it (Score 1) 392

Personally I don't really understand anyone who is anti-nuclear in a world where we still burn coal, throwing literally more radiation into the air not to mention everything else. Leading visionary climate scientists like James Hansen support nuclear and it's even more true as we become more and more literally on fire.

And the article discusses all that in reasonable ways...

Comment Egregiously misleading quote; don't believe it (Score 1) 392

The crop of the quote is egregiously misleading. It wildly distorts the summary of the linked article to give it an anti-nuclear bias the article absolutely does not have.

The way this is clipped implies that der spiegel is saying nuclear power is immoral.

The very next sentence in the linked article is "However, some people believe nuclear power is both ecologically and morally sound " and they then proceed to discuss that. This quote isn't stopping at the end of the article's summary or even a new section -- it's just clipped to mislead.

-----
Someone could have a reasonable discussion about the value of nuclear because values are subjective. But this summary is objectively wrong -- it objectively does not portray the der spiegel article is purports to summarize.

Even if you somehow think nuclear is not an improvement in stopping climate change... you're not making a very good argument by misleading quotations.

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