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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:Wrong placement of speed warning (Score 1) 207

There's a model of car (an Audi I think) with a rear spoiler that only comes up when the car goes over fifty. The police loved them.

Porsche 964: https://www.elferspot.com/en/magazin/porsche-active-aerodynamics-paa/

Later, also the Audi TT (most models): https://press.audi.co.uk/assets/documents/original/23095-AudiUK00016101AudiTTSCoupéFullUKText.pdf

Probably others, but the 964 was the vehicle I remember most distinctly.

Comment No right? (Civil rights?) (Score 1) 692

Cullen White, AnitaB.org's chief impact officer, said in a video posted to X, formerly Twitter, that some registrants had lied about their gender identity when signing up, and men were now taking up space and time with recruiters that should go to women. "All of those are limited resources to which you have no right," White said.

I'm neither condoning nor condemning what any participant did, but I found this part (emphasis added) a bit ... Well. Given the various Civil Rights Acts in place in the U.S., e.g., the federal Civil Rights Act of 1964 2000e-2 and Pennsylvania's 1955 Act 222, both prohibit employment discrimination based on sex ... So kinda, yeah, they had a right. Whether or not it was appropriate for them to exercise it, I'm not going to dive into.

Comment Re:This has nothing to do with that. (Score 2) 692

As everyone these days like to say, gender is separate from sex.

Hell, my Con Law professor was saying that in '02, and I'm sure he'd been saying it for years.

We have no federal laws passed which protect gender or gender identity

Strictly speaking, that’s true. But. BHO expanded Title VII by executive order (see, e.g., E.O. 13988), to include “gender identity.” But that was in the wake of the SCOTUS ruling in Bostock v. Clayton County , 590 U.S.—(2020), expanding the statutory term “sex”to include “gender identity” (and sexual orientation). So while technically no federal statutes protect “gender or gender identity,”in practice, under Bostock (and of course various state laws; the most populous state in the country having, e.g., the Unruh Civil Rights Act, which expressly does protect “a person’s gender identity and gender expression [a person’s gender-related appearance and behavior whether or not stereotypically associated with the person’s assigned sex at birth].”

Comment Re:Open Datasheets When? (Score 1) 204

almost everything else, at least everything else that isn't a toy, has been using proper barrel jack connectors and DC/DC converters pretty much forever.

You're aware that basically every laptop coming out the past several years, from MacBook Air and Pro models to Lenovo ThinkPads (basically, anything but gaming laptops with power-sucking GTX GPUs etc) are using USB-C PD to charge, right? Current, widely available devices allow for 100W (20V @ 5A PDO), and up to 240W was standardized a couple of years ago.

Comment Re:Not smart... (Score 1) 207

It is known.

https://www.businessinsider.com/smart-tv-data-collection-advertising-2019-1

https://www.cnet.com/tech/home-entertainment/as-smart-tvs-become-the-only-option-your-privacy-choices-fizzle-out/

https://www.theverge.com/2019/10/11/20908128/smart-tv-surveillence-data-collection-home-roku-amazon-fire-princeton-study

https://www.wired.com/story/save-money-buying-dumb-smart-tv/

https://www.theatlantic.com/technology/archive/2023/01/smart-tvs-sony-lg-cheap/672614/

Comment Re:Good riddance (Score 1) 134

And I'm not talking about the codec. I am talking about the fact that you pretty much need iTunes in order to use the iPod. And they also had their proprietary charging port. 2 huge fails.

iTunes or ... Floola, or AmaroK, or gtkpod, or gPodder, or Rhythmbox (this is the one I use, to manage music on my iPod Mini, in Lubuntu), or aTunes, or Yamipod, or Banshee, or ...

The first iPods used Firewire, an IEEE standard: https://en.wikipedia.org/wiki/IEEE_1394

Later iPods used the 30 pin connector, which was pretty trivial to unwind (https://pinouts.ru/PortableDevices/ipod_pinout.shtml), and could be sourced from any number of sources. It's also worth remembering that, at the time, pretty much *every* device used a different proprietary connector (looking sideways at my old Palm Treo, Palm Pilot, Samsung and Motorola flip phones, etc), or had basic connectors (SanDisk MP3 player with a Mini USB B socket) that could *only* be used to manage the media, with no audio transmission or playback control etc.

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