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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:not sure how this is a "near miss"? (Score 1) 82

I paid my property taxes online and got a receipt for it. They never took it out of my account, nor did they send the money to the county. I never noticed it. The county sent me a bill with a late fee. I finally got the late fee removed, but it was a pain in the butt.

Let me tell you, nobody at certifiedpayments.net had a single care about that late fee. It was only because the county was "nice" that the late fee was removed, and they made it clear that they didn't think they had to, they just thought it kinda felt right.

Comment Re:They come right out and say it (Score 1) 164

How do you scan a QR code if you break your phone? At least even non-smart phones could get text messages. And to answer your question, you get several passkeys. If one quits working, you user your backup. One service gave me a set of one-time-use passwords.

Passkeys are The Shit.

Comment Re:Wait, doesn't Microsoft own OpenAI? (Score 4, Interesting) 21

I use DuckDuckGo for about 90% of my searches. DuckDuckGo uses Bing for its results. It does just fine about 90% of the time. If I'm not getting the results I think I should get, I go to google.

So, yeah, while admittedly small, DuckDuckGo stats are still impressive to me:

The search engine is predicted to serve over 30 billion private searches in 2023. Its user base now tops 100 million worldwide.

Comment Re:Do Apple next (Score 1) 24

Apple certainly has a monopoly over it's app store. And the monopoly company is much more open with it's app store.

I stopped using Amazon's app store because the apps didn't get updated as frequently as they did on the Play store. At least it was an option. I've never used it, but it looks like Samsung has an app store, too.

Comment Do Apple next (Score 1) 24

I'm a little perplexed by this. I used Amazon's app store many years ago. I see it's still a thing: https://www.amazon.com/gp/mas/...

Find something even remotely close to the Amazon app store for an iOS device. Or, the ability to even sideload apps on an iOS device. OK, I know that is supposed to be in the works, but I've been hearing about it for a while now. I still haven't seen it actually working yet.

Comment Re:FCC (Score 1) 69

> Meanwhile the government spent $42 billion on rural broadband and still haven't connected even one person

What? I live out in the middle of nowhere, and I got fiber to my door this year, courtesy of a federal grant. And writing the words, "I have fiber to my door" is something I NEVER thought I would be able write.

Comment Re:Might run afoul of laws (Score 1) 221

I could see a good use of this being to lower prices during off peak hours in order to shape foot traffic a little better. If they use it to jack up the price for surge pricing, they will lose as much of my business as humanly possible.

So, discounts to encourage a better customer experience == good. Price gouging to just be price gouging == bad.

That's my two cents.

 

Comment Re:Where did Oracle get the info in the first plac (Score 4, Informative) 15

Let me DuckDuckGo that for you:

The suit accuses Oracle of collecting the data in various ways, such as through the use of its BlueKai tracking cookies, and then selling the information directly or through its “ID Graph” and other related products and services derived from its data.

More detailed info on BlueKai here (it was a company they bought):

https://techcrunch.com/2020/06...

Comment Re:Question for Windows users (Score 2) 100

I have a work account tied to an Office license. That's the only one I use frequently. All the others I only use when I have to login to do something. For example, when Microsoft had a nice forum for Asp.net, I would login to to post a question. They screwed that up so much that I now use Reddit or Stackoverflow.

I now have email through Zoho, Gmail, and Outlook that I use through a web browser. Of those three, Outlook on Edge is the only one that routinely stops downloading emails if I just leave it open all day in a browser window.

Good ol' Microsoft.

Comment Re:Hate this (Score 1) 134

I think no local account on Windows would be the final straw for me. I would switch to Apple. I mean, I have an Apple sitting right next to me. A few things I like about Windows better, but I could sure learn to live with an Apple if need be. I do have an account on Apple because I pretty much had to, BUT for some reason, I trust Apple more than Microsoft.

I used Linux on the desktop for almost a decade, but I needed to use Visual Studio.

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