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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:Space is hard (Score 1) 32

>SpaceX rockets failed repeatedly before getting it right

They didn't, though. There is a HUGE difference between test flights and production flights.

Falcon 1 scheduled several test flights. This where test flights, designed as such, and carrying accordingly mass-simulators, broken satellites, or a bloody wheel of cheese. Their first few failed, which was expected, and not a concern, as this are test flights. Then they reached orbit succesfully, and so they went into production. Their next flight was a production flight, and worked flawlessly too.

Then Falcon 9 came, which worked flawlessly on their first flight, and flew flawlessly for 5 straight years. They had ONE in-flight failure with 1.1, then absolutely none since FT. So 8 years of flawless launches, almost 200 of them too.

Comment Re:Cheap, efficient on-demand launch. (Score 3, Interesting) 32

Virgin Orbit offers expensive, inconvenient, unreliable launches.

For instance, Electron costs *half* of what a LauncherOne will cost you, and RocketLab is more reliable, has more launches under their belt, and offers a fantastic truly customer-oriented system.

The supposed advantages of air-launch aren't such. First of all, it's for the most part a lie. "It's just a plane, so we can launch anywhere". Well, except you do need pretty much all facilities except for a launch tower at your airport. And you need authorizations from everyone, from the FAA to the airport itself, local authorities, etc. Launching from another country? Even more bureaucracy. And it'll only be ok if it's a NATO country and the US gives the Ok for it (because ITAR). So all of those advantages evaporate fairly quickly.

If you want cheaper, and your orbit allows it, you can get on a SpaceX ridesharing mission. Anywhere from 300k to around 2 to 3 million for the max payload capacity that LauncherOne can handle. And you're launching on the most reliable rocket in history.

The problem with their last launch is a fundamental flaw, not necessarily on design, but on how they do things. Their processes are horrible. Sure, they aren't the same company as Virgin Galactic now, but they used to be, and they obviously inherited the same culture.

VO was already not very appealing, but now there are even more options, and more are coming. VO hasn't gone the way of Astra yet for the same reason BO isn't out of business: A big ego with big pockets behind it.

Comment Re:I don't understand why anyone is working on thi (Score 1) 40

Generally, I agree with your sentiment, but also "letting them get away with it" is a bad precedent. We've already seen similar efforts from microsoft, and from other manufacturers. Apple isn't the first, nor will be the last, to try and lock down a platform.

Breaking whatever BS protection they throw at it and doing what you want with the platform is exercising your right to use your own stuff however the hell you want. It's like the US flying over what China claims as the South China Sea. Basically, use it or lose it.

Comment Re:It's "Crew 6", not 6 crew. (Score 1) 45

That is correct. The first mission to carry humans for NASA wasn't a production mission, and so it was called Demo-2 (after Demo-1, which did everything but without people onboard). After that, Crew 1 through 6. So it's the 7th mission *for NASA*. In addition, they also flew Axiom 1 and Inspiration 4.

So, 1 manned demo mission, 6 missions for NASA in the main contract, "Crew" series, 1 for Axiom, 1 private, for a grand total of 9 missions with crew onboard so far.

Comment Re: Big government at it again (Score 1) 89

All of which would improve almost immediately with competition.

I have posted here for maybe five years. But I felt a twinge of nostalgia, so I decided to check out the latest headlines.

So I see this headline and I go: This is totally crazy, so nothing has really changed about the world during my absence.

So then I see your comment and I go: This is totally crazy, so nothing has really changed in the discourse, either.

The competition-porn security blanket was a cute idea back in the early 1980s. I was there when the Apple II, the TRS-80, and Commodore Pet were busy trying to set the world on fire. And I've watched the evolution of this space very carefully ever since. As a blue-blood digital native it's the main story of my life and times. My fascination with digital electronics began in the early 1970s. My attitude when the original home-computing toys arrived wasn't: Where did this come from? No, it was: Where have you been all these long, painful, pining year?

This was all supposed to set the world free. That's the story we always tell entering into a new age.

What do I see around me now? Five or so trillion dollar corporations dictating nearly every damn thing about this technology is developed, how it is delivered, and how it is consumed.

This is the house that competition built.

What were these companies competing for all these long years? What was the final brass ring? I'll tell you, and it should be obvious: To gain the monolithic scale to collect monopoly rent not just from their products, but also from the very context in which those products are rendered relevant to our psyches.

Sure, competition is a magic growth hormone, considered narrowly. But surely there's enough water under the bridge at this point that "considered narrowly" ought to be consider harmful. No?

So let's step back and not consider competition narrowly. What are the systemic realities of naive faith in competition?

The systemic reality is that competition injected at the bottom (a good thing) merely kicks the can down the road. The corporations then compete to rise above the discipline of competition. Maybe we double down and inject competition again, this time bigger, purer, bolder than before. Then the cycle repeats again. This time with even bigger corporations competing to rise above competition as titans, behemoths, and leviathans.

Is the government succeeding at taming these giants? Do Google, Amazon, Apple, Microsoft, and Facebook practice all that much legitimate competition? Here's a skill-testing question. Which of those five corporations is not known for commanding a primary vertical? Google has search and YouTube and the gated Android store. Scratch one. Amazon has AWS and the gated Kindle store. Scratch two. Apple has the iPhone and the gated iOS app store. Scratch three. Microsoft has government workflow integration and the PC gaming community. Scratch four. Facebook has social. Scratch five.

Even to define these verticals as duopolies requires athletic feats of imagination. I happen to use YouTube as my main social platform, and I've never had an account on Facebook. Do I strike you as a typical consumer? Or the 1% of the 1%?

I'm not just speaking here in cliche. I'm extremely well versed on free market principles, free market principles, and the theory of systems, including economic systems and human discourse systems. I spent over 500 hours consuming neoliberal podcasts featuring every possible flavour of neoliberal guest.

On a parallel track, over the past year I traced pretty much the entire evolution of postmodern thought from Hegel and Marx forward to the present times. There's actually quite a lot of neoliberal theory I'm sympathetic toward. I wish I could say the same for postmodernism, but that's another can of worms.

I like much of neoliberalism, but I'm not stupid. I can see the world plainly as it exists plainly before my eyes. We injected competition, it was wonder and vigorous for many decades, but finally and we got was monopoly on a larger scale than we've ever seen before.

What do you suppose the host talks about after conducting over 500 hours of interviews with hundreds of different guests, on mostly the same small set of topics?

Here's an eternal theme: If only we did it right, this time.

You see, every attempt to reform the world that lead to the world remaining the same as ever, only more so, shared the same universal flaw: We didn't go big enough to make $purity cure $horse. This is the one true universal excuse. It was used for socialism. It was used for market capitalism. It was used for every darn thing in between.

So the silver lining in creating worse monopolies than we've ever had before is that we forced them to make us a lot of nice toys in getting there. So I guess we have actually reformed monopoly to some degree. Once upon a time, monopolies came into existence without hardly making anyone a new toy worth having.

Okay, so what's another topic that burns eternal when you discuss the same small set of neoliberal principles for 500 hours?

Education reform. Sound familiar? It surely must. You see to be an expert, with an expert diagnosis, which in your unique genius you've managed to distill down to one word. Competition. Quite the magic trick there, I must say.

Here's a small thing. Charter schools, as normally implemented, are yet another government program. It's a government program with an extra degree of freedom inside compared to the normal landscape. But it's still a government program.

How do Charter schools mainly compete? For the quality of the parents. They often say that they are neutral. But then the application process is so arduous, that only the most truly devoted 1% of parents make it all the way through. So many meeting you have to attend with the school admissions people. What kind of family can organize that? Either a family with means, or a family with fervent devotion to the educational cause.

The vast majority of superior Charter school outcomes comes from this factor alone. Education concerns human capital. Nothing improves human capital like a sorting hat that selects only the right people, for whatever metric you wish to optimize.

Actual value-add in education has mostly proven to be a long unicorn hunt. You can figure out who your best students are easily. No matter how you teach, your best students will remain your best students. For the rest of your students, things are far more hit and miss. One teaching method might connect with one student, whereas a different method might connect with a different student. Neither of these were A students to begin with. And rarely do they become A students at the end. (There are of course some spectacular exceptions if you pray at the alter of N=1.)

Because building a school with better human capital is so much easier than improved the human capital you're stuck with, almost all the best charter schools have mostly done the former. Mostly. There are marginal gains to be had by getting the rest right. Marginal.

So what happens? The schools get good at lying about the reality that they are competing for human capital, and make a big story about how they've improved the capital of their students during their time at the school.

I think it's Finland that has gone furthest in education reform. This was also a competition for human capital, but they moved this into the teaching ranks, rather than the student ranks.

Education is very nearly the hardest degree program in Finland to get into. It would be maybe a small step down from medical school. Dullard teachers in Finland are rare birds. The students have far less class time, are given far less formal homework, but they work hard anyway, and consistently score highly in the world tables.

South Korea does everything exactly the other way. Stories are written about high school students in Korea jumping out of windows. After you sleep through most of the official school day, off you go to the second, private sector school day. And all they ever graduate are narrow technocrats. It's a disaster on wheels.

Blowing smoke up the ass of competition sure beats having to know something about the real world. Makes you sound smart, without typing your fingers off, like I've just done.

Which is why I finally moved on from Slashdot to greener pastures.

Comment Re:Let's have everything controlled by software (Score 1) 23

Not to mention no dedicated hardware LED to indicate that the microphone/camera sensors have been switched by software into an active state. I generally keep my phone inside it's leather sheath and not in the same room. Close enough to reach in a few steps if it beeps, not close enough for rogue candid camera.

Comment doublespeak (Score 3, Interesting) 46

No one who actually cares about their privacy is using Chrome anyway.

You've missed the entire ball of wax. People care about privacy, but they get systematically priced out of the conversation.

People who "actually" care is just doublespeak for those who are too stubborn to allow themselves to get priced out of the conversation.

I've been immersed in the software profession since the 1970s. I once won a math prize. I even won a writing prize. I spent much of the 1990s reading Applied Cryptography for light entertainment. I understood that there ought to be side channels in the time domain concerning caches and speculation long before these began to emerge. (Peter Wright's book from 1988 had already impressed upon me that exploitation of side-channels was a going concern.) I figured that smarter people than me must have poked into this, so it probably wasn't as bad as it appeared to be. I was wrong. If anything, it was even worse than I intuitively suspected.

In summary, I have all the cognitive tools in the world, and security still makes my head hurt. To "actually" care is a Sisyphean standard in the modern IT landscape.

"Just" install Firefox. Seriously. That's the full cure?

If you can even do that much. I have family members who work for the government. They are only allowed to use Edge, which just Chrome with an additional layer of sheepskin, draped over top of a wolf with twice as many teeth. So they drive Edge for 35–45 hours per week at the office (only one of my four family members lucked into the nearly mythical short government work day) and then they come home to drive something completely different, just to show that the "actually" care about their privacy.

If greater society actually cared about people actually caring, then the government IT environment would permit the use of alternative browsers, at least within reason. Greater society does not actually care about people caring, so this is entirely verboten.

Unless this: German state planning to switch 25,000 PCs to LibreOffice — 18 November 2021

How long did that last in Munich, at the other end of Germany?

LiMux was a project launched by the city of Munich in 2004 in order to migrate from Windows to a desktop infrastructure of its own, based on Linux. By 2012, the city had already migrated 12,600 of the total of 15,500 desktops, until in November 2017, the Munich City Council resolved to reverse the migration and return to Microsoft Windows-based software by 2020.

The LiMux lead on Wikipedia used to also include this sentence:

The city reports in addition to gaining freedom in software decisions and increased security, it has also saved Euros 11.7 million (US$16 million).

Now you can only find it burried deep in a ==Timeline== section, as a single line item:

23 November 2012 — Savings from LiMux environment over 10 million euros.

Ironically, there's a copy edit flag on the entire section stating that "this section is in list format but may read better as prose".

Am I going to sign up for the apparently Sisyphean task of keeping that comment about security and privacy and savings prominently displayed in the LiMux article lead, where it belongs? No, I'm not. Because I "actually" don't care, according to your doublespeak usage of the word "actually". Because to "actually" care is to have infinite resources in all directions and no concern whatsoever over painting yourself thin.

Comment Re:What a difference that'll make (rolls eyes) (Score 1) 98

give the user something to do while loading in the background

Something more productive than minesweeper?

Is this principle oriented toward true productivity, the cult of merely looking busy, or the need for constant distraction felt by those living lives of quiet desperation?

Comment Insanely stupid (Score 1) 108

Here's the first AUDIT question from GDS 2021 Global Report

How often do you have a drink containing alcohol?
* Never
* Monthly or less
* 2 to 4 times a month
* 2 to 3 times a week
* 4 or more times a week

Approximating a year as 52 weeks divided in 12 months and converting to milli-drinks per day, the available ranges are:
* 0
* (0,33]
* [66,132]
* [286,429]
* [571,infinity)

THREE large discontinuities.

Doh!
Double doh!
Triple doh!

It's not even specifying standard drink volumes. If you drink from an old-fashioned jug balanced on a bent elbow, "one" drink could be as much as an entire gallon.

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