Comment Re: All hail our new technocratic oligarchy (Score 1) 59
"the Clinton administration a year and a half ago" likely in much deeper now ðY
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.
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.
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 Data (Score 1) 38
So that's what happened to the missing govt datasets.
Comment I don't understand people (Score 1) 123
One of the more shocking public surveys I've ever seen found that the majority of people would not pay $100 to see a live dinosaur.
Now this thread is filled with comments against this project, from "frankenstein" to "why bother".
I truly don't understand people.
Comment Surprised (Score 1) 130
I actually agree with two - Jon Haidt presents some compelling insights and Grady makes fun YouTube videos
Comment Re:LOL well finally (Score 1) 77
>If they were they would have hired someone like RMS, or Bruce Schneier, or someone else with a history in the Open Source or Privacy movements.
Good point.
Comment Globalist power grab (Score 2) 268
Since climate change is, supposedly, a world-ending threat, there
is no limit to the power and resource confiscation it will justify.
Look forward to:
- UN deciding which industries are permitted to receive investment
- UN deciding which businesses are permitted to manufacture products
- A relentless flood of "climate refugees" into all western lands
This is regardless of the veracity of the climate change claims.
Comment Re:burning coal vs nuclear (Score 1, Troll) 268
>There are too many layers of grift and red tape.
Don't forget the inevitable nuclear melt-down sacrifice to DEI.
Comment Wrong dwarf planet (Score 1) 118
Hail Eris!
It's bigger than Pluto and Mike Brown found it at Palomar, not in some desert state where gila monsters and politicians compete for who can bite worse.
Comment Re:Looks slow to me. (Score 1) 78
Two modern techniques for building are SIPs (structural insulated panels) and ICFs (insulated concrete forms). Both methods involve foam insulation and also reduce the time to build. They're both just as costly, though. SIPs are constructed in a factory and the panels are trucked to the jobsite but exterior siding and interior drywall still need to be done on site. Stone and brick are great materials for longevity but are less energy efficient.
Comment Re: Weird (Score 1) 20
We blocked them a long time ago. They really are awful.
Comment Re: Looks slow to me. (Score 2) 78
There are channels built into the wall for wires to go through. Plumbing is typically through floors to avoid thermal bridging in the walls.
Comment Re: 100% blocked everywhere (Score 1) 20
Mastodon.social is still open to them afaik
Comment Re: Weird (Score 1) 20
That block was preemptive on a lot of instances. I know my admin proactively blocked them as soon as we knew what domain they would be federating from.
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