Comment Close (Score 1) 124
1078 years does sound really short.
Comment Actually refutes? (Score 1) 29
Do you mean "refutes" or just "denies"?
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 Simple answer (Score 4, Interesting) 125
I've passed on loads of older PCs and laptops to non-tech-savvy users. I simply install the latest Debian, set it to auto-update, add a couple of shortcuts on the dock and away they go. Most of them aren't even aware that they have a different operating system apart from the fact that it gives them far less trouble. All they want to do is access the web and their e-mails and compose the odd letter.
Comment Rolling 25 years (Score 4, Informative) 47
So no change there then. Nuclear fusion has been a rolling 25 years away for decades.
Submission + - C++ Standards Contributor Expelled For 'The Undefined Behavior Question' 23
suntzu3000 writes: Andrew Tomazos, a long-time contributor to the ISO C++ standards committee, recently published a technical paper titled The Undefined Behavior Question . The paper explores the semantics of undefined behavior in C++ and examines this topic in the context of related research. However, controversy arose regarding the paper's title.
Some critics pointed out similarities between the title and Karl Marx's 1844 essay On The Jewish Question , as well as the historical implications of the Jewish Question, a term associated with debates and events leading up to World War II. This led to accusations that the title was "historically insensitive."
In response to requests to change the title, Mr. Tomazos declined, stating that "We cannot allow such an important word as 'question' to become a form of hate speech." He argued that the term was used in its plain, technical sense and had no connection to the historical context cited by critics.
Following this decision, Mr. Tomazos was expelled from the Standard C++ Foundation, and his membership in the ISO WG21 C++ Standards Committee was revoked.
Some critics pointed out similarities between the title and Karl Marx's 1844 essay On The Jewish Question , as well as the historical implications of the Jewish Question, a term associated with debates and events leading up to World War II. This led to accusations that the title was "historically insensitive."
In response to requests to change the title, Mr. Tomazos declined, stating that "We cannot allow such an important word as 'question' to become a form of hate speech." He argued that the term was used in its plain, technical sense and had no connection to the historical context cited by critics.
Following this decision, Mr. Tomazos was expelled from the Standard C++ Foundation, and his membership in the ISO WG21 C++ Standards Committee was revoked.
Comment Fairly normal (Score 2) 57
The space equivalent of the hand reaching out of a car window and casually dropping a McDonald's box.
Comment Tricky (Score 2) 58
Now they need to find not only a replacement chip of the same type but also a field service engineer willing to go out on a Saturday.
Comment Aaaargh! (Score 2) 131
Two megawatts of energy Doesn't anyone proofread this kind of thing?
Comment Pics or it didn't happen! (Score 1) 187
EOM
Comment Re:Get mugged in luxury (Score 1) 98
Yes, I can see that having people fail to queue in an orderly fashion for the train would be even worse than being mugged.
Comment Re:Get mugged in luxury (Score 5, Informative) 98
Clearly you have never been on a French train - much less a TGV. They are very comfortable and pleasant and the French on the whole are civilised people.
Comment Probably not just Paris (Score 5, Informative) 98
I doubt it will "premiere on the Paris rail network". There would be no point in a TGV if it just ran around Paris. Their whole purpose is to cross France in as short a time as possible and the French government aims to eliminate short-haul flying in France.
It might premiere on routes to and from Paris, but then most TGVs are on those routes anyway.
Comment Re:Summary misses the most important thing: (Score 1) 51
The ROM chips, certainly on the early machines were just in the address space same as the ram and ran at full speed.
Is that right? Whilst they were certainly in the same address space ISTR that the ROMs ran at only half the speed of the RAM. One speed-up technique was to copy crucial bits of the ROMs into RAM.
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