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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.

Submission + - Leaked Documents Show What Phones Secretive Tech 'Graykey' Can Unlock (appleinsider.com)

AmiMoJo writes: Leaked documents reveal the secrets behind Graykey, the covert forensic tool used to unlock modern smartphones, exposing its struggles with Apple's latest iOS updates. Graykey is a forensic tool designed to unlock mobile devices and extract data, primarily used by law enforcement agencies and digital forensics experts. Graykey supports Apple and Android devices, though its effectiveness varies depending on the specific hardware and software involved.

A leak of some Grayshift's internal documents was recently reported on by 404 Media. According to the data, Graykey can only perform "partial" data retrieval from iPhones running iOS 18 and iOS 18.0.1. These versions were released in September and early October, respectively. A partial extraction likely includes unencrypted files and metadata, such as folder structures and file sizes, according to past reports.

On Google's Pixel lineup, Graykey can only partially access data from the latest Pixel 9 when in an "After First Unlock" (AFU) state — where the phone has been unlocked at least once since being powered on.

Comment Re:Competition (Score 1) 268

He's... not wrong.

We should be really scared of people who are excited about finding ways to kill people we (or our allies) are in conflict with, but they're a necessary evil as those people exist on the other side of the conflict.

They are weapons, ideally to be controlled by more measured and compassionate people, and deployed in self-defense against people who aren't quite so restrained.

For instance, the people finding new ways to kill Russian troops in Ukraine. They're getting lots of people killed, but it's justified because Russia invaded and started indiscriminately killing a lot of innocent people.

Like the Training Day quote...

"To protect the sheep you gotta catch the wolf, and it takes a wolf to catch a wolf."

Comment Re:NIST is right and wrong (Score 1) 180

However, requiring mixed case and special characters? If you give that up you drastically reduce the difficulty of dictionary attacks. You double the size of the required table by using mixed case, triple it with special characters.

Nope. Most people, when they are "required" to use mixed case and special characters, do it in a way that can be easily brute forced with only a handful of extra attempts (1 = !, at = @, O = 0, etc.). The parts that preserve the difficulty of brute force are:

  • 3. Verifiers and CSPs SHOULD accept all printing ASCII [RFC20] characters and the space character in passwords.
  • 4. Verifiers and CSPs SHOULD accept Unicode [ISO/ISC 10646] characters in passwords. Each Unicode code point SHALL be counted as a single character
  • when evaluating password length.

  • 9. Verifiers SHALL verify the entire submitted password (i.e., not truncate it).

Web site have been having it both ways for years: they have been telling us to make harder password, while simultaneously making it harder for us to do so. In some cases, passwords were truncated or forced to lower case before being hashes, making them much much weaker than it seemed they were. And then when a password is compromised, the user is blamed.

Don't mix up the actual strength if voluntarily using complex passwords with the perceived strength of forcing someone else to do so.

Comment Re:Motive (Score 2, Informative) 51

... it would seem that Iran is more afraid of Trump than Harris.

Actually they're angry that Trump had Qassem Soleimani killed.

It's kind of funny. The Russians hack the Democrats, the Iranians hack Trump. The Russians and Iranians are practically allies. They should probably schedule some collaborative hacker meetings to make sure they're on the same page.

Comment Re:Google denied Stadia's cancelling too... (Score 2) 17

...shutting down its Stadia game streaming service this summer

That's just what I was thinking. They said the same about Stadia, and yet it was canceled. To be fair, they didn't do it in the summer, but I think it's fair to say that Fitbit's days are probably numbered. Especially after all the feature removals that Google has been pulling with Fitbit.

Comment Re:No, that's not their problem (Score 1) 28

Their problem is they have no serious path to long term profitability.

That is the right answer. Reddit cannot rely on growth anymore, not at this point. And it's certainly not profitable in its current form. Warning about a bunch of "troublemakers" messing with the price is ignoring the giant iceberg ahead.

Comment Re:Power (Score 1) 54

Microsoft has announced an atomic energy station to power its AI needs.

You're not wrong. Maybe AI will be the thing to bring Nuclear back in favor? https://ancillary-proxy.atarimworker.io?url=https%3A%2F%2Fwww.theverge.com%2F2023%2F9%2F26%2F23889956%2Fmicrosoft-next-generation-nuclear-energy-smr-job-hiring

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