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Submission + - Another large Black hole in "our" Galaxy (arxiv.org)

Submitted by RockDoctor
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

Submitted by AmiMoJo
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.
User Journal

Journal Journal: It is 2025 and Slashdot doesn't support IPv6?

Journal by grub
I've been migrating all my stuff to IPv6 because I'm retarded and felt like (another) winter project.

So I have a Debian VM that is IPv6-only for testing things out, general browsing, etc. and see that Slashdot doesn't support IPv6? One would think a tech site would have been onboard with this years ago.

Comment Re:Modern security products seem to increase... (Score 2) 30

by QuantumFTL (#64801121) Attached to: 1 In 10 Orgs Dumping Their Security Vendors After CrowdStrike Outage
I don't necessarily disagree with where you're going here, but can you elaborate on this:

The whole world has realized that they need to start air-gapping databases

I've worked at government contractors that had real air-gaps for things like their databases, but that does not seem to be the norm for the rest of the world. How would ordinary businesses make use of their databases if they are not network accessible under any circumstances, printed reports? Some sort of unidirectional transmission? What sort of data ingress are they using?

I ask this because I have been involved in the transfer of data in highly regulated, air-gapped systems, and they are incredibly expensive. Are you really indicating that true air-gap databases will be ubiquitous (or at least commonplace) in the forseeable future?

Comment Is this a surprise? (Score 3, Insightful) 18

by QuantumFTL (#64400024) Attached to: Framework's Software and Firmware Have Been a Mess
It's a cool idea and they stand for a lot of great ideals, but laptops are incredibly hard to get right, drivers are hard to get right, and they are a small team trying to support a large number of possible configurations. Hardware gets more complicated by the year: forget the CPU and various GPUs, just look at how many other devices in a modern computer have a full-on processor, e.g. fancy touchbars, displays, even hard drives! Hell, your CPU probably has its own secondary general-purpose processors for things like security, and our CPUs themselves get firmware updates now to change how their instructions function. They are doing great work, but the deck is so stacked against them that it's not funny.

Comment Musk should thank his lucky stars for this (Score 5, Interesting) 222

by QuantumFTL (#64374238) Attached to: Biden Takes Aim At SpaceX's Tax-Free Ride In American Airspace
Most space launch companies are inefficient and ineffective. SpaceX has the margin to pay these taxes, those unfortunates don't. If you want to kill competition in an industry, tax it enough that only the large corporations can survive the loss, and add some complicated regulations in for extra effect. No one else has anything close to what Starship may become, and further reduction in margins will ensure that SpaceX will have a defacto monopoly on non-military space launches while their competitors are strangled paying for FAA services that is disproportionately benefit owners of private jets and charter flights for the rich.

Comment Hal Finney was Satroshi (Score 4, Interesting) 91

It has been an open secret in the cryptography community that Hal Finney was the designer of BitCoin from the very start. Hal died in 2014. Or at least he was frozen in liquid nitrogen so not talking either way.

Besides being the first person to be involved in BTC who didn't hide behind a pseudonym, Hal published a paper that describes essentially the whole BitCoin scheme two years before BTC was launched. And Hal never once accused Satoshi of stealing his work.

The reason Hal had to hide behind Satoshi is simple: The Harber Stornetta patent didn't expire until about 9 months after BTC launched. That covers the notion of the hash chain. There is absolutely no way anyone working in the field did not know about that patent or its imminent expiry. Hal certainly did because I discussed it with him before BTC was launched.

So the big question is why BTC was launched when it was, why not wait 9 months to have free and clear title? Well, Hal got his terminal ALS diagnosis a few weeks prior: He was a man in a hurry.

Having launched prematurely, Hal had to wait six years after the original expiry of the patent term to avoid a lawsuit over the rights to BTC from Surety. He died before that happened.

Oh and I have absolutely no doubt Hal mined the genesis blocks straight into the bit bucket. The key fingerprint is probably the hash of some English language phrase.

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