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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:Plex = Subscription-Ware (Score 1) 69

I don't think it directly supports remote streaming

It does, but you'll need to route the incoming traffic through manually. For me, that involves having the router forward traffic on port 443 to the server and configuring a reverse proxy on the server to hand off traffic addressed to jellyfin.$HOME_DOMAIN to the Jellyfin daemon. In my case, Jellyfin is one service among many on a Docker host, with Caddy directing incoming traffic to wherever it needs to go.

It's not automated like Plex, but I've streamed movies and TV shows from across the country without any problems.

Comment Re:Cannot wait... (Score 3, Informative) 159

I used to screen scrape jail registry records for county jails in my home area. Though the IDs weren't exactly sequential, doing groups of 50 would get hits for two of the local counties.

What I found was that, while the website UI wouldn't show juvenile records, you could access them directly w/the ID. Surfacing it to the county took a day or so to find the right person but they quickly closed that hole, but who knows how many records were handed out to malicious actors over the years before I found it.

Comment Re: Nice Speeds (Score 1) 32

I recently switched my service plan (with Cox in Las Vegas) from 500 Mbps with a 1.2-TB (IIRC) monthly limit to 250 Mbps with no limit. After a couple of months of overages that basically doubled my bill, it'll be nice to have predictable billing no matter how much we end up using. 250 Mbps has been fast enough so far.

Comment Re:Plex (Score 1) 25

Plex is available on many more devices. Jellyfin has PC, iOS, Android, AppleTV, AndroidTV, Roku, and LG TVs. But Plex also has PlayStation and Xbox, Samsung TVs, Vizio TVs, and many other smaller streaming boxes.

I used to run Plex. I even paid for a lifetime subscription years ago. I now run Jellyfin; it's been less of a hassle to keep it running and it puts less load on my server. I shut off my Plex container last month after switching my parents' Rokus over to Jellyfin. At home, I switched to Chromecasts (the newer ones that run Android TV) after having run OpenELEC on Raspberry Pi 3s for a while.

Plex also has better remote access support. Just enable it and setup a port forward/firewall rule. Jellyfin? Have fun configuring a VPN on each client to access it.

My Jellyfin instance shares a box with a bunch of other services. Caddy routes traffic on port 443 wherever it needs to go: to Jellyfin, to one of the *arrs, to Nextcloud, GitLab, etc. One rule at the router passes inbound port 443 off to Caddy. No VPN is necessary.

By comparison, there were more than a few instances where Plex's "it just works" networking configuration didn't just work.

Comment Re:Minimalist tiny house neighborhoods (Score 1) 76

We already know how to build cheap high density housing with shared resources: Motel 6.

Shared bathrooms are not ideal. Every unit needs its own full bath so people can keep themselves clean.

A bed and a space to work are sufficient. Basically, a one-bedroom apartment minus the kitchen. The kitchen should be a community resource with staff like is done for public schools.

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