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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.

Education

University of Michigan Study Advocates Ban of Facial Recognition in Schools (venturebeat.com) 18

University of Michigan researchers recently published a study showing facial recognition technology in schools has limited efficacy and presents a number of serious problems. From a report: The research was led by Shobita Parthasarathy, director of the university's Science, Technology, and Public Policy (STPP) program, and finds the technology isn't just ill-suited to security purposes, it can actively promote racial discrimination, normalize surveillance, and erode privacy while marginalizing gender nonconforming students. The study follows the New York legislature's passage of a moratorium on the use of facial recognition and other forms of biometric identification in schools until 2022. The bill, a response to the Lockport City School District launching a facial recognition system, was among the first in the nation to explicitly regulate or ban use of the technology in schools. That development came after companies including Amazon, IBM, and Microsoft halted or ended the sale of facial recognition products in response to the first wave of Black Lives Matter protests in the U.S.

Submission + - Woz Turns 70th Birthday into Charity Event (wozbday.com)

NoMoreACs writes: Join Apple Computer inventor and co-Founder Steve Wozniak for "11 Days of Wozdom", a social media "Scavenger Hunt" featuring creative challenges that speak to the things he values most: Happiness, creativity, ingenuity and fun.

The challenges will officially begin on August 11th, but you can get a head start by going to WOZBDAY.COM for details.

The first challenge will be to help Woz spread the word about his birthday party and fundraiser on August 11th. All challenges will be due on August 21st at 11:59pm PDT. Challenge winners get special prizes!

Woz also stated:

"Iâ(TM)m lucky to be able to do this for a foundation oriented towards helping children, especially ones in need of finding themselves."

A livestream featuring a star-studded list of performers (see list at the birthday site) and other guests will begin on August 11, 2020 at 5 pm, PDT.

Come celebrate the life of one of the true pioneers in the Personal Computer Revolution. Listen to some music, hear some great stories, and maybe even help some kids in need!

Comment Late-Breaking News from the Council... (Score 3, Funny) 95

Early this evening, the Council of Elders announced a planetary day of mourning and magnanimity.

K'Nord, Speaker for the Council, spoke thusly:

"Citizens and Podmates, the Council is pleased to announce that after seven and a half full years -- the longest campaign in the history of the Martian Defense Force -- the diabolical mechanized adversary from the blue world has been defeated. Our defense forces, counted in the billions, have finally surrounded and denied the invader the light and warmth it needs to survive. The blueworlders have acknowledged defeat and ceased contact. Ths invasion, at least on this front, is now over.

Let us raise our glasses to mourn the lost gelsacs of at least half our press corps, some of whose entire careers have been dedicated to coverage of this conflict -- and in a spirit of magnanimity in victory, we -- the victors of the Conflict at Endeavour Crater -- must also raise our glasses in awe and respect of our longest-lived and most challenging foe."

Shortly thereafter, a wizened old retired Councilmember, his gelsacs having long ago been ceremonially ground into a fine tartare and shared amongst the Council, wiped a perchlorate tear from his eye: "Well-done, blueworlders. Well-done."

Comment Re:Seems like they don't have a "leg" to stand on (Score 5, Insightful) 502

because A) your luggage B) where did we lose this person C) we now have to delay the flight to make sure our count is correct. D) is there a security risk to the plane.

A) your luggage This trick doesn't work with checked bags, since airlines tend to check bags through to the final destination. Hidden-city travel is a strictly carry-on-only tactic.

B) where did we lose this person They know where they lost you, since they scanned your boarding pass when you boarded the first flight, and they didn't scan your boarding pass at the gate for the connecting flight.

C) we now have to delay the flight to make sure our count is correct This is the only potentially obnoxious consequence--some airlines may delay a flight by a few minutes to allow a "lost" passenger to get to the gate. But if an airline has a takeoff slot they're not going to give it up to recover one wayward traveller. And they do a headcount of passengers on board before every flight anyway--if it matches the count they get from the scanned boarding passes, they're good to go.

D) is there a security risk to the plane Nope. They know that you and your carry-on were on the first plane, but that makes you no more dangerous to that aircraft than any other passenger. They know that you're not on the second plane, since you and your carry-on never boarded. They know you don't have a checked bag in the hold.

Comment Re:Assumtions galore (Score 1) 336

I have no credit score because I've never felt like spending more than I have.

I have a credit score - a rather good one - but I've never spent more than I have. One does not have to carry debt to have a credit history.

Remember that a person is also being extended short-term credit even when they are paying off their balance in full every statement period. And that's not just the case with use of credit cards (which remain the easiest - and sometimes only - way to make purchases or payments in some situations). Thing about utilities like gas, water, electricity, cable, telephone, (non-prepaid) cell, internet...if you're billed at the end of the month after you've used the service, then you're being extended credit--and in many cases the status of those accounts will be reflected in your credit report.

Comment Re:Occam's Razor (Score 1) 1024

"Very few outside the US think US conservative media outlets are reputable"

And one significant reason for this is the relentless and universal portrayal of US conservative media outlets as disreputable by the US Leftist media.

I assume that your belief is informed by the restrained and nuanced portrayal of the US Leftist media by US conservative outlets. Ahem. (Incidentally, the "conservative" outlets seem to spend a lot more time talking about the "liberals" than vice versa.)

The non-US world has access to Fox just as readily as to MSNBC. In assessing reliability and trustworthiness, they've adjusted their Bayesian priors based on continuously supplied evidence about which networks give the most airtime to hypocritical, self-serving, lying sacks of shit.

Comment Re:Occam's Razor (Score 1) 1024

Seeing as 96 percent of google search results about Trump come from liberal media outlets

The figure in that article places Infowars as being just center-right, and the Koch-supported Reason straddles the left-right centerline.

If you draw your line that way, you're probably the sort of person who complains about reality's liberal bias.

Comment Re:comparison (Score 1) 172

How much would it have cost if NASA did it themselves ? I am also wondering if there isn't enough competition yet for this kind of thing.

It's an interesting question--what does it really mean for NASA to "do it themselves"? NASA has a very long history of contracting out the development and construction of launch vehicles. Remember, for the Apollo program the Command and Service Module was built by North American Aviation (as was the Saturn V second stage), the Lunar Module was built by Grumman, the Saturn V first stage (S-1C) was built by Boeing, the third stage was built by Douglas, the F-1 and J-2 main engines were designed and built by Rocketdyne.... I don't think anyone would dispute that the Apollo Program was a NASA project, but a great deal of the design and construction work was still contracted out.

The difference now is that NASA gets to choose its contractors after they've demonstrated their capabilities to build and fly the hardware. The "old" way was to decide in advance who got to have the monopoly and pay them to develop the technology; this "new" way involves choosing among members of a small oligopoly who already have the capability mostly off-the-shelf. There are tradeoffs - financial and planning - to either approach.

Comment The ratio isn't dumb unless the interface is... (Score 1) 411

A widescreen aspect ratio doesn't have to be dumb unless the people who design apps and interfaces refuse to make good use of the hardware.

My Windows taskbar has been vertical, running up the right side of my screen, for probably a decade.

One of several reasons that Opera was my web browser of choice for several years was its native support for a vertical tab bar. I could have dozens of tabs open, and be able to see all of them, and read their titles. It was tremendously useful, while it lasted.

PowerPoint has started putting context-sensitive tools and controls on the right side of the screen instead of just at the top, and the slide thumbnails on the left.

Chrome now makes the status bar at the bottom of the window invisible - freeing up an extra line of space in the window - unless it has something important to display (e.g. when you're hovering over a link and want to see the URL).

Reading/comparing/referring to two documents side-by-side is pretty darned useful in a number of different contexts. (Of course then each application window has to have a sensible layout for portrait-oriented display, as well....)

Yes, it's an added burden for developers to have to consider how their application might be used on displays with different aspect ratios. That doesn't mean that they shouldn't do so, and especially not that they should fail to consider how to present their product on the most common format today.

Comment Re:boats and planes (Score 2) 136

Boat and plane navigation is reasonably similar - it's 'head to waypoint', not 'navigate through twisty curves'.

Actually...the article points out that a major source of avoidable expense and delays is collisions that take place in narrow and congested waterways--and often with inanimate, stationary objects. Inadvertent groundings, collisions with moored vessels, difficulties in constricted canals and locks. Insurance is a big cost.

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