Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!

 



Forgot your password?
typodupeerror

Comment Re: Simple... (Score 1) 199

"Weather alerts, flood, tornado, etc. should be able to wake people up."

They're already *able* to wake people up. What do you do about people not wanting to be woken up who silence their phones? Do you pass legislation making it illegal for phones to be able to silence certain alerts? Okay, some people will put their phones somewhere other than their bedside so they can't be woken up. Do you make that illegal, or at some point do you just say "Okay, you know what, this is on you"?

Comment Re: Simple... (Score 1) 199

Okay, all those alerts saved one life.

And all those alerts convinced a bunch of people to silence their alerts, and resulted in lives lost.

Have you bothered to compare the two numbers to see whether the alerts are, in fact, justified? Or do you always only look at a benefit and ignore any associated costs?

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:I'm skeptic (Score 2) 62

No, 1 nanometer is orders of magnitude too high an estimate. Observed data constrains primordial black hole masses to about 10^13kg, which gives a Rsch of about .0001 nanometers. That's only a couple of orders larger than a proton, it is *not* easy to feed them and one is not going to fall into a star and completely eat it. In the unlikely event it collides with a star, it will absorb scarcely any of it as it passes through.

Comment Re: Excellent! (Score 1) 167

"It's not about "hating" Jews, it's about hating Israeli genocidal policies,"

Weird how so much hate about Israeli genocidal policies gets directed against non-Israeli Jews in the US.

"At this point, Jews are doing to others that which was done to them."

Wait, I thought it was Israeli genocidal policies. Now one paragraph later you're talking about how it's Jews doing it.

Submission + - Elon Musk's daily $1 million payouts at Trump rally draw legal scrutiny 3

echo123 writes: HARRISBURG, Pennsylvania, Oct 20 (Reuters) — Billionaire Elon Musk promised on Saturday to give away $1 million each day until November's election to someone who signs his online petition, with the first prize awarded at a PAC event supporting Republican Donald Trump, raising questions about the legality of the payments.

Musk gave a $1 million check to an attendee of his America PAC event in Harrisburg, Pennsylvania, aimed at rallying supporters behind presidential candidate Trump. The winner was a man named John Dreher, according to event staff.

"By the way, John had no idea. So anyway, you're welcome," the Tesla founder said as he handed Dreher the check.

Comment Re:Brazil has Free Speech (Score 1) 87

"That is similar as pointing a knife or a gun"

It is absolutely not similar to pointing a knife or a gun.

Words are words. They are not knives or guns. Your argument is, again, the argument of every would-be censor of ideas in the world.

Lick the boot harder, bootlicker.

Slashdot Top Deals

How can you do 'New Math' problems with an 'Old Math' mind? -- Charles Schulz

Working...