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Comment Air India's "Perfect" Flight Record. (Score 1) 108

Hi. I think you are confused.

Air India crashes/fatalities:
* Air India Flight 101 CONTROLLED FLIGHT INTO TERRAIN -- https://en.wikipedia.org/wiki/...
* Air India Flight 855 PILOT ERROR -- https://en.wikipedia.org/wiki/...

What does the word perfect mean to you? Those are crashes. People died.

We can even add:
* Air India Flight 182 BOMBING -- https://en.wikipedia.org/wiki/...

Though that's also on the staff at the airport doing security screenings.

Comment Re:We're headed for Venus, but still we stand stro (Score 1) 66

To be extra clear, here: titanium melts around 1,900 kelvin. The temperature of re-entry is 3,200 kelvin. Yes, 3,200 kelvin is "below" the temperature required to make titanium boil (by 300 kelvin), but you'll note that the 1,900 is 3,200 by 1,300.

Who honestly thinks titanium that's been heated to 'just below' its boiling point for half an hour, will be somehow intact once it's slow enough to not self-generate plasma due to atmospheric drag?

Ridiculous.

Comment Re:We're headed for Venus, but still we stand stro (Score 1) 66

How does a thing that isn't water, 'water in the ocean'? What? A thing can't water. The only thing that is water, is H2O.

Also, no -- it will not survive atmospheric re-entry. The atmosphere see to that. The heat of re-entry exceeds the temperature of Venus by *THOUSANDS OF DEGREES*.... It will not survive in 1 piece. This isn't a matter of atmospheric pressure, nor is this a matter of G-shock. It's plasma; it'll be in an envelope of super-heated plasma. Why do you think they can't use the radios on the Shuttle during re-entry? High energy plasma -- at THOUSANDS OF DEGREES.... Sheesh.

Comment It won't survive re-entry. (Score 1) 66

'"As this is a lander that was designed to survive passage through the Venus atmosphere, it is possible that it will survive reentry through the Earth atmosphere intact, and impact intact," Langbroek wrote in a blog update"'

Uh, no.

1) High-energy plasma at 3,200 K upon re-entry. This occurs for 25 minutes or so. This is why Columbia became ... a large number of pieces of wreckage strewn across multiple US states.
2) Venera probes use drag-parachutes to reduce velocity to the point that they can survive entry into the atmosphere of Venus. But, this was built by the Soviet union -- it didn't get out of low Earth orbit. Do you think that parachute functions? It doesn't, it won't.
3) The reasons cited for it 'surviving' re-entry are ... G-forces and atmospheric pressure. None of those address the fact that, though the surface of Venus is ~= 737K ( https://en.wikipedia.org/wiki/... ), you'll notice that the surface temperature of Venus is 2,463 kelvin 'colder' than atmospheric re-entry. What material do you think the probe is made of? Unobtanium?

Ridiculous. It will not survive atmospheric re-entry. it will not be 'a single piece' when it (or most of it, the parts that weren't vaporized by high-energy plasma), gets to sea-level.

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.

Comment AI is a boondoggle (Score 1) 35

AI breaks everything it touches. It is a shame executives in the government and private sector are so blown away by buzzwords. The word "cloud" is still wowing them like it was magic. Everything that is hosted in the cloud is slower and less reliable than when it was locally hosted by a wide margin. Once everything we search for at work is junked up with AI slop, all work will slow to a crawl, but executives who don't understand technology will blame the people. AI is just the latest boondoggle that billions will be wasted on. It is a mistake.

Comment Terrible idea (Score 1) 47

by uncoveror (#65235751) Attached to: NAB Calls For End of ATSC 1.0
Like all ideas driven purely by corporate greed, this is a terrible idea. Netxgen TV is hard to pick up. My Sony TV has a tuner for it, but half of the antennas I have tried either don't get it at all, or drop the picture frequently. I frequently give up on it and just watch the ATSC 1.0 channels instead. Another problem is that several manufacturers have dropped Nextgen tuners because of licensing fees. No one wants a separate tuner box. We want to use our TV for TV. Use of Nextgen needs to remain optional.

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