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Comment Re:technical project management reply to module ow (Score 1) 286

*types in password case insensitve a few times...

***The password you have entered is incorrect. Your account has been locked.***

See? Case sensitivity matters. And I _do_ see mynotes or MyNotes as 2 different things, and most people I know do too (as they should).

Example: Windows explorer kindly hides the file extension by default. The MyNotes (or mynotes) can be the executable and have a mynotes.ini on top of you having a mynotes.txt file.

Comment Re:I recently replaced (Score 1) 132

If you go to a Ford dealer, the salesman isn't going to recommend a Porsche. If you go to Taco Bell, they're not going to recommend Wendy's.

Lots of folks have experience installing gas furnaces. That's what they know. They don't know heat pumps. They could learn, but learning is hard. If they can keep selling gas furnaces, that's easier.

Comment Re:We need solutions that work in the UK. (Score 3, Informative) 132

My home is made with cement blocks - just like most houses in the UK. It's a massive thermal mass.

I installed heat recovery ventilation which also helps hold heat in while maintaining a constant supply of fresh air.

Which means that temperature swings outside don't really affect me.

Comment Re:The neighbours being disappointing again (Score 4, Informative) 132

I've been using it for five years now. I'm aware how much electricity costs. But for me, it's discounted by 33% due to solar PV. And my heat pump is 150-300% efficient.

When it makes sense to replace the roof on my house I can double my solar capacity and I'll increase my electricity storage capacity.

So long term it will cost me way less. And, as I noted, the benefits go beyond cost. It's quieter, it's not spewing fumes outside my house, my home has less fire risk, etc.

Comment The neighbours being disappointing again (Score 5, Insightful) 132

I installed a heat pump back in 2021. It's fantastic in an Irish or British climate. Home's much warmer and much quieter. Don't need to have CO monitors in my house, don't need to remember to schedule oil deliveries, and so many more things. I can stand outside my back door and not get assaulted by fumes.

All the energy I use at this point is electric - heating, cooking, transportation, all of it. And I offset 33% of the electricity I use via solar PV. When I need to replace my roof, I'll put panels on my house and double my solar production.

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.

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