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I would have thought that to be true when viewing through the center of the galactic disk. But I would have thought that, when viewing towards the outer rim of the disk, infrared and microwaves would easily get through, even as most visible wavelengths would be appreciably attenuated by gas/dust and a lot fewer stars. edit And I guess I thought wrong. Although I do see mention of that effect in your link, Janus.

Since when do you need a source for an opinion ? Then why not ask what non-IGNORANT, enlightened people prefer ? And in what way do you mean 'better' ?

Almost anything painted matte black will heat up faster than if left with a shiny/colored surface. Black will absorb more of the incident radiation, while shiny or colored will reflect some. However, copper is also very conductive, which means heat will be carried away to all exterior surfaces quickly, and re-radiate. There is also the matter of the paint/copper interface, and how conductive it is. ( IIRC, copper needs a zinc based primer for paint adhesion, which further complicates matters ) So you asked a very vague question, to which no one can give an exact answer. I suggest redefining the parameters of your question, or simply trying the experiment with those you have in mind. Also keep in mind that the intended use comes into play; is it for heat storage, or removal ?

I Thought Islam had brought the old knowledge of the Greeks, and the scientific method of inquiry, back to Catholic Europe, to end the so called 'dark' ages, and usher in the Renaissance and the 'age of discovery'.

I did not personally know anybody who had tested positive until the beginning of October. The son ( in his middle 20s, and his girlfriend ), of a good friend of mine. His mother lives in the US, and he may have visited her. My friend, who had been in contact with his son, had to isolate from his second wife also, as she has an elderly, sick mother. We don't have many cases n the Niagara region of Ontario, but who knows how many asymptomatic people I may have come in contact with. Don't be a Trump; wear a mask, wash your hands, and, if possible, keep separated.

That would make for an interesting design exercise. The speed of sound in water is approx. 1500 m/s. Streamlining ( finesse ratio )would need to be extreme ( long and pointy ) so the shock wave would disturb a very thin cone of water. And Whitcomb area rule where any control surfaces are located. Propulsion would be another problem; the standard axial screw ( propeller ) could not be used as the thrust would need to be faster than supersonic ( no such thing as a supersonic propeller plane ). The only viable solution would be rocket propulsion. A 'trick' used by Russian torpedoes is to encase the hull n a sheath of gas ( usually Oxygen generated by H2O2 ) to enable faster speeds; that might also be applied. This however, would negate the benefit of the water as a heat sink to alleviate dynamic heating. Does anyone think anything of the sort would be feasible ?

Thank goodness Moon. I thought the age of Aquarius died with the coming of Disco in the middle 70s. So free love, and mind expanding drugs are still OK ? ( joking, I haden't even reached puberty yet in the early 70s )

I would like to see your paintings; paranormal research ( ghostbuster ? ), I can do without. The rest is gibberish, and playing with numbers. A 'model' is supposed to allow you to make predictions, and let you to check those predictions against observations. And while we don't have 'observations' of the tunneling effect producing Hawking Radiation, we base our best ( and accepted ) guesses on known Physics. ( entropy, thermodynamics and quantum mechanics ) Hence, known as 'educated' guesses; everything else is WAG.

So, what does this mean ? My electric drill no longer works ? People are 'delusional' when they argue against reality. ( not to worry, there's medication for that )

Well, for one, the Bible says "treat others as you would have them treat you". Isn't salvation in the afterlife ( heaven ) enough incentive ? No really, the realization that if everyone does it, everyone benefits ?

That's right. The Northrop F-20 Tigershark, a development of the F-5 and T-38, was involved in two crashes during development/sales tours, which were effectively caused by aggressive maneuvering ( sustained 9g ). This caused the pilots, Cornell and Barnes, to gradually lose peripheral vision until blackout; neither of themsurvived the crashes. Cornell died during a demonstration in Taiwan. Barnes died practicing an air show routine here in Canada. https://nationalinterest.org/blog/buzz/video-alert-watch-unfortunate-f-20-tigershark-first-prototype-crash-68937 https://www.latimes.com/archives/la-xpm-1985-05-15-mn-8541-story.html

No, but how you come to a stop might. ( falling off a building never killed anyone; it's that darned landing that does )

I would think if everyone treated everybody else, regardless of religion, a little more politely, quite a bit more progress would be made. Szczęść Boże

The fact that a re-entry vehicle is trying to slow down, and so presents a 'blunt' face to the atmosphere, is where most of the heating comes from. A 'streamlined' re-entry vehicle would hit the ground at thousands of miles per hour; the space shuttle re-enters bottom first to generate 'slow-down' drag, and the reason ablative tiles are attached to bottom surfaces.

Hope every American on this forum ( even ones who don't participate ) who hasn't already mailed in their vote, masks up ( along with any other PPE you can get your hands on ), and gets out to vote on Nov 3. Just ask yourself whose vision of America you would like to see as outlined in the debate; D Trump's 'everything for the economy', or J Biden's 'compassionate, fair, and respected worldwide' ? ( although even D Trump's 'vision' is a fabrication which he'll never deliver )

Stellar size BHs ( from collapsed former stars ) tend to follow orbits around the galaxy, just like stars do. We have an equivalent chance of colliding with another star as we do with a stellar BH. Galactic core sized ( millions or even billion solar mass ) BHs are another matter. Although just about every galaxy has one ( or more ), to be ejected and become 'rogue', they need to be involved in a collision. Just how many galactic collisions are there ( or were ) within 100 million light years ? Not very many at all. Chance of one reaching our galaxy within a billion years, virtually nil. Although in about 4.5 billion years Andromeda will collide with the Milky Way, chances of stellar or BH collisions are very low. ( interstellar pace is HUUUUGE compared to the size of stars )

The Sun is a magnitude 5.8 star, barely visible from 50 LY distance. However, about 100 years ago, we started broadcasting information embedded in EM carrier waves out into the universe. Any advanced civilization residing on one of the 133 star systems within 50 LY, would have detected us 50 years ago, and their armada, travelling here at light speed should be passing the outer gas giants as we speak. Yeah, I'm joking ( maybe ).

A good scientist doesn't believe anything, literally. However, even someone like Studiot will occasionally substitute 'have good evidence for' with 'believe". That's the human part.

I don't see how you get that from Studiot's comment. GR assigns a 'curvature to space-time at the exact location of the electron's mass/energy/momentum. But QM says the electron doesn't have an exact location. Now do you see the problem ?

Wait … Aren't we still in the Age of Aquarius ? Sex , drugs and Rock 'n Roll ? ( or is it just my weekend ) What does this mean ?

Not really. Science works the same for everyone. We deal with facts and observations, which are objective; not opinion, which is subjective.

Both sounded more Presidential tonight. Biden seemed more unflustered and coherent. Trump interrupted much less. The fact that Trump presented disinformation as facts isn't realized by most of his supporters. When 3000 people were killed in the WTC attacks, America waged several wars on terror, at a cost to the economy of billions of dollars per year. Yet Trump is obsessed with not doing any harm to the economy ( and its recovery ) even though 220 000 people have died from Covid-19. So far !

Why is everyone always picking on cats ? Really. My cats want to know. Or is this a comment on the membership, and the quality of discussion here ?

It's kind of like you don't realize there is no paradox, and further, it has nothing to do with length contraction in inertial frames. No, YOU haven't. Your attitude and 'far removed from science' ideas have. None of us like talking to a brick wall; take other's comments under consideration, instead of jumping topics all over the place.

No. What he is attempting to explain, at that point, is that anything with mass-energy ( and momentum ) curves space-time, just like the curved grid lines around a ball with mass in the 2 dimensional representation. Since the electron has very little mass-energy, the curvature is very small and localized, but the electron has a probabilistic nature and cannot be localized. The curvature, then, has to be probabilistic also. IOW, just as the electron has varying probabilities of being in different places, so should its gravity, or space-time curvature. GR, however is a classical deterministic theory. The space-time curvature is where the event ( electron ) is in space-time. QM and GR are based on differing paradigms, and GR, as it stands, cannot handle the indeterminateness of the electron's state ( or position, momentum, energy, or even time ) prior to wave function collapse. Google SuperString theory or Loop Quantum Gravity.