For Questions That Don't Merit Their Own Thread

[kerbiloid]

Ok, correction.

Cats & dogs could not develop a civilisation without a remotely controlled intermediate semi-autonomous agent, because they sleep 20/24.

They need another species to ride it.

Edited June 23, 2020 by kerbiloid

[p1t1o]

You think that the cats havent already created a superior civilisation? Think about how the lives of most house cats are. 

They *do* have remotely controlled semi-autonomous intermediates - us. They have trained us to *want* to do everything for them, feel genuine achievement when we do so and we think its all our idea. Even right now some of you are thinking "Yeah except MY cat". You have been well trained and your line will produce many high quality caretakers - and you probably will train your offspring to like and take care of cats.

"lol! Cats dont have industry!" - No? What keeps a housecat warm? Electricity and power stations - and they didnt even have to build them or run them. And what, exactly, is a catfood factory, if it isnt technology with the sole purpose of providing cats with free food for life? "Our" industry? There are people whose entire careers revolve around creating instruments which make it easier for humans to open catfood containers.

"But we put animals in zoos!" - uh-huh, ever seen a housecat in a zoo? Isnt that idea unthinkable?

"Ok, but we could easily conquer them." - ok, go ahead, contemplate hurting a cat, strong mental block there isnt there? If there is a person without the mental block on hurting cats, we label them "sociopaths" or "sadists" and ostracise them from community, or else isolate them in healthcare (keeps them away from cats)

And I write all this still with the genuine desire to one day provide a comfortable home to a nice cat, without any thought of reward. Its uncontrollable and I sincerely have no idea where it comes from other than "Cats are so cute and fluffy and if one came over for a snuggle without me prompting it, I would just melt from joy."

I want to write something more about civilisations and our place in them but really all I can think about now is how cute cats are.

[kerbiloid]

2 hours ago, p1t1o said:

They *do* have remotely controlled semi-autonomous intermediates - us.

That's exactly what I said. But also this means that they needed an intermediate species to build it.

Without trained apes the cats would be still planning 20/24.

***

Also you could add the spacenautics. There are man-rated vessels, but still no cat-rated, as they don't agree to live in zero-G.

Edited June 23, 2020 by kerbiloid

[Nightside]

5 hours ago, kerbiloid said:

Also you could add the spacenautics. There are man-rated vessels, but still no cat-rated, as they don't agree to live in zero-G.

This theory also explains Laika’s fate. 

[kerbiloid]

19 minutes ago, Nightside said:

This theory also explains Laika’s fate. 

The humanity has started the Space Age by killing a (she-dog) with ICBM.

[p1t1o]

18 hours ago, kerbiloid said:

The humanity has started the Space Age by killing a (she-dog) with ICBM.

Well since she came back from her first trip hyperintelligent and completely impervious to human weapons, it was our only option.

I mean, they dont teach that part, but its clear to me from context alone.

[kerbiloid]

But she didn't come back. She was sitting inside that ICBM.

[Terwin]

On 6/22/2020 at 12:39 PM, EchoLima said:

Are there distinct "direct" and "relay" antennas IRL, or does that only exist in KSP?

In real life you have send only(radio station), receive only(radio, pager, GPS), and send-recieve(cell phone).

I suppose you could have antennas that are or are not compatible with the Deep Space Network, but there is no real reason they could not use the same antennas for the different types.

I always just imagined that the difference in KSP antennas was primarily in the processing/amplification hardware and the power supply, with the antennas only visually different so people would not confuse them in images.

[JoeSchmuckatelli]

I thought the EM drive was debunked.  This article makes it sound like there is still room for debate? 

https://www.google.com/amp/s/www.wired.com/story/nasas-emdrive-leader-has-a-new-interstellar-project/amp

[Nightside]

5 minutes ago, JoeSchmuckatelli said:

I thought the EM drive was debunked.  This article makes it sound like there is still room for debate? 

https://www.google.com/amp/s/www.wired.com/story/nasas-emdrive-leader-has-a-new-interstellar-project/amp

As I recall, the measured thrust of the EmDrive was due to a flexing power cable.

Maybe they are working on building an extension cord to space.

[K^2]

1 hour ago, JoeSchmuckatelli said:

I thought the EM drive was debunked.

The biggest problem with the fundamental concept of EM Drive is that the initially proposed explanation for why it was expected to work comes entirely from classical electrodynamics. And classical electrodynamics is built on Minkowski metric, which has certain space-time symmetries, which by Noether's Theorem lead to momentum being a conserved current, meaning you can't have a reactionless drive, and conservation of energy, which means that unless you're expending reaction mass, you at best have a photon drive which is horribly inefficient way to move about. So it's mathematically impossible for electromagnetic drive to operate as advertised. Either it doesn't work at all, or the reason it works has nothing to do with electrodynamics. And if it's the later, and we stumbled on something that produces thrust by a novel, unknown before method, entirely by chance, in which case, everything they've been trying to do to study it is kind of hopeless.

Of course, it was extremely unlikely that it was ever a real effect at all. Noether's Theorem is actually a bit more general than just electrodynamics. It's kind of in foundation of all modern particle physics and cosmology. An entirely underrated theorem by an inexcusably underrated mathematician, Emmy Noether. The odds of us stumbling on symmetry violation or new force that exists outside of known symmetries by pure chance with something like EM Drive is astronomically low. Primarily, because we've spent a lot of effort intentionally setting up experiments to look for these things. So it being something trivial and unaccounted for was almost a given. I haven't actually heard any specifics since the craze in the news died down, but what @Nightside said about power cable sounds very plausible.

Don't get me wrong. It's good that there are people out there who say, "Well, fine, but why did we keep measuring thrust?" and keep looking into it until they find satisfactory answer. It's good practice for when we go on to test things we're actually have doubts about, if nothing else, and sometimes, you discover a tangential effect that's of worth. But from perspective of whether EM Drive was a real deal, there was no reason to wait for a debunking. Despite how awesome of a discovery that would be, I'd be comfortable enough not even trying it, because that's how bad the odds of it being a real effect were.

[SOXBLOX]

Yes, they were measuring torque produced by magnetic fields from the power cable. Experimenters didn't have enough shielding for the job, so they skimped.

As K^2 says above, the odds of it being due to new physics are extraordinarily low. It would violate conservation of momentum, so we'd have to rework physics. Not likely.

Edited June 27, 2020 by SOXBLOX

[JoeSchmuckatelli]

3 hours ago, K^2 said:

The biggest problem with the fundamental concept of EM Drive is that the initially proposed explanation for why it was expected to work comes entirely from classical electrodynamics. And classical electrodynamics is built on Minkowski metric, which has certain space-time symmetries, which by Noether's Theorem lead to momentum being a conserved current, meaning you can't have a reactionless drive, and conservation of energy, which means that unless you're expending reaction mass, you at best have a photon drive which is horribly inefficient way to move about. So it's mathematically impossible for electromagnetic drive to operate as advertised. Either it doesn't work at all, or the reason it works has nothing to do with electrodynamics. And if it's the later, and we stumbled on something that produces thrust by a novel, unknown before method, entirely by chance, in which case, everything they've been trying to do to study it is kind of hopeless.

Of course, it was extremely unlikely that it was ever a real effect at all. Noether's Theorem is actually a bit more general than just electrodynamics. It's kind of in foundation of all modern particle physics and cosmology. An entirely underrated theorem by an inexcusably underrated mathematician, Emmy Noether. The odds of us stumbling on symmetry violation or new force that exists outside of known symmetries by pure chance with something like EM Drive is astronomically low. Primarily, because we've spent a lot of effort intentionally setting up experiments to look for these things. So it being something trivial and unaccounted for was almost a given. I haven't actually heard any specifics since the craze in the news died down, but what @Nightside said about power cable sounds very plausible.

Don't get me wrong. It's good that there are people out there who say, "Well, fine, but why did we keep measuring thrust?" and keep looking into it until they find satisfactory answer. It's good practice for when we go on to test things we're actually have doubts about, if nothing else, and sometimes, you discover a tangential effect that's of worth. But from perspective of whether EM Drive was a real deal, there was no reason to wait for a debunking. Despite how awesome of a discovery that would be, I'd be comfortable enough not even trying it, because that's how bad the odds of it being a real effect were.

You are totally someone who I would want to sit down with over a beer and pick your brain! 

 

Thanks for the answer - and doubly thanks for the link to Ms Noether! 

 

Now for a bigger question - the guy referred to in the article doesn't seem like a complete quack... What about some of the other, wildly experimental stuff they describe? 

Edited June 27, 2020 by JoeSchmuckatelli

[K^2]

15 minutes ago, JoeSchmuckatelli said:

Now for a bigger question - the guy referred to in the article doesn't seem like a complete quack... What about some of the other, wildly experimental stuff they describe? 

Some of the proposals that Harold White and his team have looked into have at least some scientific basis, even if all are kind of out there. But there's also stuff like EM Drive, which I'm pretty sure only showed up on their radar because several other teams reported results on, and they had equipment to look into it. I think the article might have just talked about EM Drive because it made a bit of a buzz a while ago, but the actual interest is in things like quantum thrusters.

To be clear, all of these ideas are highly speculative. The difference is that idea for EM Drive is based on a self-contradiction, so it could have only worked by complete dumb luck. Other suggestions are based on hypotheses of how vacuum works that are entirely ad-hoc at this point and aren't supported by any experiments, but that's how pretty much every theory starts out. Most of them end up being wrong, but you find out by testing.

I do think the team kind of over-sell what they're really doing, but I guess that's how you get funding.

[magnemoe]

17 hours ago, K^2 said:

The biggest problem with the fundamental concept of EM Drive is that the initially proposed explanation for why it was expected to work comes entirely from classical electrodynamics. And classical electrodynamics is built on Minkowski metric, which has certain space-time symmetries, which by Noether's Theorem lead to momentum being a conserved current, meaning you can't have a reactionless drive, and conservation of energy, which means that unless you're expending reaction mass, you at best have a photon drive which is horribly inefficient way to move about. So it's mathematically impossible for electromagnetic drive to operate as advertised. Either it doesn't work at all, or the reason it works has nothing to do with electrodynamics. And if it's the later, and we stumbled on something that produces thrust by a novel, unknown before method, entirely by chance, in which case, everything they've been trying to do to study it is kind of hopeless.

Of course, it was extremely unlikely that it was ever a real effect at all. Noether's Theorem is actually a bit more general than just electrodynamics. It's kind of in foundation of all modern particle physics and cosmology. An entirely underrated theorem by an inexcusably underrated mathematician, Emmy Noether. The odds of us stumbling on symmetry violation or new force that exists outside of known symmetries by pure chance with something like EM Drive is astronomically low. Primarily, because we've spent a lot of effort intentionally setting up experiments to look for these things. So it being something trivial and unaccounted for was almost a given. I haven't actually heard any specifics since the craze in the news died down, but what @Nightside said about power cable sounds very plausible.

Don't get me wrong. It's good that there are people out there who say, "Well, fine, but why did we keep measuring thrust?" and keep looking into it until they find satisfactory answer. It's good practice for when we go on to test things we're actually have doubts about, if nothing else, and sometimes, you discover a tangential effect that's of worth. But from perspective of whether EM Drive was a real deal, there was no reason to wait for a debunking. Despite how awesome of a discovery that would be, I'd be comfortable enough not even trying it, because that's how bad the odds of it being a real effect were.

Yes, the reason why looking into the EM-drive was that even if it was very very low odds if it worked it would change spaceflight forever. 
No not much impact on manned flights in the short term but probes and even satellites would benefit a lot. 

[ARS]

Is it true that human body will melt (corroded away, chipped bit by bit) when exposed to heavy nuclear radiation? Like when you're exposed into the open core of nuclear reactor, with the radiation level steadily rising, assuming you aren't killed by intense heat first, does the increasing radiation level in your body caused it to eventually melt? 

[kerbiloid]

>100 Sv (>10 000 rem) at once means "death under ray" due to cerebral haemorraghes.

Loss of consciousness in 1..2 minutes.

[magnemoe]

2 hours ago, kerbiloid said:

>100 Sv (>10 000 rem) at once means "death under ray" due to cerebral haemorraghes.

Loss of consciousness in 1..2 minutes.

Extreme radioactive event like standing on top of the Chernobyl reactor is likely to create other stuff like steam explosions who would kill you  before the radiation does. Don't think anybody has died within seconds of radiation. 
Outside of  people just below the nuclear bombs but that was thermal shock more than radiation. If hit by an gigawatt laser you don't care if its IR or x-ray. 
 

[kerbiloid]

11 minutes ago, magnemoe said:

Extreme radioactive event like standing on top of the Chernobyl reactor is likely to create other stuff like steam explosions who would kill you  before the radiation does. Don't think anybody has died within seconds of radiation. 

3 hours ago, ARS said:

assuming you aren't killed by intense heat first,

 

[DDE]

14 hours ago, ARS said:

Is it true that human body will melt (corroded away, chipped bit by bit) when exposed to heavy nuclear radiation? Like when you're exposed into the open core of nuclear reactor, with the radiation level steadily rising, assuming you aren't killed by intense heat first, does the increasing radiation level in your body caused it to eventually melt? 

This is unknown.

13 hours ago, kerbiloid said:

>100 Sv (>10 000 rem) at once means "death under ray" due to cerebral haemorraghes.

Loss of consciousness in 1..2 minutes.

Yes and no. I did at one point look into it, and effects on the nervous system are less "reliable than some would have you believe. The brain is actually a rather resilient organ.

The absolute record I know of is Robert Peabody, who lived for about 49 hours after taking about 100 Sv. He did complain of burning (and not much else), but he was functional enough to flee the building - whereas people involved in lesser incidents have often had their brains too scrambled to even walk away from the incident site.

Most of the cases of extreme radiation exposure are 'criticality incidents' - a reactor happening where it's not supposed to, sometimes literally in someone's hands.

https://www.iaea.org/publications/6111/the-criticality-accident-in-sarov

Of these, the Nenyoksa incident last summer is the most recent one.

Bottom line is, the biological effects of Acute Radiation Syndrome (pun intended) are fatal and immediate or near-immediate at far lesser dosages, whereas thermal effects are insignificant.

[kerbiloid]

15 minutes ago, DDE said:

Robert Peabody, who lived for about 49 hours after taking about 100 Sv.

Quote

Calculations based on analysis of his gold wedding ring and on tissue samples showed that he had received more than 700 rems of radiation,

14 hours ago, kerbiloid said:

>100 Sv (>10 000 rem) at once means "death under ray" due to cerebral haemorraghes.

Loss of consciousness in 1..2 minutes.

Edited June 30, 2020 by kerbiloid

[DDE]

How long until a Moldovan Space Program?

https://www.defenseworld.net/news/27318/Fake_Russian_Ka_26_Helicopter_Factory_Unearthed_in_Moldova#.XvyFuGlRXqs

[kerbiloid]

16 minutes ago, DDE said:

How long until a Moldovan Space Program?

https://www.defenseworld.net/news/27318/Fake_Russian_Ka_26_Helicopter_Factory_Unearthed_in_Moldova#.XvyFuGlRXqs

You pay, they make.

[magnemoe]

3 hours ago, DDE said:

How long until a Moldovan Space Program?

https://www.defenseworld.net/news/27318/Fake_Russian_Ka_26_Helicopter_Factory_Unearthed_in_Moldova#.XvyFuGlRXqs

Now that is weird. Why not fake something simpler like cars. Plenty of fake supercars around. 
Helicopters as they pointed out are very regulated. 

However fake aircraft parts is an problem but mostly for the private plane marked. Aircraft parts tend to be expensive even for off the shelf parts like bolts because the paperwork even if the bolt itself is very standard and widely used. 

SpaceX had an run in with bad parts, as in the struts holding the helium tanks inside the LOX tank on one Falcon 9 doing an delivery run to ISS. 
This was not an fake part but an subcontractor delivering an substandard part if I remeber correctly. 
 

Edited July 1, 2020 by magnemoe

[K^2]

1 hour ago, magnemoe said:

Now that is weird. Why not fake something simpler like cars. Plenty of fake supercars around. 
Helicopters as they pointed out are very regulated.

If you didn't see Transnistria (aka Transdniestria, Prednistrovie) mentioned and went, "Oh yeah, that makes sense now," you probably should read up on the region a bit. The famous Mythbusters quote, "I reject your reality and substitute my own," can be a state moto. It won't surprise me one bit if it turns out that these helicopters were fully certified in Transnistria.