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Posted
4 hours ago, swansont said:

The ISS is for astronauts who live a pretty spartan existence, and have things delivered to them, something that wouldn’t happen with a remote habitat

Why not? There are plenty of 'things' that can be made and handled outside of a shielded space. Especially using robotics, or remotely operated machinery. 

 

4 hours ago, swansont said:

The heat from that surface would also go inward. 

If there's a net loss of heat, it's doing a job. 

------------------------------  

On the question of detecting aliens from a heat signal, maybe the aliens would not want to be detected. If you are dumping heat via radiators, wouldn't it be possible to focus the radiated heat like a lazer, on infinity, so that you could only detect it if you happened to cross a tiny channel through space? And then you would just get an intense signal for a few fractions of a second, as you crossed the beam. 

So the odds of detecting aliens might be tiny, because that's the way they want it. 

Posted
1 hour ago, mistermack said:

Why not? There are plenty of 'things' that can be made and handled outside of a shielded space. Especially using robotics, or remotely operated machinery. 

The ISS doesn’t have to produce their own food, fabricate equipment, or have a hospital, to name three off the top of my head.

 

1 hour ago, mistermack said:

If there's a net loss of heat, it's doing a job. 

At best it’sZ inefficient to add the extra heat to your heat removal system.

 

1 hour ago, mistermack said:

------------------------------  

On the question of detecting aliens from a heat signal, maybe the aliens would not want to be detected. If you are dumping heat via radiators, wouldn't it be possible to focus the radiated heat like a lazer, on infinity, so that you could only detect it if you happened to cross a tiny channel through space? And then you would just get an intense signal for a few fractions of a second, as you crossed the beam. 

You could shape things to emit a little more in a particular direction, but this would beva small effect. Nothing like a laser.

Posted
13 hours ago, swansont said:

But the scale in still quite small. 10m or so for the craft. 24 tons (3 tons each x8) for that size is a lot.

That is true, but it indicates that a magnetic field can be used in ways that allow for a better coverage from several small magnets rather than one huge one. I think the devil will be in the engineering with this one. Even planetary size mag fields have been proposed. 

Posted
43 minutes ago, Moontanman said:

That is true, but it indicates that a magnetic field can be used in ways that allow for a better coverage from several small magnets rather than one huge one. I think the devil will be in the engineering with this one. Even planetary size mag fields have been proposed. 

How much power would be required for a planetary-size field?

Posted
35 minutes ago, swansont said:

How much power would be required for a planetary-size field?

I'm going to display my physics ignorance here. 

Does a field require power? If no work is being done, is the power requirement just needed because of inefficiencies in the system? 

A bar magnet produces a field, but where is the power input? If the field isn't doing any work, the magnet doesn't need an energy input. 

Does that translate to electromagnets? With superconductors, you can have very low resistance, so you can have a huge flow of current with very little expended energy. So progress in the field of superconductivity means the prospect of bigger stronger fields, with smaller and smaller energy losses, as technology advances. And of course, space is very cold, so it favours superconductivity. 

That's how I see it at the moment, but I'm happy to be put right on the subject. 

Posted
14 minutes ago, mistermack said:

I'm going to display my physics ignorance here. 

Does a field require power? If no work is being done, is the power requirement just needed because of inefficiencies in the system? 

Depends on how it’s generated. Permanent magnets don’t but e.g. a current loop continuously does; there is dissipation - in that case resistive losses, or in maintaining the low temperatures of a superconductor.

There are also radiative losses.

Even permanent magnets would require energy to assemble a configuration and to maintain the physical structure.

14 minutes ago, mistermack said:

A bar magnet produces a field, but where is the power input? If the field isn't doing any work, the magnet doesn't need an energy input. 

Does that translate to electromagnets? With superconductors, you can have very low resistance, so you can have a huge flow of current with very little expended energy. So progress in the field of superconductivity means the prospect of bigger stronger fields, with smaller and smaller energy losses, as technology advances. And of course, space is very cold, so it favours superconductivity. 

Sunlight, however, is warm. Out at Mars, the solar levels are almost 600W/m^2

 

Posted
2 minutes ago, swansont said:

Sunlight, however, is warm. Out at Mars, the solar levels are almost 600W/m^2

Yes, but not in the shade. You can reflect solar energy away for virtually no energy input. 

Posted
1 hour ago, mistermack said:

Yes, but not in the shade. You can reflect solar energy away for virtually no energy input. 

Some of the energy. But the mirrors will heat up, and radiate into the shaded are.

Posted
11 minutes ago, swansont said:

Some of the energy. But the mirrors will heat up, and radiate into the shaded are.

In space, shading can be pretty efficient. If the mirror is one metre from the shaded equipment, then re-radiating might be significant. But if the mirror is 100 metres away, then very little will hit. And one kilometre away, it's going to be negligible. So you can easily site the mirror so that it's not a problem. 

Posted
2 hours ago, mistermack said:

In space, shading can be pretty efficient. If the mirror is one metre from the shaded equipment, then re-radiating might be significant. But if the mirror is 100 metres away, then very little will hit. And one kilometre away, it's going to be negligible. So you can easily site the mirror so that it's not a problem. 

You invite other problems, since the orbital speeds will not be the same. Plus you need a bigger mirror, and there will be diffraction - light will get around the mirror.

Posted (edited)

These problems are being met with today's tech, and were met with yesterday's tech too.

One example of how efficient shading is in space is the Parker Solar Probe by NASA. 

The probe and all of it's equipment is designed to approach to within about four solar diameters of the surface of the Sun, and yet it's equipment is just shaded by a 4.5 inch thick carbon composite shield. 

At the other end of the temperature scale are the infra-red space telescopes. The Spitzer mission ran for about 20 years, and ended about 3 years ago.    https://en.wikipedia.org/wiki/Spitzer_Space_Telescope 

It needed very low temperatures to operate. It ran it two stages, the cold and hot missions. In the cold mission the mirror got extra cooling from liquid helium, as well as protection by the sun shield. It operated at about 5.5 K.

When the liquid helium ran out, they ran a 'warm' mission, just protected by the shield and operating at 28.7 K unaided. This allowed an 11 year extension of the mission, on restricted wavelengths at a constant 28.7K

So shielding does work, it makes very low temperatures achievable, and of course, the tech moves on and improves all the time. High temperature superconductors can now operate above 90 K so the achievable temperatures in the shade in space won't need any extra cooling.

Wikipedia says about superconductors "  a superconductor has a characteristic critical temperature below which the resistance drops abruptly to zero.[1] [2] An electric current through a loop of superconducting wire can persist indefinitely with no power source.[3][4][5][6]"

So at least in theory, you can maintain a magnetic field without any input power. In practice it will probably not be that easy, but it will be interesting how the technology progresses. 

Edited by mistermack
Posted
1 hour ago, mistermack said:

These problems are being met with today's tech, and were met with yesterday's tech too.

One example of how efficient shading is in space is the Parker Solar Probe by NASA. 

The probe and all of it's equipment is designed to approach to within about four solar diameters of the surface of the Sun, and yet it's equipment is just shaded by a 4.5 inch thick carbon composite shield. 

which gets it to 30 C.

1 hour ago, mistermack said:

At the other end of the temperature scale are the infra-red space telescopes. The Spitzer mission ran for about 20 years, and ended about 3 years ago.    https://en.wikipedia.org/wiki/Spitzer_Space_Telescope 

It needed very low temperatures to operate. It ran it two stages, the cold and hot missions. In the cold mission the mirror got extra cooling from liquid helium, as well as protection by the sun shield. It operated at about 5.5 K.

When the liquid helium ran out, they ran a 'warm' mission, just protected by the shield and operating at 28.7 K unaided. This allowed an 11 year extension of the mission, on restricted wavelengths at a constant 28.7K

 

Did you read the part about how Spitzer was placed in an orbit far from earth, owing to the heat load it would have from being nearby? That’s how they got the low temperature, which would not be the case for this magnetic field generator.

You don’t have much area that faces only deep space, which is how they got the small sensor to be cool

 

Posted (edited)
8 hours ago, swansont said:

Did you read the part about how Spitzer was placed in an orbit far from earth, owing to the heat load it would have from being nearby? That’s how they got the low temperature, which would not be the case for this magnetic field generator.

Which generator? I was assuming that the real need for active shielding would be on more distant travel, not near Earth. Close to Earth there is natural shielding from the Earth's magnetic field. When you mentioned the power of the Sun at Mars, I assumed that you were addressing distant journeys. 

However, the James Webb is stationed much closer to Earth, but it's shield still produces very low temperatures :   

image.png

The sunshield is the size of a tennis court, which shows that you can shield more than just a tiny receptor. 

"The sunshield acts as large parasol allowing the main mirror, optics, and instruments to passively cool to 40 kelvins (−233 °C; −388 °F) or cooler,[6] and is one of the enabling technologies that will allow the JWST to operate.[10] The kite-shaped sunshield is about 21 by 14 metres (69 by 46 ft) in size,[11] big enough to shade the main mirror and secondary mirror, leaving only one instrument, the MIRI (Mid-Infrared Instrument), in need of extra cooling.[6] The sunshield acts as a V-groove radiator and causes a temperature drop of 318 K (318 °C, 604 °F)[12] from front to back.[11] In operation the shield will receive about 200 kilowatts of solar radiation, but only pass 23 milliwatts to the other side.[13][11]

The sunshield has it's own wiki page :  https://en.wikipedia.org/wiki/James_Webb_Space_Telescope_sunshield  

 

Edited by mistermack
Posted
15 hours ago, mistermack said:

Which generator? I was assuming that the real need for active shielding would be on more distant travel, not near Earth.

The context was a magnetic field on Mars.

Moontanman’s linked paper that initiated this tangent (and that nobody else apparently read) was “How to create an artificial magnetosphere for Mars”

15 hours ago, mistermack said:

However, the James Webb is stationed much closer to Earth

1.5 million km away.

That would mean a superconducting wire loop more than 9 km in circumference

Posted
1 hour ago, swansont said:

The context was a magnetic field on Mars.

Moontanman’s linked paper that initiated this tangent (and that nobody else apparently read) was “How to create an artificial magnetosphere for Mars”

Well, I don't waste much time on such distant speculative articles, the title was more than enough for me. 

I'm posting about creating a shield for a space craft or station, and even that is speculative, but at least it's forseeable as possibly practical, given time. 

1 hour ago, swansont said:

That would mean a superconducting wire loop more than 9 km in circumference

To do what?

Posted
6 minutes ago, mistermack said:

I'm posting about creating a shield for a space craft or station, and even that is speculative, but at least it's forseeable as possibly practical, given time.

Then don’t object/respond to what I’m posting, because I’m not. 

6 minutes ago, mistermack said:

To do what?

To make a current loop, if it’s going to be 1.5 million km from the planet.

Posted
5 minutes ago, swansont said:

Then don’t object/respond to what I’m posting, because I’m not.

Fair enough. Your posting seems deliberately short and cryptic, so I won't post to it, unless the meaning is clear. 

7 minutes ago, swansont said:

To make a current loop, if it’s going to be 1.5 million km from the planet.

Like that for example. 

Posted
1 minute ago, mistermack said:

Like that for example. 

I assumed you posted understanding the context of the discussion, rather than just naysaying what I said. I apologize for overestimating your effort at due diligence.

Posted

Is there any chance we can discuss this report from Minot air base? This is not a video and The paper lists the many ways the sighting was documented and is very interesting to say the least. I am thinking of you @swansonT, your input would be greatly appreciated. 

Posted (edited)
16 hours ago, Moontanman said:

Is there any chance we can discuss this report from Minot air base

It  would be great to return more to the OP topic, to which the 1968 Minot sighting is relevant.  Of the cases I've read about, it seems like one of the better documented, with trained observers, and pointing more strongly towards some kind of structured vehicle with flight characteristics inconsistent with 1960s level aerospace technology.  

There seem to have been other sightings also around Minuteman ICBM complexes, like the one at Malmstrom AFB over in Montana, a year earlier than the Minot sighting.

https://www.cufon.org/cufon/malmstrom/malm1.htm

In the Malmstrom case, and also in another one in 1966 at Minot, the ICBMs went offline and became unlaunchable for a while.

https://www.minotdailynews.com/news/local-news/2021/12/military-veterans-urge-truth-told-about-unidentified-aerial-phenomena-incidents/

Living in this part of the country, I have been aware of these strange events for a long time, and had conversations where there is speculation about them.  I have wondered if some sort of EMP device could have been involved, but other details pointing towards that seem lacking.  AFAIK, Minuteman missiles and the silo power supplies have always had pretty formidable Faraday shielding.  

 

.

 

 

 

 

Edited by TheVat
btpsglhk
Posted

Big coincidence, there was a prog on UK tv a couple of hours ago, on UFOs.

The part about sightings by three different airline crew, over Ireland really came across as genuine. They played the real-time audio recordings (they said) and there was no aroma of fakery about it at all, which is pretty rare. 

A relevant part of the program is on this youtube video, so see what you think

 

 

Posted (edited)

Astronaut and airline pilot sightings are quite abundant. But there never seems to be any particular investigative follow up by any leading experts (or so it appears). I'm quite amazed at how many sightings & sound for that matter have been witnessed by so many credible people. Including many from the space programs dating all the way back to the early 60's. 

I guess you can look at it 2 ways, all the sightings have been ignored, as nothing worth investigating. Or many if not most have been investigated and some of the information remains sensitive for one reason or another.

I'm quite skeptical of alien visitations, but the more reports I see, especially those from very credible sources, then I do start to wonder a little. 

I don't think we can discount it just because we currently think its highly improbable. All our investigative resources are based on our current understanding of physics. But we all know, that as successful as our models are, there are gaps. The gaps may turn out to be very insignificant.

All very speculative I know, but but one can't help but think - what if. 

   

Edited by Intoscience
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