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Close-in Sun orbiting mirrors for space solar power?

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#1 Robert Clark

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Posted 22 July 2024 - 12:01 PM

I may have asked this before but I couldn’t find it on a search on the site.

1.)There is a current push towards space solar power. Tell me why this wouldn't work: every school kid does the experiment where you focus sunlight down onto a spot using a handheld parabolic mirror to burn paper or wood. In fact its even possible to get the spot to reach the temperature of the surface of the Sun, ~3,000K, enough to melt steel, c.f., "solar furnace".

But suppose you had a mirror close in to the sun? Closer to the Sun you would get greater intensity for the same area. At Earth distance from the Sun, the solar intensity about 1,360 watts per square meter. (It's attenuated by clouds and so forth on the surface of the Earth, but this discussion is about space solar power anyway.) But if you had a mirrors 50 times closer to the Sun, about 3 million kilometers from the Sun, you would get 1,360Wx50^(2) = 3.4 megawatts per square meter. This would mean much smaller collecting area to get the same amount of energy. You would then using parabolic mirrors to focus this energy at Earth for collection.

But here's the key issue: as shown in the image you need parallel rays to focus the light to a point(actually an Airy disk). But light rays from the Sun are nearly parallel because of the distance from the Sun. But this is no longer true if your mirror is close in to the Sun.

So the question is how well would a parabolic mirror at such a closer distance focus the Sun light to a spot at collectors at Earth? The Sun's rays are not nearly as parallel so there is the question how well we can focus the light. Note there will be some degree of focusing by looking at the example of cameras. They can focus even light from light bulbs to some degree even though the light is dispersed.

So how well could we focus light sent from a much closer distance to the Sun all the way back to Earth? Would the Airy disk criterion of approx. 1.22*(wavelength)/(diameter) still hold?

Bob Clark

#2 Astrojensen

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Posted 22 July 2024 - 12:10 PM

Sooo, let me get this straight: We want to supply the grid with energy, produced by a few - or a single - megacorporations, by satellites in orbit that they have 100% control over.

What could possibly go wrong?

Clear skies!

Thomas, Denmark

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#3 bobzeq25

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Posted 22 July 2024 - 12:56 PM

Too expensive, and, as noted above, dangerous.  The goal is not simply power, it's cheap power, or, you'll just make power another way.  You can do this on Earth, much more cheaply and safely.  Using existing technology.  Simple flat mirrors, and a tower that pumps water up, converts it to steam, and runs a generator.

Simple technology, expense, and safety are some reasons why these are being built right now.  The most important reason is banned from discussion here.

Edited by bobzeq25, 22 July 2024 - 12:58 PM.

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#4 TOMDEY

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Posted 22 July 2024 - 01:01 PM

Bob, interesting topic! but there are multiple fallacies in your argument; I'll let others point out some of them... but encapsulated into one single gestalt, your proposal blatantly violates the restrictions imposed by Mother Nature, as brilliantly expressed in Emmy Noether's Theorem. On the other hand, you're at least in good company. Back in the 1970's and 80's I was called on to review gratuitous patent submissions arriving at my home base, Bausch & Lomb. One of them (already approved and issued!) nebulously referenced "Trilobite Lenses" which would somehow, magically(?) port the arriving flux from one region of the collector to another (smaller) region. A bit of algebra shows that the net gain of the all-passive system cannot possibly exceed --- unity. Yours suffers the same restriction, violating the Theorem, total integrated gain is less than one, regardless the details of the design.

There are two ways that your posit could work >>> 1) where your constellation of sun-proximate satellites morphs, in the limit, to a  Dyson Sphere, subtending an angle significantly larger than the sun's, as seen from earth or 2) one that involves a "positive gain transducer", which violates your "all mirrors" restriction. On a tiny scale, such transducers exist e.g. pumped lasers. All of these free lunch brainstorms violate either fundamental physics and/or practicality. It's also interesting that the Patent Office recently amended practicality to their allowance hurdles. Most inventors think this was always required, but it was previously a ~soft~ gate, now highlighted more formally.      Tom

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#5 T~Stew

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Posted 22 July 2024 - 03:01 PM

So how well could we focus light sent from a much closer distance to the Sun all the way back to Earth?

So you want to create a solar death ray, and shoot it at the Earth? Hoping to hit very precise collectors only? You know the Earth rotates, and tilted on axis. Just targeting specific suitable receivers sounds like an exercise in extinction of life on Earth. Well even if controlled targeting could work, it still kill any bird plane satallite insect etc in its path. And pray a micrometeor impact or soemthing doesn't skew it a bit and nuke a city.

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#6 Robert Clark

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Posted 22 July 2024 - 06:18 PM

Bob, interesting topic! but there are multiple fallacies in your argument; I'll let others point out some of them... but encapsulated into one single gestalt, your proposal blatantly violates the restrictions imposed by Mother Nature, as brilliantly expressed in Emmy Noether's Theorem. On the other hand, you're at least in good company. Back in the 1970's and 80's I was called on to review gratuitous patent submissions arriving at my home base, Bausch & Lomb. One of them (already approved and issued!) nebulously referenced "Trilobite Lenses" which would somehow, magically(?) port the arriving flux from one region of the collector to another (smaller) region. A bit of algebra shows that the net gain of the all-passive system cannot possibly exceed --- unity. Yours suffers the same restriction, violating the Theorem, total integrated gain is less than one, regardless the details of the design.

There are two ways that your posit could work >>> 1) where your constellation of sun-proximate satellites morphs, in the limit, to a  Dyson Sphere, subtending an angle significantly larger than the sun's, as seen from earth or 2) one that involves a "positive gain transducer", which violates your "all mirrors" restriction. On a tiny scale, such transducers exist e.g. pumped lasers. All of these free lunch brainstorms violate either fundamental physics and/or practicality. It's also interesting that the Patent Office recently amended practicality to their allowance hurdles. Most inventors think this was always required, but it was previously a ~soft~ gate, now highlighted more formally.      Tom

The total energy is the same as collected by the collecting mirror or lens. It is only focused on a smaller spot, the Airy disk. It’s the same thing that happens with a magnifying lens:

Melt a Penny with the Sun and a Fresnel Lens - (magnifying glass)

https://youtu.be/er3...Nlf-g5Vix7L7scs

It’s the principle Archimedes recognized 2,000 years ago:

13-year-old has eureka moment with science project that suggests Archimedes’ invention was plausible

By Taylor Nicioli, CNN
Updated 7:07 PM EST, Fri March 8, 2024

https://www.cnn.com/...-scn/index.html

And this start-up wants to place mirrors in space above the terminator to beam sunlight to locations that are in nighttime:

They're Making Solar Panels... Work at Night | Reflect Orbital
https://youtu.be/4Bc...exx3od7ptN1qr7j

Bob Clark

Edited by Robert Clark, 22 July 2024 - 07:15 PM.

#7 KBHornblower

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Posted 22 July 2024 - 06:55 PM

The total energy is the same as collected by the collecting mirror or lens. It is only focused on a smaller spot, the Airy disk. It’s the same thing that happens with a magnifying lens:

Melt a Penny with the Sun and a Fresnel Lens - (magnifying glass)

https://youtu.be/er3...Nlf-g5Vix7L7scs

It’s the principle Archimedes recognized 2,000 years ago:

13-year-old has eureka moment with science project that suggests Archimedes’ invention was plausible

By Taylor Nicioli, CNN
Updated 7:07 PM EST, Fri March 8, 2024

https://www.cnn.com/...-scn/index.html

Bob Clark

There is no way your hypothetical mirror can focus the Sun to an Airy disk.  The smallest possible spot from something near the Sun would subtend an angle of 1/2 degree as seen from the mirror.  That would be nearly a million miles across if focused on the Earth.  You would just cook the entire planet.

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#8 Bubbagumps

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Posted 22 July 2024 - 07:20 PM

Ignoring the technical feasibility and obvious issues just mentioned, such a system would be a potential train wreck logistically.

If you relied on such a solar orbiting system for your primary power needs, you put yourself at great risk of being caught with your pants down when something goes wrong with the dish you placed in orbit near the Sun. There is no viable contingency for timely repairs.  It's only a matter of time before something goes wrong.  You can't just call the electric company to send out a lineman to climb a pole.

You can't place a critical component in such a remote and inaccessible location and call it a day. Any Systems Engineer will be thinking about what-if. And the what-ifs in this case are all bad.

#9 TOMDEY

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Posted 22 July 2024 - 08:23 PM

The total energy is the same as collected by the collecting mirror or lens. It is only focused on a smaller spot, the Airy disk. It’s the same thing that happens with a magnifying lens:

Melt a Penny with the Sun and a Fresnel Lens - (magnifying glass)

https://youtu.be/er3...Nlf-g5Vix7L7scs

It’s the principle Archimedes recognized 2,000 years ago:

13-year-old has eureka moment with science project that suggests Archimedes’ invention was plausible

By Taylor Nicioli, CNN
Updated 7:07 PM EST, Fri March 8, 2024

https://www.cnn.com/...-scn/index.html

And this start-up wants to place mirrors in space above the terminator to beam sunlight to locations that are in nighttime:

They're Making Solar Panels... Work at Night | Reflect Orbital
https://youtu.be/4Bc...exx3od7ptN1qr7j

Bob Clark

Alas, Bob --- every one of those suffers fatal flaws > Emmy proves mathematically that no passive specular optical system (lenses, mirrors, gratings, etc. etc.) can achieve what you are seeking. At that juncture (thoroughly understanding the theorem) there is no point whatsoever in wading around in the weeds, scrutinizing each and every ~promising~ invention to find where (in the "teaching") its particular flaw lies. These inventors throw around baloney jargon like "Fresnel lenses", "Flat Lenses" etc. etc. without sufficiently knowing what they're talking about. The hypothetical "Trilobite Lenses" that the inventor was asking Bausch & Lomb to design were > theoretically impossible < therefore no need to try to design them. We (B&L) cordially thanked the inventor for showing us his patent... declined his offer... and wished him a pleasant day. In the inventor's defense... our own marketing and management guys occasionally asked us to design the impossible. We'd cordially point out why it couldn't possibly work, even in theory. This is one reason the big corporations keep a few research physicists on staff.

One of my specialties just happened to be non-imaging optical systems. I actually invented and designed numerous Fresnel lenses and mirrors. These became products for the lighting industries and my favorite uncle... Sam.    Tom

couple examples >>>

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#10 Robert Clark

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Posted 23 July 2024 - 05:57 AM

Alas, Bob --- every one of those suffers fatal flaws > Emmy proves mathematically that no passive specular optical system (lenses, mirrors, gratings, etc. etc.) can achieve what you are seeking. At that juncture (thoroughly understanding the theorem) there is no point whatsoever in wading around in the weeds, scrutinizing each and every ~promising~ invention to find where (in the "teaching") its particular flaw lies. These inventors throw around baloney jargon like "Fresnel lenses", "Flat Lenses" etc. etc. without sufficiently knowing what they're talking about. The hypothetical "Trilobite Lenses" that the inventor was asking Bausch & Lomb to design were > theoretically impossible < therefore no need to try to design them. We (B&L) cordially thanked the inventor for showing us his patent... declined his offer... and wished him a pleasant day. In the inventor's defense... our own marketing and management guys occasionally asked us to design the impossible. We'd cordially point out why it couldn't possibly work, even in theory. This is one reason the big corporations keep a few research physicists on staff.

One of my specialties just happened to be non-imaging optical systems. I actually invented and designed numerous Fresnel lenses and mirrors. These became products for the lighting industries and my favorite uncle... Sam.    Tom

couple examples >>>

It’s perfectly fine to use modifications that accomplishes the same thing more accurately. The point is for space solar power rather placing the solar stations in Earth orbit, they can be made many more times smaller by placing them close in to the Sun and beaming the power to Earth.

Bob Clark

#11 Robert Clark

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Posted 23 July 2024 - 09:19 AM

I’ll make comparison to the “Iridium flares”:

Iridium flares

First-generation Iridium satellite. Antennas can be seen in front, and solar panels in the back.
The first generation of the Iridium constellation launched a total of 95 telecommunication satellites in low Earth orbit which were known to cause Iridium flares, the brightest flares of all orbiting satellites, starting in 1997. From 2017 to 2019 they were replaced with a new generation that does not produce flares, with the first generation completely deorbited by 27 December 2019.[16][17]

While the first-generation Iridium satellites were still controlled, their flares could be predicted.[18] These Iridium communication satellites had three polished door-sized antennas, 120° apart and at 40° angles with the main bus. The forward antenna faced the direction the satellite is traveling. Occasionally, an antenna reflects sunlight directly down at Earth, creating a predictable and quickly moving illuminated spot on the surface below of about 10 km (6 mi) diameter. To an observer this looks like a bright flash, or flare in the sky, with a duration of a few seconds.
Ranging up to −9.5 magnitude, some of the flares were so bright that they could be seen in the daytime. This flashing caused some annoyance to astronomers, as the flares occasionally disturbed observations.[19]
As the Iridium constellation consisted of 66 working satellites, Iridium flares were visible quite often (2 to 4 times per night). Flares of brightness −5 magnitude occurred 3 to 4 times per week, and −8 magnitude were visible 3 to 5 times per month for stationary observers.

https://en.m.wikiped...#Iridium_flares

The key question is how wide would be the spot on the Earth? Would it be close to the size of the Airy disk? In this case it is well beyond the size of the Airy disk. The Wikipedia article gives it about 10 km across.

The antenna’s on the Iridium satellite flares are about the size of a door, so call them 2 m long. Say the wavelength of sunlight is 500 nm. The altitude of the Iridium satellites in 780 km. Then the Airy disk would be:

1.22*(500 nm)*(780 km)/2 m = .24 m, 24 cm.

But a reason the illuminated area would be larger is because the Iridium antennas are flat rather than having a parabolic surface like a focusing mirror or curved sides like a lens.

This might be better done by a lens where you are focusing light straight on rather than by a mirror, where it would be on a slant. We can calculate the size of a lens by the thick lens formula:

See for a diagram of a positive (converging) lens.

Thick Converging Lens: Diagram of a positive (converging) lens. The lensmaker’s formula relates the radii of curvature, the index of refraction of the lens, the thickness of the lens, and the focal length.

The focal length of a thick lens in air can be calculated from the lensmaker’s equation:

1/f = (n-1)[1/R1 - 1/R2 +(n-1)d/nR1R2]`

where
* P is the power of the lens,
* f is the focal length of the lens,
* n is the refractive index of the lens material,
* R1is the radius of curvature of the lens surface closest to the light source,
* R2 is the radius of curvature of the lens surface farthest from the light source, d and is the thickness of the lens (the distance along the lens axis between the two surface vertices).

https://phys.librete...cs/24.3:_Lenses

To get such a long focal length of ca. 780 km with only a 2 meter wide lens you would need in the range of a radius of curvature of ca. 100 meters and ca. 1 mm thickness.

This is doable. Something of this nature could be tested on Earth. If you have a lens of meters width and millimeter thickness and the focal length calculates out to be kilometers long. Is the observed focal spot close in size to the calculated Airy disk?

Bob Clark

#12 KBHornblower

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Posted 23 July 2024 - 09:58 AM

I miscalculated in a previous post.  For a mirror 50 times closer to the Sun, the Sun would subtend an angle of some 25 degrees, and the smallest possible focused image at Earth's distance from the mirror would be spread out about the same, some tens of millions of miles.  If you think I am wrong, please post a ray tracing sketch to illustrate why.

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#13 EJN

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Posted 23 July 2024 - 02:09 PM

But a reason the illuminated area would be larger is because the Iridium antennas are flat rather than having a parabolic surface like a focusing mirror or curved sides like a lens.

This might be better done by a lens where you are focusing light straight on rather than by a mirror, where it would be on a slant. We can calculate the size of a lens by the thick lens formula:

See for a diagram of a positive (converging) lens.

Thick Converging Lens: Diagram of a positive (converging) lens. The lensmaker’s formula relates the radii of curvature, the index of refraction of the lens, the thickness of the lens, and the focal length.
The focal length of a thick lens in air can be calculated from the lensmaker’s equation:
1/f = (n-1)[1/R1 - 1/R2 +(n-1)d/nR1R2]`
where
* P is the power of the lens,
* f is the focal length of the lens,
* n is the refractive index of the lens material,
* R1is the radius of curvature of the lens surface closest to the light source,
* R2 is the radius of curvature of the lens surface farthest from the light source, d and is the thickness of the lens (the distance along the lens axis between the two surface vertices).

https://phys.librete...cs/24.3:_Lenses

To get such a long focal length of ca. 780 km with only a 2 meter wide lens you would need in the range of a radius of curvature of ca. 100 meters and ca. 1 mm thickness.

This is doable. Something of this nature could be tested on Earth. If you have a lens of meters width and millimeter thickness and the focal length calculates out to be kilometers long. Is the observed focal spot close in size to the calculated Airy disk?

Bob Clark

The diagram you are showing is for a point source like a star. The sun is an extended object, from earth it is ~ 1/2 degree across. You can never get that to focus to an Airy disk.

The size of the solar image produced by a lens (or parabolic mirror) is
d = 0.009 * fl, where d is the diameter of the image produced of the sun (1)

For a focal length of 780 km, the size of the solar image would be 7 km, or 4.36 miles.

(1) A more general formula is:

d = 2 * tan(0.5 * ⍬) * flwhere  is the angular diameter of the object.

Edited by EJN, 23 July 2024 - 04:04 PM.

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#14 bobzeq25

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Posted 23 July 2024 - 03:22 PM

The total energy is the same as collected by the collecting mirror or lens. It is only focused on a smaller spot, the Airy disk. It’s the same thing that happens with a magnifying lens:

Melt a Penny with the Sun and a Fresnel Lens - (magnifying glass)

https://youtu.be/er3...Nlf-g5Vix7L7scs

It’s the principle Archimedes recognized 2,000 years ago:

13-year-old has eureka moment with science project that suggests Archimedes’ invention was plausible

By Taylor Nicioli, CNN
Updated 7:07 PM EST, Fri March 8, 2024

https://www.cnn.com/...-scn/index.html

And this start-up wants to place mirrors in space above the terminator to beam sunlight to locations that are in nighttime:

They're Making Solar Panels... Work at Night | Reflect Orbital
https://youtu.be/4Bc...exx3od7ptN1qr7j

Bob Clark

Gee, and people here think Starlink will be bad for astronomy.    It's not a drop in the bucket compared to this.  Musk actually works hard to make Starlink satellites LESS reflective.

Not to mention that the unavoidable spillover will make that which shall not be named here worse.  Takes away a major reason for doing solar in the first place.

The final straw is that it will make existing space junk look like a trivial threat.

Edited by bobzeq25, 23 July 2024 - 03:25 PM.

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#15 Bubbagumps

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Posted 23 July 2024 - 04:19 PM

Forget about whether you can make it work. Concentrating and then reflecting huge amounts of energy through large swaths of open space is an obvious recipe for disaster. You cannot control what might happen to pass in between the LOS of the collector and receiver. And if the system goes out of tolerance and angles get skewed, your experiment turns into a potential death ray that could roast a Space Station then proceed to set fires across large swaths of terra firma.

The hazards and pitfalls are obvious. It would be kind of like reverting to an energy source that relies on aircraft-based nuclear reactors flying over populated areas. Nothing will probably go wrong - for a while.

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#16 Robert Clark

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Posted 24 July 2024 - 06:53 AM

The diagram you are showing is for a point source like a star. The sun is an extended object, from earth it is ~ 1/2 degree across. You can never get that to focus to an Airy disk.

The size of the solar image produced by a lens (or parabolic mirror) is
d = 0.009 * fl, where d is the diameter of the image produced of the sun (1)

For a focal length of 780 km, the size of the solar image would be 7 km, or 4.36 miles.

(1) A more general formula is:

d = 2 * tan(0.5 * ⍬) * flwhere  is the angular diameter of the object.

That sounds like a reasonable explanation of the discrepancy. Here’s another approach. Lasers are known to have small divergence compared to ordinary light:

THE LASER BEAM DIVERGENCE FORMULA
For a circular Gaussian beam, the minimum achievable value of divergence (half-angle) is given by this simple formula:

θ0 = λ/π*ω0

In the equation above, λ is your laser wavelength and ω0 is the beam natural waist: its smallest dimension along the z-axis.
A Gaussian laser beam is said to be diffraction-limited when the measured divergence is close to θ0. To achieve the best aiming performance, that’s the goal!

https://www.gentec-e...nce-measurement

To create it close-in to the Sun use a solar-pumped laser:

https://en.m.wikiped...ar-pumped_laser

This uses sunlight to generate the power to run the laser. Close-in to the Sun there will be abundant power to run it. For the lasing medium, we can even use the plasma of the coronasphere.

The Parker Solar Probe shows we have capability for probes close in to the Sun. The Sun puts out 4x1026 watts. For its 700,000 km radius that’s 6.5x1013 watts per square kilometer. Humans use 17 terawatts, 17x1012, so only 0.26 square km, 500 m across, of the Suns solar output would need to be captured.

Using the above formula for the divergence of a laser beam, for a solar wavelength of 500 nm, and beam width of 500 m, the beam width once reaching the Earth would only expand to about 600 m.

Bob Clark

#17 Skywatchr

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Posted 24 July 2024 - 07:51 AM

The total energy is the same as collected by the collecting mirror or lens. It is only focused on a smaller spot, the Airy disk. It’s the same thing that happens with a magnifying lens:

Melt a Penny with the Sun and a Fresnel Lens - (magnifying glass)

https://youtu.be/er3...Nlf-g5Vix7L7scs

It’s the principle Archimedes recognized 2,000 years ago:

13-year-old has eureka moment with science project that suggests Archimedes’ invention was plausible

By Taylor Nicioli, CNN
Updated 7:07 PM EST, Fri March 8, 2024

https://www.cnn.com/...-scn/index.html

And this start-up wants to place mirrors in space above the terminator to beam sunlight to locations that are in nighttime:

They're Making Solar Panels... Work at Night | Reflect Orbital
https://youtu.be/4Bc...exx3od7ptN1qr7j

Bob Clark

Are you talking about "watts" in electrical energy?  Or watts in heat energy? The magnifying lens/mirror experiment to fry things, is concentrating the heat energy.

Putting "reflectors" beyond the terminator is a horrid idea.  It is akin to a Solar Oven that will heat up the Earth negating the Earth's ability to cool itself during the night.

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#18 Robert Clark

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Posted 24 July 2024 - 10:04 AM

Are you talking about "watts" in electrical energy?  Or watts in heat energy? The magnifying lens/mirror experiment to fry things, is concentrating the heat energy.

Putting "reflectors" beyond the terminator is a horrid idea.  It is akin to a Solar Oven that will heat up the Earth negating the Earth's ability to cool itself during the night.

I’m actually not a fan of the proposal either. I gave it as an example only of using mirrors to transport sunlight long distances.

Bob Clark

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#19 Skywatchr

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Posted 24 July 2024 - 10:10 AM

I’m actually not a fan of the proposal either. I gave it as an example only of using mirrors to transport sunlight long distances.

Bob Clark

I hope they realize the extreme error of their ways.

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#20 Robert Clark

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Posted 24 July 2024 - 10:12 AM

I miscalculated in a previous post.  For a mirror 50 times closer to the Sun, the Sun would subtend an angle of some 25 degrees, and the smallest possible focused image at Earth's distance from the mirror would be spread out about the same, some tens of millions of miles.  If you think I am wrong, please post a ray tracing sketch to illustrate why.

As ELN explained, I wasn’t taking into account the Sun is an extended object so my calculation looking at it as just a point source was incorrect.

I would appreciate your input on the idea of using close-in orbiting lasers to transport the close-in sunlight to the Earth’s vicinity.

Bob Clark

#21 bobzeq25

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Posted 24 July 2024 - 03:06 PM

I hope they realize the extreme error of their ways.

Like so many people, they're basically in it for the money.  They don't have to succeed to get paid big bucks for trying.

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#22 Skywatchr

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Posted 24 July 2024 - 03:31 PM

Like so many people, they're basically in it for the money.  They don't have to succeed to get paid big bucks for trying.

Or they are plain stupid.  Those that give them the money are perpetuating stupidity.

#23 bobzeq25

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Posted 25 July 2024 - 12:15 AM

Next up.

https://www.cloudyni...-grid-in-space/

#24 Robert Clark

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Posted 27 July 2024 - 11:49 AM

I miscalculated in a previous post.  For a mirror 50 times closer to the Sun, the Sun would subtend an angle of some 25 degrees, and the smallest possible focused image at Earth's distance from the mirror would be spread out about the same, some tens of millions of miles.  If you think I am wrong, please post a ray tracing sketch to illustrate why.

Yes. But if you think about it you really don’t have to image the entire disk of the Sun. As I mentioned, you only have to capture the light from a region 1/2 km wide to have enough energy to meet the total energy usage of humans. Now, imagine this as the region whose light you want to beam to Earth. You can certainly do it with lasers of that size as I mentioned in post #16. But suppose we want to do it with mirrors and lenses. Note we can even allow multiple light relay stations consisting of mirrors or lenses that are emplaced along the distance from the Sun to Earth. I’m thinking of the fact for instance a telescope has several lenses involved in getting the light from the source to the imagining lens.

So how could it work?

Bob Clark

Edited by Robert Clark, 27 July 2024 - 12:23 PM.

#25 EJN

EJN

Fly Me to the Moon

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Posted 27 July 2024 - 03:37 PM

Apparently you have overlooked orbital mechanics. How would you keep "relay stations" aligned with respect to Earth? They would be in their own solar orbits with different orbital periods.

Rube Goldberg would be proud of this idea.

If implemented, Acme Corporation should be the primary contractor and Wile E. Coyote the chief engineer.

Much simpler to run a wire to the center of the sun and use this circuit

Edited by EJN, 28 July 2024 - 02:06 AM.

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