Lighting the dark (night) areas on earth with sun light conveyed from bright areas?

[axis11]

[QUOTE=Shmel; the idea was to have a swarm of several mirrors at low orbits which together were supposed to illuminate several different sites in different time zones. [/QUOTE]

This is one of the reasons the project was abandoned. That swarm of mirrors beamed to a single point would be perfect weapon of mass destruction, same as mentioned earlier.

[inetdog]

Yep - Had my first connection in 1982. Advanced tech is great - fuzzy headed thinking is fuzzy headed thinking. Too many get confused between advanced and fuzzy.

Corollary 2 of Clarke's Law: "Any technology distinguishable from magic is insufficiently advanced."

[russ]

So was this very Internet you are currently using to complain about how advanced technology is pure fantasy.

Yep - Had my first connection in 1982. Advanced tech is great - fuzzy headed thinking is fuzzy headed thinking. Too many get confused between advanced and fuzzy.

[billvon]

Would you say the required Federal Specification of Interstate Highways passing through a metropolitan area lighting system? Enough light to make out an object (no details, just an object) at 1000 feet sound about right? Be careful how you answer cause I am giving you rope to hang yourself.

I have no intention of trying to meet any federal standards; not all that much a fan of letting government bureaucracy dictate technology. You can do so if you like.

Overall I'd be aiming for about 5 lux or about 5 times the illumination that the Moon provides at low latitudes. That's generally considered adequate for roads, and is around .01% of the intensity of sunlight. (Although I am sure it does not meet some bureaucrat's CYA requirements.) Thus you could lose five orders of magnitude worth of energy density from the mirror to the ground.

[Shmel]

Orbital mirror does not have to be geosynchronous. It should rise before sunset and go beyond horizon after sunrise. This brings the orbit to about 15 thousand miles. If two mirrors illuminate the same site, orbit would be roughly 10 thousand miles. From sparse information about Znamya project I understand that the idea was to have a swarm of several mirrors at low orbits which together were supposed to illuminate several different sites in different time zones. This was absolutely plausible project, and it is very sad that it was abandoned.

[Sunking]

It's a glowing orb in the night sky lighting up a city! It should clearly be shot down.

You have no idea what you are talking about. What would you say a good light level should be at the surface?

Would you say the required Federal Specification of Interstate Highways passing through a metropolitan area lighting system? Enough light to make out an object (no details, just an object) at 1000 feet sound about right? Be careful how you answer cause I am giving you rope to hang yourself.

[billvon]

How do you and most of the population sleep, when the Moon is shining?

It's a glowing orb in the night sky lighting up a city! It should clearly be shot down.

[billvon]

Huh? A glowing orb in the night sky lighting up a city you call a concern? To me and most of the population would call that an act of WAR to be shot down with a missile.

Yep. People thought the same about Sputnik. I'm sure there are a few people who think the ISS should be shot down. (It's TRESPASSING over our country and taking pictures! It's an act of WAR!)

Anyway the whole subject is pointless. To do it would require a geosynchronous orbit at 25,000 miles above the earth. The reflector would have to be enormous the size of a small state to reflect enough light to the surface to illuminate a single city with dim light.

Agreed. And it needn't be more than a few molecules thick.

It is pure fantasy of a Sci-Fi book.

So was this very Internet you are currently using to complain about how advanced technology is pure fantasy. I've found it's generally a mistake to bet against progress.

It would also be seen as a weapon of mass destruction. If you have enough precision to position it and keep it perfectly flat, you can change the shape to parabolic to concentrate the light onto a small area like a city block and vaporize it in a few seconds.

Physics, my good man, physics! Do the math; you'll find it's not possible.

[Shmel]

Huh? A glowing orb in the night sky lighting up a city you call a concern? To me and most of the population would call that an act of WAR to be shot down with a missile.

How do you and most of the population sleep, when the Moon is shining?

[Sunking]

I don't know that it would be much different from having a streetlight near your house.

Huh? A glowing orb in the night sky lighting up a city you call a concern? To me and most of the population would call that an act of WAR to be shot down with a missile.

Anyway the whole subject is pointless. To do it would require a geosynchronous orbit at 25,000 miles above the earth. The reflector would have to be enormous the size of a small state to reflect enough light to the surface to illuminate a single city with dim light . It is pure fantasy of a Sci-Fi book.

It would also be seen as a weapon of mass destruction. If you have enough precision to position it and keep it perfectly flat, you can change the shape to parabolic to concentrate the light onto a small area like a city block and vaporize it in a few seconds.

[billvon]

Not in my city thank you. I am one of those people who cannot sleep when it is light out. There is a reason God made day and night. One of them is so I can sleep.

I don't know that it would be much different from having a streetlight near your house. But that issue (light pollution) would definitely be a concern.

[Shmel]

I spent a lifetime working on projects

Go and buy yourself a copper medal now.

"Projects", my ass.

[Sunking]

In most cases it won't make sense financially. But if you had a big city that could be lit this way it might make a lot of sense.

Not in my city thank you. I am one of those people who cannot sleep when it is light out. There is a reason God made day and night. One of them is so I can sleep.

[billvon]

So when are you going to cough up around $1 Billion dollars to do that?

From saving the $2 billion a year we currently spend on streetlights, perhaps?

In most cases it won't make sense financially. But if you had a big city that could be lit this way it might make a lot of sense.

Let's look at LA. Over 2 million streetlights. Let's assume each streetlight costs about $2000 to install. That's 4 billion dollars in capital costs - and $100 million in power costs per year - the city could save. Could 4 billion buy a heliostat in geosynchronous orbit? Well, a Delta IV Heavy launch will set you back about $250 million and will deliver 12 metric tons to GTO. That leaves 3.75 billion for the heliostat itself - and that could pay for a lot of development.

[russ]

You are talking about toys 'dude'. I spent a lifetime working on projects - what you so easily throw out as you have no idea what you are talking about happens to be important. Like I said - 2525 and you can make book on that. Scaling up from toy to major is never straight forward and never easy - not to mention how many tons of space junk are flying by up there to shred any large object.

Green fuzzy headed thinking is useless stuff.