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

[Shmel]

Come on! The amount of mirror required plus the propulsion/guidance system required is well past anything we presently are capable of - year 2525 - maybe.

This is stuff from science fiction - from a rather poor selling author.

This stuff is a science fiction which was actually implemented in reality 20 years ago. Couple of hundred meters wide mirror is not that big and absolutely possible to put onto orbit. And it also serves as a solar sale allowing a satellite to maneuver on the orbit.

[Sunking]

This stuff is a science fiction which was actually implemented in reality 20 years ago. Couple of hundred meters wide mirror is not that big and absolutely possible to put onto orbit. And it also serves as a solar sale allowing a satellite to maneuver on the orbit.

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

[russ]

This stuff is a science fiction which was actually implemented in reality 20 years ago. Couple of hundred meters wide mirror is not that big and absolutely possible to put onto orbit. And it also serves as a solar sale allowing a satellite to maneuver on the orbit.

You are dreaming about the cost and the practicality! Doing something on a mini scale and comparing it to a super size unit has no meaning whatsoever.

A functional and useful unit was NOT implemented twenty years back - a toy like DIY panels may have been.

Positioning equipment in orbit is not so easy as you might suggest - solar sail (not sale - that is Walmart) is of marginal use in some cases.

Totally a useless proposition - you must be one of the loony left voters?

[Shmel]

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

Can not find any budget information on Russian Znamya satellites, but Japanese IKAROS, which was driven by solar sail, which is basically a big mirror, did cost 16 million to build. This is cost of average research project.

[Shmel]

Totally a useless proposition - you must be one of the loony left voters?

You must be a freaking internet telepath, ah?

You may mumble whatever you want, dude, but orbital mirrors and solar sails are not a fiction, but ongoing research, and probably better investment than those multimillion few megawatts solar power plants which were build plenty during recent years.

[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.

[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.

[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.

[Shmel]

I spent a lifetime working on projects

Go and buy yourself a copper medal now.

"Projects", my ass.

[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.

[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.

[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?

[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.

[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.

[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.