Streetlights, but from Space

[Shpaget]

https://www.theguardian.com/science/2018/oct/17/chinese-city-plans-to-launch-artificial-moon-to-replace-streetlights

So, someone thinks it would be great if they could put a satellite up there that would shine down on Earth during the night to produce "dusk-like glow" which is, according to the article about 8 times as bright as moonlight.

With moonlight being about one millionth as bright as Sun, it would take about 800 kW to power this monstrosity. That's 10 times the size of ISS solar array.

Now, how to we cool this thing down?

[kerbiloid]

Spoiler

Not politics, but some Chinese city would probably await a tax inspection.

 

[Cassel]

Best way to block ability of common person to observe stars?

[Lisias]

2 hours ago, Cassel said:

Best way to block ability of common person to observe stars?

Not to mention the impact on fauna and flora.

[YNM]

False flag, people ! It's the giant land-burner !

Edited October 18, 2018 by YNM

[magnemoe]

An giant mirror should be able to do this too and cheaper, bonus is that you can put it in an higher orbit, geo might be an option. 
Soviet thought about it for some areas in Sibir. 

 

[YNM]

In any case, I'd argue such concentrated-light contraptions should count under space weapons.

[Cassel]

1 hour ago, magnemoe said:

An giant mirror should be able to do this too and cheaper, bonus is that you can put it in an higher orbit, geo might be an option. 
Soviet thought about it for some areas in Sibir. 

 

Yes, but it turned out to be cheaper to spray from balloons substances focusing the solar energy ;-)

Edited October 18, 2018 by Cassel

[Shpaget]

1 hour ago, magnemoe said:

An giant mirror should be able to do this too and cheaper, bonus is that you can put it in an higher orbit, geo might be an option. 
Soviet thought about it for some areas in Sibir. 

 

Sure, it would still need to be very large. Not inconceivably large, but about twice the size of ISS array, plus control mechanism.

1 hour ago, YNM said:

In any case, I'd argue such concentrated-light contraptions should count under space weapons.

Not at this power level. If it can concentrate all its power to an area of 100 m^2 (10 m x 10 m square) it would deliver 8 kW/m^2 which would give you a decent tan, but is far from death-ray. For example, industrial fiber lasers (that are in several kW power range) focus all that energy to a tiny spot of about 0.1 mm^2. That means the energy density is on the order of 10 million times higher.

[kerbiloid]

Spoiler

If launch a disco ball they can illuminate all their cities.

 

Edited October 18, 2018 by kerbiloid

[Ultimate Steve]

Everyone freaks out about Rocket Lab's tiny insignificant blinking disco ball, imagine the backlash if this were launched...

[YNM]

19 hours ago, Shpaget said:

Not at this power level.

You can't be too sure of their true capabilities...

I'd prefer to die another day than a space streetlight today.

Edited October 19, 2018 by YNM

[insert_name]

How would they keep it over the city if its not equatorial?  Also this seems like it would throw off a lot of star  and moon trackers on spacecraft,  causing all sorts of diplomatic issues. Not to mention that the size of this thing would make JWST look like a childs toy.

[Mad Rocket Scientist]

Is it really that expensive to install streetlights? The largest issue I think would be the impact on animals which rely on the moon (or darkness) for stuff. Also people with skylights who want to sleep. It does say this in the article: "the precise illumination range could be controlled within tens of metres" although it's unclear how that would be:

a) Possible

b) Cheaper than streetlights, even over 100s of years of electrical costs

c) Not a weapon

This reminds me of the time I considered using airships with IR spotlights and night-vision contact lenses for every citizen to replace streetlights.

[Reactordrone]

A new Znamya. Should be an interesting test if nothing else.

https://www.reddit.com/r/space/comments/6gnilu/progress_spacecraft_testing_the_cosmos1/

 

[YNM]

5 hours ago, Mad Rocket Scientist said:

"the precise illumination range could be controlled within tens of metres"

I'll be damned if Eon Productions managed to get an idea years before they went for it.

[sh1pman]

Cool stuff.

Quote

The plan from Chinese leaders is to put three small, highly reflective satellites in orbit by around 2020. These satellites would reflect light at night and be be around 8 times brighter than the light from a full moon, enough to brighten the streets of Chengdu without spending any electricity on lighting. Such a plan, if it works, could save the city nearly $250 million in electricity costs per year, more than enough to justify the cost of the satellites.

Even though Chengdu wants three reflective satellites, they wouldn’t all operate at the same time. They’d work on a rotation, and only one would light up the city at a time. Each satellite would provide light in a circle between 6 and 25 miles wide, enough to guarantee coverage of at least the inner city, and sometimes enough to cover the entire metropolitan area.

Officials also stated that these satellites could also be used to light up areas that don’t receive much artificial lighting, like rural areas or the sites of disasters like earthquakes or hurricanes. That’s assuming that they work as intended, of course. But if they do, it could help plenty of other cities end the scourge of light pollution.

https://www.popularmechanics.com/space/satellites/a23903386/china-moons-reflective-satellites-street-lights/

[Nuke]

how many astronauts does it take to screw in a light bulb?

[Rakaydos]

Out of curiosity, what would be the spread of overlapping red/green lasers from LEO or GEO to the surface? Would it be plausable to illuminate a single street with an orbital laser array? (assuming it was never cloudy)

[Nightside]

4 hours ago, sh1pman said:

But if they do, it could help plenty of other cities end the scourge of light pollution.

Seems more like light pollution on a planetary scale.

[sh1pman]

10 minutes ago, Nightside said:

Seems more like light pollution on a planetary scale.

Cool stuff nonetheless.

[Shpaget]

https://www.nextbigfuture.com/2018/10/chengdu-launching-satellite-to-create-8x-full-moon-lighting.html/amp

It's getting crazier.

Now they are talking about eventually having this thing illuminating ground based solar farms 24/7, presumably at daylight illumination level.

[Ultimate Steve]

23 minutes ago, Shpaget said:

 

Now they are talking about eventually having this thing illuminating ground based solar farms 24/7, presumably at daylight illumination level.

Hmm... If we put the farms where nobody lives, this I could actually get behind. But don't plants use the day/night cycle as a regulator for breathing, or am I remembering?

[Gargamel]

6 minutes ago, Ultimate Steve said:

Hmm... If we put the farms where nobody lives, this I could actually get behind. But don't plants use the day/night cycle as a regulator for breathing, or am I remembering?

I believe you are correct, but at the very least, a variety of animals rely on the day night cycle. 

 

[YNM]

1 hour ago, Shpaget said:

Now they are talking about eventually having this thing illuminating ground based solar farms 24/7, presumably at daylight illumination level.

Looking even more this way then.