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My camera is not an a7r. I paid $1200 for it used. The exposure was 10 seconds, so by your own explanation, the spinning of the earth is not a problem ( as you can clearly see in the photo I linked )
An astronomy photo can commonly require hours or even tens of hours of exposure time.
"Stitching together 343 distinct photos," I don't doubt that this is a real problem for astronomers and photographers, but I feel like if you had to work that hard, it doesn't really make your case.
In his defense, he was shooting a star trail. @10s per exposure, 6 per minute, becomes 360 per hour. I believe 30s might be more appropriate for star trails which makes satellite trails oh so much more obvious. But that means a 2-3 hour session of 2 exposures per minute. I also used to take hundreds of photos in meteor season - and having to diff between meteors and satellites was quite time consuming.
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This is a single 10sec exposure in the Aussie outback on old consumer gear ( Sony a7iii ) https://www.instagram.com/p/CersLuLBfCz You don’t need multiples, and you don’t need an overly long exposure.
It sounds like you know what you're talking about until one realizes the earth is spinning. Wide field photos can be shot up to thirty seconds depending on the back and lens. Anything more zoomy than 50mm uncropped you're getting streaks in Best course of action is to take a video and let a stacking program deal with it, especially if you use a real telescope. Also the Sony a7r have like "150,000 ISO " and iirc cost…
Some random search result:
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It isn't that simple, is it? Even if you place the black surface on a spacer (adding mass, might I add), the black surface itself is going to radiate heat back onto the satellite via blackbody radiation. This is always going to create a worse thermal situation unless you can somehow radiate away as much heat as you could with reflections. To see what I mean, check out JWST's thermal shield.
Consider a shaped charge. It seems wild to me that you can direct an explosion with various shapes of the explosive. Perhaps a similar idea can apply to the blackbody radiation - get it to radiate mostly away from the satellite. Also, the black part will be pointed at the Earth, not the Sun.
If it's just an asymmetric shape, with different material surfaces pointed in different directions, than that of course is permitted.
https://en.wikipedia.org/wiki/Kirchhoff%27s_law_of_thermal_r...
You know those airplanes with a banner at the beach? I can imagine a constellation of satellites writing ads (live) in space using mirrors and other nifty tech. Unless regulation stops it.
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An astronomy photo can commonly require hours or even tens of hours of exposure time.
The noise from a single image of that duration would be unworkable. Even if there were no planes or satellites, nobody would take that as a single exposure.
(This is a simplification, there are many types of noise including shot noise and thermal noise, but in general this is the rule of thumb you use)
The clear grid patterns are really fantastic. (I realise that it's bad and all that - but still, those grids are amazing to see)
You know those airplanes with a banner at the beach? I can imagine a constellation of satellites writing ads (live) in space using mirrors and other nifty tech. Unless regulation stops it.
I’m fine with putting dots in the sky as a necessary side effect of providing some sort of useful service. Worldwide connectivity seems worth making astronomical observations a bit harder. But visual pollution for its own sake should be harshly discouraged.