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Last year I was part of a team that did some work on debris in the GEO belt. Using the INT we were still spotting debris objects down to mag 20/21. It didnt look like the population was tailing off even then. But without being allocated time on a bigger scope its hard to know.
Well, as the satellites are not illuminated by the sun after twilight in the winter, the winter may become the best time for long exposure wide angle imaging. Mid-summer is going to be horrific if thousands of these things go up.
As I recall, one of the Musk sats has a new paintjob that is supposed to be lower albedo. Does it look obviously dimmer? Has anyone observed it yet? My best guess is that if they will have managed an attentuation of the order of 2-2.25 mags. So they will still be bright enough to ruin almost any telescopic image.
The ordure is really going to encounter the ventilation system when they start failing, attitude control is lost and the tumbling starts. Some of the flares are going to be impressive. But hey, its okay, someone will get rich on the back of this.
A supernova at that distance is going to be pretty bright. Are any wavelengths reaching us likely to cause problems?
Happy Christmas/Hannukah/Saturnalia/Yule/Solstice
Thats really worth knowing. I have previously steered clear of trying to solve images with severely trailed stars assuming it would say “Sorry guv, no stars in here”.
Stop Press: seems to depend on the aspect ratio of the trails. The longer a trail is compared to its width the less likely it is to solve. Still worth knowing that Astrometry.net can be quite tolerant.
I was wondering how you did that. In the earlier pictures the stars were starlike but images 9-11 contained significantly trailed stars. Is astrometry.net really that forgiving/tolerant or did you extract some positions manually as a text list?
Even if they push the albedo from (say) 70% to 10% thats only going to be 2 and a bit magnitudes, so you go from a 3rd mag satellite mucking up your images to a 5th mag. Great.
Given that even geosats mess up deep sky images (and they are normally 8th mag or fainter) I’m not seeing much benefit.
The problem is he has a business plan to make money. What is his incentive to stop?
If we said anything, I wonder what he would call us?
Ah, I see. A 20 min running average certainly helps.
Impressive. Noise level at the 8-10mmags level perhaps.
This seemed appropriately timed: https://www.xkcd.com/2202/
Was it cellulose acetate or cellulose nitrate (nitrocellulose) that was the problem? Nitrocellulose was quite widely used in the early years of the 1900s.
I imagine cellulose acetate can burn but, nitrocellulose is also known as gun cotton and burns with vigour!
Without the addition of carbamite or another stabiliser, the decomposition products of nitrocellulose accumulate quite quickly making film go brownish – so colour film would really suffer.
Didnt some types of billiard ball made from nitrocellulose during the 20’s have a similar issue? I have a vague memory nitrocellulose was used as a coating for playing cards as well at some point.
