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Yes. My understanding of these things based mostly on trolling through the various digital imagery company websites, is that many of the small satellites can ge

Yes. My understanding of these things based mostly on trolling through the various digital imagery company websites, is that many of the small satellites can generate detail as good as the "big guys" (at least as far is known in open sources) by using a telescopic lens. The difference however is aperture. Given the size of the optics on a small satellite the amount of area it can cover at 1 meter per pixel resolution is much smaller than something with a very large aperture could. As a result if you take a 10 Mpixel image with 1 meter per pixel accuracy that is a region roughly 3.2km on a side. Not a particularly large area.

bartwe 6y ago
Do the small sats have an advantage by being closer to the target, needing less zoom?
- xvedejas 6y ago
  Higher orbits are much more expensive to launch a satellite into. I think partially because of this, commercial imaging satellites will be in the range of 600-800km altitude unless there's a really good reason otherwise. So I don't think that distance would account for a very large factor.
- Fordec 6y ago
  Yes. The difference between 100k-400km in LEO is far different from 22000km in GEO. Planet Labs updated their licenses for a few satellites a couple of months back to gain double digit percentage resolution quality increases by dropping the orbit (I think it was somewhere about by 50km to the lower end of that range) for example. The trade off is that you hit more atmosphere in that lower orbit and will reenter the atmosphere much sooner. So that increases the number of launches you need to do to replenish your fleet. Which is $$$. Also, they have greater relative velocities so require better targeting and command & control technology to compensate.
garmaine 6y ago
Nothing open source can take images anywhere near the capability of spy satellites. We learned this when Trump tweeted an image of the Iranian missile/launch vehicle disaster.
LargoLasskhyfv 6y ago
Maybe [1] https://en.wikipedia.org/wiki/Superlens https://en.wikipedia.org/wiki/Superlens & [2] https://en.wikipedia.org/wiki/Negative-index_metamaterial https://en.wikipedia.org/wiki/Negative-index_metamaterial can change that? Also I'm sometimes wondering what happened to Holography, and if something like [3] https://en.wikipedia.org/wiki/Invention_Secrecy_Act https://en.wikipedia.org/wiki/Invention_Secrecy_Act came into play?
- Fordec 6y ago
  There's also rules on launching a satellite with capabilities below 10m per pixel on the basis of national security. At least if you're an American company anyway, can't vouch for elsewhere but they're a bit behind the tech curve (at least in the private sector) in this field (but not by much) so it hasn't really come up yet as an issue so far. There was an image that Trump tweeted a satellite image about something in Iran a while back, I forget the actual reason. But it was a declassified image of something and some keen eyed observers did some analysis on it and concluded the resolution was better than what is "Officially" out there. So it's safe to say there's better out there that we just don't know about yet.
  - LargoLasskhyfv 6y ago
    Rocket blew up on pad during launch. [1] https://www.thedrive.com/the-war-zone/29634/trump-tweets-intelligence-image-after-irans-rocket-explosion-and-offers-them-best-wishes https://www.thedrive.com/the-war-zone/29634/trump-tweets-int... Made me think of the movie "Enemy of the State" from 1998, and another action/sci-fi B-Movie from before 1980 which I can't remember the title anymore because forgettable, except of the FLIR inserts they made. Which were as good as anything you can personally buy today as private person. In a B-Movie! From before 1980! (Maybe even 1975/76) W-T-F? I really can't remember the title anymore, because "loading, looking, lösching!" (loading, watching, erasing)

bartwe 6y ago

Do the small sats have an advantage by being closer to the target, needing less zoom?

xvedejas 6y ago
Higher orbits are much more expensive to launch a satellite into. I think partially because of this, commercial imaging satellites will be in the range of 600-800km altitude unless there's a really good reason otherwise. So I don't think that distance would account for a very large factor.
Fordec 6y ago
Yes. The difference between 100k-400km in LEO is far different from 22000km in GEO. Planet Labs updated their licenses for a few satellites a couple of months back to gain double digit percentage resolution quality increases by dropping the orbit (I think it was somewhere about by 50km to the lower end of that range) for example. The trade off is that you hit more atmosphere in that lower orbit and will reenter the atmosphere much sooner. So that increases the number of launches you need to do to replenish your fleet. Which is $$$. Also, they have greater relative velocities so require better targeting and command & control technology to compensate.

garmaine 6y ago

Nothing open source can take images anywhere near the capability of spy satellites. We learned this when Trump tweeted an image of the Iranian missile/launch vehicle disaster.

LargoLasskhyfv 6y ago

Maybe [1] https://en.wikipedia.org/wiki/Superlens https://en.wikipedia.org/wiki/Superlens & [2] https://en.wikipedia.org/wiki/Negative-index_metamaterial https://en.wikipedia.org/wiki/Negative-index_metamaterial can change that? Also I'm sometimes wondering what happened to Holography, and if something like [3] https://en.wikipedia.org/wiki/Invention_Secrecy_Act https://en.wikipedia.org/wiki/Invention_Secrecy_Act came into play?

Fordec 6y ago
There's also rules on launching a satellite with capabilities below 10m per pixel on the basis of national security. At least if you're an American company anyway, can't vouch for elsewhere but they're a bit behind the tech curve (at least in the private sector) in this field (but not by much) so it hasn't really come up yet as an issue so far. There was an image that Trump tweeted a satellite image about something in Iran a while back, I forget the actual reason. But it was a declassified image of something and some keen eyed observers did some analysis on it and concluded the resolution was better than what is "Officially" out there. So it's safe to say there's better out there that we just don't know about yet.
- LargoLasskhyfv 6y ago
  Rocket blew up on pad during launch. [1] https://www.thedrive.com/the-war-zone/29634/trump-tweets-intelligence-image-after-irans-rocket-explosion-and-offers-them-best-wishes https://www.thedrive.com/the-war-zone/29634/trump-tweets-int... Made me think of the movie "Enemy of the State" from 1998, and another action/sci-fi B-Movie from before 1980 which I can't remember the title anymore because forgettable, except of the FLIR inserts they made. Which were as good as anything you can personally buy today as private person. In a B-Movie! From before 1980! (Maybe even 1975/76) W-T-F? I really can't remember the title anymore, because "loading, looking, lösching!" (loading, watching, erasing)