Slashdot Mirror
U.S. Allows Sale of Half-Meter Satellite Photos
kreinsch writes "According to an article in today's Washington Post, the U.S. Government quietly granted a license to Space Imaging, Inc. two weeks ago to allow the sale of satellite photos with half-meter resolution, as compared to the current one-meter resolution available." As the article points out, this effectively ends the monopoly the spy agencies had on this high-end imagery.
However, the ultimate resolution of the spy satellites is not the only measure of their capabilities. For instance, can they image the exact same area continuously? Every 5 minutes? Every hour? Once a day? How large an area can they image at the highest possible resolution? How large an area can they image at a lower, but still useful resolution (for instance, for counting tanks or airplanes)?
My guess is that "scope time" or whatever the in-house jargon at the spy satellite agency is, would be very hard to get, and consequently ruthlessly rationed. I'd imagine perving on people sunbathing nude is generally ranked fairly low in the priority list.
Any sufficiently advanced technology is indistinguishable from a rigged demo
--Andy Finkel (J. Klass?)
A couple of months back I wrote a work of fiction speculating on the possibility that a *company* (rather than a government) was capable of constant surveillance of any individual. What would they do with it? Well, you know how amusement parks and such are always trying to sell you footage of you doing stuff? Maybe something like that. And of course, maybe some people would pay more NOT to have their activities visible...
Tweet, tweet.
actually we can. during the war in serbia/croatia a guy was interviewed on TV who stated they saw graves with humans in them from the spy sats. he stated that both male and female bodies were observed along with children. since the average human is around 1m or so and to differentiate female from male you have to image the upper chest area with sufficient resolution, you can deduce the res of the spy sats to be around 1/16 of a meter. of course, the cameras on board have to have a greater res than that to compensate for atmospheric disturbance etc. ...basically they should be able to make out the license plate on a car...but may not be able to read it.
In a word, no.
The instruments on Hubble are very very sensitive, capturing as many photons as possible. It's really designed for a completely different problem.
Looking at the earth, sun, or moon would SEVERELY damage the Hubble's optics, probably rendering much of its systems inoperable.
Doug
Venn ist das nurnstuck git und Slotermeyer? Ya! Beigerhund das oder die Flipperwaldt gersput!
I believe the company in question, space imaging, inc, is owned by lockheed and raytheon. Seeing as how these are two major US defense contractors, I don't see them trying to skirt US laws.
"They" have a resolution of about 10cm, according to the article. Not so shabby. Let's see... image quality goes as the square of the resolution, so quality would be about 25 [(0.5m/0.1m)^2] times better than half meter resolution.
This could be an indication that the 'spy agencies' or whoever now have access to even more sophisticated satellite-imagery, as 'obsolete' military technology tends to become avaliable to the public in one way or another.
You always get your pictures from space 24 hrs
late to make them unusable for tactical purposes
during times of war. AND I bet you 10 bucks the
US government gets every single coordinate from
which you requested shots to be taken. Maybe even
as soon as you submit them, so you can imagine
busy towing of new stuff into hangars once their
bird gets close for a shot.
Not that the Russians would care, their RESURS F14
is still flying over Groom Lake at an altitude of
230 km (82.1 deg steep inclination) with several
course corrections having been made.
Sometimes a who, what and when is more precious
than not letting them have the info in the first
place, which is getting harder because you can
already buy old 2m resolution birds anyway.
I think you will need finer resolution to actually be able to distinguish people. Unless you're trying to detect the presence of a (big) car or something. I suppose this also depends on the size of your mom, though.
Moz.
see a Text Widget
The resolving power of any telescope can be calculated by the formula Theta = 115.8/D, .05 seconds of arc.
.5 seconds of arc in most cases, although i'm not sure this is as critical for taking pictures of terrestrial objects as it is for astronomical ones. I'm sure someone will correct me if I'm wrong on any of this.
.^
where Theta is angualr resolution expressed in seconds of arc, and D is the diameter of the objective of the telescope/camera, which is what a spy satellite is. Now, the Hubble telescope has an objective of 2.4 meters, which is probably pretty close to the maximum diameter that will fit inside current launch vehicles, so the NRO satellites can't be much bigger than this. so that works out to around
to figure out actual size from angular size and distance use the formula
angular size(in degrees) = 57.3*actual size / distance
which works out to right around 10 centimeters, if i've done the math right. so unless they have multi-segment meirros for their satellites or some other unknown capability that is about hte theoeretical limit of their resolution. Interestingly though, atmospheric turbulence (what astronomers refer to as 'seeing') limits actual performance to
^.
( @ )
Soylent Foods, Inc.
The limit of resolution on a camera is the diffraction limit. That's the point where the wavelength of the light is larger than the angular distance of the object you're viewing. The formula is (angular resolution) = 1.22 * (wavelength)/(telescope diameter) in radians. To convert radians to length, multiply by the distance from your target (which is a good approximation at large distances.)
:)
Most low orbit satellites are about 700 km up. Visible light is around 300-600 nanometers...call it 400 nm.
So the theoretical minimum telescope needed to have a one-centimeter resolution on the ground would be diameter = 1.22*400e-9*700e3/1e-2, or about 34 meters across. For reference, the Hubble's mirror is 2.4 meters diameter.
So it's possible. Just not bloody likely given current limits on what we can build in space.
Genocide Man -- Life is funny. Death is funnier. Mass murder can be hilarious.
A company should not need a license to sell photographs that it took with a satellite that it designed, built, and owns. The US government does not own the entire planet.
I don't think it's *that* detailed, guys.
Here's one of the early "meter" images.
Sure, you can see the road, and big buildings, but you can't really identify a person...
---
pb Reply or e-mail; don't vaguely moderate.
pb Reply or e-mail; don't vaguely moderate.
Not true. To get a 5-mm-resolution 500x500 image from a height of 300 km, you'd have to have a field of view of 0.03 arc seconds. For comparison, atmospheric turbulence normally makes it pointless to try to make telescopic images with fields of view of less than about 1000 arc seconds. That's why the Hubble Space Telescope got built -- to do astronomy without that nasty atmosphere in the way.
Nevertheless, whith that resolution you can get enough information about goods productions, plantations, petrol explorations, building surfaces, electric/energy installations, radio installations, satellital antennas (which are forbidden in some countries), and so on.
If someone's afraid of the secret police knocking on his door about his satellite antenna, I think he has more to worry about from neighborhood informants than from space-based imaging. He could always put his satellite antenna under a blanket or something.
I am not afraid of my privacity, I don't have anything important to hide, but privacity, in the sense that is technological expensive to peep you, is a fundamental value in most of "western minds"*.
You need to be realistic about the privacy you expect. When you do something outdoors, you don't normally have an expectation of privacy.
Find free books.
Does this bug other people as much as it does me?
Half-meter resolution doesn't mean that it "clearly shows objects as small as 19 inches!" This is quite misleading.
It simply means that an object of 19 inches can register in the image- and "register" simply means that a dot on the image might be brighter or darker depending on the overall colour of the object.
"To clearly show an object" implies that you'll be able to identify it. Some might even think that you'd be able to see features and details of the object. Nothing could be further from the truth.
This is better:
At half-meter resolution... forestry officials can count trees, and urban planners can view streetscapes, even discerning manhole covers.
But I wish they had put that at the top of the article, not at the end of the last paragraph!
--
Accountability on the heads of the powerful.
Power in the hands of the accountable.
Of course, the optical resolution doesn't really matter, they can always zoom in the picture to get more detail. You know, like they do on The X-Files.
--