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The next generation WorldView-2 satellite from DigitalGlobe will have a 'Coastal' band (450 - 500 nm) in addition to the Blue, Green, Red and Near-IR bands, specifically to improve this capability (it will have additional Near-IR bands as well).

Radar, as other correspondents point out is not much use in water, but it has been used to study desert sites, such as Ubar in Southern Oman. (This may be in TFA but I still can't get to it...)

The next generation WorldView-2 satellite from DigitalGlobe will have a 'Coastal' band (450 - 500 nm) in addition to the Blue, Green, Red and Near-IR bands, specifically to improve this capability (it will have additional Near-IR bands as well).

Radar, as other correspondents point out is not much use in water, but it has been used to study desert sites, such as Ubar in Southern Oman. (This may be in TFA but I still can't get to it...)

QuickBird, launched 2001, has a 60cm pixel and a swath of 16.5 km. WorldView-1, launched last Thursday, and WorldView-2 (late 2008) have similar swaths and 50cm pixels. The main limit on resolution has been legislative (i.e. U.S. Govt.) and political, not technical. You can't get video from a satellite, of course, because it's in orbit (450km for QuickBird, 770 for WorldView-2 -- orbital period around 90 mins) and only sees the target for a few minutes and anyway each scene is around 2Gb. This Sony camera seems to have nothing to do with satellites. Satellite sensors are more like scanners than cameras. There's a guide to VHR satellite imaging here. Commercial missions use sun-synchronous orbits for consistency -- the satellite passes overhead at the same local time, usually around 10-11 a.m. Military (Keyhole) sats can produce a smaller pixel but they use highly elliptical orbits and... wait... what are those black helicopters outside my window... listen, I was just....

This is nonsense: I work in the earth observation satellite industry and there are no ultraviolet or x-ray sensors on earth observation satellites (for obvious reasons - the earth does not emit x-rays, and UV is absorbed by the atmosphere.)
Optical sensors can see at most a few metres into clear water. At infrared wavelengths water is black and opaque. "Light passes through matter"? No, it doesn't. Didn't The Times use to have a science correspondent?

... on-line, in various places. The University of Maryland has a fairly complete set of Landsat 5 and 7 data, all bands, available via ftp (not my place to give out the url, though).

Landsat 7 has been ailing for the last four years and Landsat 5 is older than most slashdotters, though still soldiering on (Landsat 6 was lost on launch.) The delay in launching a continuity mission is a scientific crime, as 35 year's worth of continuous acquisition is going to be interrupted -- unless the ailing birds can keep going to 2011 (+).

There is a gallery of Landsat imagery here.

There are no commercial European satellites with .5 metre pixel capability. The only commercial European Remote Sensing mission currently is SpotImage -- Spot 5 has a 2.5 m capability.

For all those who ask 'how hard can it be?' (shades of Top Gear...) entry level into the commercial Very High Resolution satellite business starts at around half a billion -- don't forget the ground segment. Even future missions are not planning to go much below .4 metre: the problems of handling huge data volumes, programming the satellite acquisitions, and the trade-off in covereage are not worth the gains in sharpness for most commercial users. The US military can get down to about 10 cm (allegedly), but are believed to use highly elliptical orbits (and huge, Hubble-sized telescopes) which would be inmpractical for commercial operators. 10 cm is not as good as Hollywood has got: the last episode of '24' showed what was supposed to be a Landsat image - only it was thermal infrared at about 1 cm updated once a second (as opposed to 15 m every two weeks or more...)

The Man may well have bought 'all the coverage of Afghanistan' -- from a single operator. The Ikonos mission (1m pixel) was the only one operating at the time. The US Govt. does retain 'shutter control' rights of all the VHR missionslicensed by them - which is all the current VHR missions. That will change - especially with COSMO-SkyMed, a constellation of all-weather radar satellites with a max. resolution of >1m, coming soon.

There's a intro to VHR satellite imagery here.

There are no commercial European satellites with .5 metre pixel capability. The only commercial European Remote Sensing mission currently is SpotImage -- Spot 5 has a 2.5 m capability.

For all those who ask 'how hard can it be?' (shades of Top Gear...) entry level into the commercial Very High Resolution satellite business starts at around half a billion -- don't forget the ground segment. Even future missions are not planning to go much below .4 metre: the problems of handling huge data volumes, programming the satellite acquisitions, and the trade-off in covereage are not worth the gains in sharpness for most commercial users. The US military can get down to about 10 cm (allegedly), but are believed to use highly elliptical orbits (and huge, Hubble-sized telescopes) which would be inmpractical for commercial operators. 10 cm is not as good as Hollywood has got: the last episode of '24' showed what was supposed to be a Landsat image - only it was thermal infrared at about 1 cm updated once a second (as opposed to 15 m every two weeks or more...)

The Man may well have bought 'all the coverage of Afghanistan' -- from a single operator. The Ikonos mission (1m pixel) was the only one operating at the time. The US Govt. does retain 'shutter control' rights of all the VHR missionslicensed by them - which is all the current VHR missions. That will change - especially with COSMO-SkyMed, a constellation of all-weather radar satellites with a max. resolution of >1m, coming soon.

There's a intro to VHR satellite imagery here.

Nothing to it - all you need is a 12m tracking dish capable of keeping up with a Low Earth Orbit Satellite on a circa. 90 minute orbit, hardware capable of handling the huge bandwidth required (a single QuickBird scene of about 272 km^2 runs to gigabytes, then you can hack into the satellite to persuade it to unload the raw data from the on-board solid-state memory to your PC which knows how to process it into system-corrected data and then...

look, forget it. Weather satellites are geostationary, and the pictures they send are small. There's a intro to VHR satellite imagery here.

Commerical remote sensing is quite distinct from the kind of Earth Observation TFA is talking about. The commercial business concentrates for the most part on very high resolution imagery, 1 metre pixel size or less -- optical for now, radar too in the near future -- while the kind of science data offered by the Landsat programme, for example, or ESA's ERS/Envisat, has limited commercial value (much of it is available free or at nominal cost to qualified researchers -- or anyone who knows where to look). With Landsat 7 ailing, and Landsat 5 older than most Slashdot contributors, the U.S.'s failure to ensure a Landsat continuity mission after 35 years of uninterrupted data is idiotic, and hopes that this continuity mission can be fobbed off on commercial operators even more so. A useful analogy would be high-energy physics research, or astronomy -- these are pure science and cannot show any immediate commercial return. Meanwhile the Bush administration ties up funds for dumb stunts like the Moon base or a manned mission to Mars, projects with a very poor scientific rationale and such limited feasibility that a non-gambling man like myself would happily bet they will never come to fruition.

You can see much better high-resolution imagery here and here (the images at Eurimage have been sharpened a bit and have better contrast). Don't forget to check out the imagery of Biloxi - which has basically gone the way of Banda Aceh.

You can see much better high-resolution imagery here and here (the images at Eurimage have been sharpened a bit and have better contrast). Don't forget to check out the imagery of Biloxi - which has basically gone the way of Banda Aceh.

Very difficult: DigitalGlobe (then EarthWatch, with EarlyBird), Space Imaging (Ikonos), Orbimage (Orbview) all lost high resolution satellites before they became operational - these early high-res satellites were in fact based pretty much on off-the-shelf (but space qualified) parts. Landsat 6 was lost on launch and Landsat 7 suffered a crippling failure about a year ago. (BTW the EarlyBird launch on a Russian Cosmos, was said to have cost about $7 million, not 50 thousand). Having got it up there, and got it working, you then need a ground segment too, which is decidedly non-trivial.

Here are more images of the destruction in Bam.

The U.S government has always been able to do this with satellites licensed by them - it is called 'shutter control'. In the case of Afghanistan, they preferred to buy the output of Ikonos (the only Very High Resolution satellite then operating) not only to keep it from anyone else but because the data was actually useful - coverage is always a problem with satellite data. Not only that - I think you'll find private companies operating satellites like QuickBird and Ikonos will sell you exclusive rights to imagery if you are willing to pay enough.
You can't keep the imagery from the govt, however. And did you know they will not let those companies sell imagery over Israel or the occupied territories at less than 2 metres resolution, as against the 60 cm capabilities of QuickBird for example.
All this legislation does is prevent using the FoI Act to circumvent restrictions already in place - for US-based companies. And they're not worried about weather sats or Landsat, I'm sure...

Here is a link to some info on that sat.

http://www.eurimage.com/Products/qb.shtml