After a quick search, I found a few videos which showed scenes of an area with some traffic activity but it wasn't that zoomed in. As far as images go, I haven't found any other image source providing a better definition image than what Google Maps provide.
The American government had used live satellite feed while carrying out the Bin Laden operation ( Source of Information: Documentary | Correct me if wrong ).
Are there any images/videos publicly available which demonstrate the limits of cameras in space directed towards earth ?
If not publicly available, can you describe how a possible image/video might look like and what are the current limits for those cameras ?
I'm pretty sure that the satellites at the time could read 3 inch newspaper print under the right conditions which happened rarely.
I've got a tack sharp 600mm Canon lens and it's sort of useless for a lot of stuff. If there is any haze, heat, dust, whatever, in the air, all that expense glass sees is that instead of what you want to see.
That note aside, it was a fun project. I was the I/O guy, I did this work:
http://www.nfsv4bat.org/Documents/ConnectAThon/1996/bds.pdf
and I got Seagate to redesign part of their 9gb (I think, might have been 2 or 4g) barracudas. I've got a benchmark in lmbench that shows how the disk performs as a function of seek distance, looks like this:
http://mcvoy.com/lm/bitmover/disks/seek.gif
The lower edge of the band is what you get if you seek and get to the track just as the sector you want is to about to pass under the head; the upper edge of the band is what you get if the sector had just passed under the head; the height of the band is a rotational delay; and those outliers? In this case I think they were either bad blocks or I don't know.
But when you ran this benchmark on two drives, mounted in a rack right next to each other, you got tons and tons of outliers which blew any chance we had of meeting the performance metrics. I bitched at Seagate and they hemmed and hawed and finally admitted there might be a problem with their internal mounts.
The problem was that their mounts were so useless that the vibration caused by one head moving vibrated the drive next to it enough that the other drive's head didn't settle properly and you blew a rev waiting for it to get where it needed to be.
Seagate redid the mounts.
Fun project.
Now thinking about it, it might've been a high-altitude plane (U2) photo instead, but I'm not sure.
Has anyone else seen this photo?
Also looking right from the top, at the best conditions, from 200km (a stable orbit can't be lower), will give 4cm resolution for a Hubble-like mirror, or 2cm per pixel Niquist frequency.
And now they are happy because RAID configurations are fairly common these days.
But more resolution isn't what's important. Other capabilities, such as deep infrared, ultraviolet, radio, whatever scanning is more useful. Sats made U-2s, SR-71s mostly obsolete; drones are doing a lot of what Sats did. Top of the list though is refueling spy sats. That is the Holy Grail of reconnaisance which the USAF X-37B totally experimental research craft totally doesn't do.
Refueling massively extends their use and lifespan. Its like have twice as many for the money. Cuz, ya know, a hundred ain't enough.
They have onboard fuel for "stationkeeping"; most low orbit sats do. That is keeping them in their proper orbit and attitude in spite of drag.
https://en.wikipedia.org/wiki/GeoEye-1
31cm/pixel through WorldView-4
> "The latest US spy satellites, in comparison, are reported to be able to pick out objects less than 10cm (4 inches) across."
http://www.bbc.com/future/story/20140211-inside-the-google-e...
https://space.stackexchange.com/questions/3868/is-photograph...
http://boards.straightdope.com/sdmb/showthread.php?t=627617
https://everything2.com/title/Spy+satellites+can%2527t+read+...
A perfect 2.4-meter mirror observing in the visual (500 nm) would have a diffraction limited resolution of around 0.05 arcsec, which from an orbital altitude of 250 km would correspond to a ground sample distance of 0.05 m. Operational resolution should be worse due to effects of the atmospheric turbulence.
As an aside, that donation has actually put NASA in a bit of a bind. For political reasons they can't very well turn down the offer. But the telescope itself is only about one third of the total cost of space telescope, with the rest being due to the cost of the instruments and the launch itself. Unlike the US military, NASA does not have an unlimited budget so this unexpected expense threw a wrench into their long-term plans. Furthermore, the telescopes were designed to look down instead of up, so they're not optimized for astronomical observations.
http://www.space.com/16077-nasa-space-telescopes-failed-nro-program.html
That said, I don't think they'll give an appreciably better resolution -- given good fabrication techniques, optically a 2.4m mirror is a 2.4m mirror, and everything I've read suggests that US IMINT satellites have been (in good seeing conditions) close to diffraction-limited for a long time now.
I'm sure the capabilities of the satellites have improved a great deal, but in other directions than resolution. More communications bandwidth? Faster repointing (giving more flexibility about which targets get imaged on a given pass? Better multi-spectral imaging? I'm sure there will be some surprises when the program is eventually declassified. (And I'm optimistic it will be -- there's lots you can read now about the film-return satellites).
Disclaimer: I'm the OP on that question.
Satellite cameras don’t have a 2D sensor you can find in a traditional camera. Instead, they feature a long narrow sensor. As the satellite flies over the earth, the sensor records a single row below the satellite. That row is oriented perpendicular to the satellite’s velocity. As the satellite flies, it scans a long strip of land underneath.
It works similar to a flatbed scanner. Can you film a video with the scanner? I don’t think so.
https://en.wikipedia.org/wiki/Push_broom_scanner
About Bin Laden, the live satellite feed was not filmed from space. The feed was recorded by an on-body camera of an American soldier, transferred to a telecom satellite, then back to Earth, at Obama’s place.
https://terrabella.google.com/
The ground wind speed at the time of eruption was below 5 m/s, i.e. the video plays much faster then real-time.
If you’ll download the video, pause it, skip between frames, you’ll notice different parts were shot from different positions and with different resolutions.
They probably abused the fact clouds move in very predictable manner. They took several satellite images from whatever satellites happen to pass roughly above the volcano, and used creative video editing to make a smooth video from those several frames.
https://www.wired.com/2011/05/with-drones-and-satellites-u-s...
This article explains more about how they used a combination of satellite imagery and drones.
I recall reading somewhere about satellites being able to see license plate numbers from space but I have no idea where I read that or if it's true.
even the supposedly recorded-with-mobile footage is always so bad. as if the person is stumbling around not knowing their phone's cammera is rolling.
I'd also suspect anyone recording a news-worthy "incident" on their mobile phone in a war zone has other priorities than maintaining a stable image.
Hard to say what you're talking about without examples, but stuff like military targeting cameras are frequently 1970s tech, and looking via infrared to boot. There's plenty of high-res footage from war zones available.
> even the supposedly recorded-with-mobile footage is always so bad. as if the person is stumbling around not knowing their phone's cammera is rolling.
Being shot at has that sort of effect. That said, there's some pretty remarkable 4k drone footage coming out of ISIS these days, along with lots of GoPro footage.
As many have alluded to here, there's likely to be a big difference between publicly available imagery and what's currently possible. Sticking to publicly available stuff though, while the resolution of all mapping services varies a lot across the globe, http://wego.here.com provides satellite imagery that betters Google's in a lot of cases.
This is all somewhat moot if you're looking for MIB-esque video of course as these still images are compiled rather than directly snapshotted
For example http://www.cropcopter.co/uav-imagery-vs-satellite/
Those are precisely the reasons satellites will remain relevant. Satellites are the reason the SR-71 fell out of service. Russia can and will shoot down US aircraft or drones in their airspace.
For the full NIIRS rating: https://fas.org/irp/imint/niirs.htm