7 ms·

The short answer is no. High-resolution imagery comes from low-orbit satellites, which make a complete orbit about every two hours, and image long, narrow strip

The short answer is no. High-resolution imagery comes from low-orbit satellites, which make a complete orbit about every two hours, and image long, narrow strips with each pass, taking days to image the whole planet. There are many of these satellites: commercial, non-military (publicly-accessible) governmental, and governmental (secret), of varying resolutions. These are also supplemented by aerial (plane) imagery. The net result is that updated-daily imagery exists, but real-time does not. While I'm not privy to the capabilities of the US military, the kind of real-time planet-wide surveillance that movies like Enemy of the State suggest doesn't exist planet-wide. The highest-resolution images on e.g. Google Maps are from planes, rather than satellites, and aren't imaged anywhere near daily. The only way to have constant, real-time imaging of a fixed location is with a geostationary satellite, which will be so far away (22,000 miles) that the resolution will be low. Given an unlimited budget, a huge constellation of hundreds or thousands of satellites could come close to real-time planet-wide imaging, but even then, you'd be getting views at different angles as various satellites took images, and you wouldn't ever have a clear directly-overhead view of people walking around.

notJim 5y ago
Couldn't starlink do something like this theoretically? Seems like it checks several of the boxes.
- deleted 5y ago
  [deleted]
manigandham 5y ago
A fleet of drones that stay airborne can provide real-time feeds of a regional battlespace for military use. Cheaper, lower latency, higher quality data - but vulnerable to enemy airpower.
therein 5y ago
Even though it would be neither covert nor cost-effective, couldn't you use a constellation like Iridium and add some auto-compositing capabilities? The resolution and angles for your point of interest will change but you should be able to keep a near-constant coverage.
berkes 5y ago
And even with such a budget: geostationary satellites over the poles are not possible[1] and really hard anywhere but over the equator, really. So that means most of the south and north part of the earth cannot be covered with such a constellation; they would need to be orbiting satellites, which makes "real time" even harder, because it would require an enormously complex choreography to ensure there's at least one satellite covering each square meter, at all times. [1] https://physics.stackexchange.com/questions/71582/is-it-possible-to-have-a-geostationary-satellite-over-the-poles https://physics.stackexchange.com/questions/71582/is-it-poss...
- munk-a 5y ago
  But, we could always construct a dyson sphere around earth and rely on the rigidity of the structure to provide accurate polar images. That said, it would be really difficult and quite likely not at all worth it.
  - recursive 5y ago
    > But, we could always ... That's a very bold claim with no support provided.
    - Robotbeat 5y ago
      Should be feasible at very high altitudes where gravity is low.
      - recursive 5y ago
        On the other hand, I think it should not be feasible. How many kilograms of raw materials would be required? And at what altitude? I don't think there's enough propellant on earth to lift that much stuff.
    - Sebb767 5y ago
      Pun aside, this is the more in the realm of "theoretically possible" rather than possible right now. And people don't consider sun-sized Dyson spheres impossible, so a planet-sized one should be a piece of cake. Though the live imagery would now need night vision cameras, as we blocked out all our light with our camera support. But one has to take the good with the bad ;)
cryptoz 5y ago
It seems like the answer is actually yes, then? Seems like it would be expensive but that is no issue with this thought experiment. OP didn't require High-res or directly-overhead, some caveats you added which constrain the problem more. But either way, it totally seems possible. Heck, put up 100,000 satellites and use the same kind of tech Apple/Google/MS use in their 3D views of cities (it, they do take airplane and satellite photos at various angles, and use software to stitch together the separate pieces). Seems totally possible to meet OP's request given money not being an issue.
panarky 5y ago
Starlink is seeking approval for tens of thousands of low-earth-orbit satellites. Each one will have high-bandwidth network connections. It doesn't seem intractable to put cameras on each one and stitch their feeds together for imagery that's maximum 30 minutes old for any arbitrary point on the globe. And the market for near-real-time imagery might be even larger than the market for internet connectivity.
- adolph 5y ago
  The next generation of LEO ground imaging satellites will be significantly larger than Starlink units. Now, with the resolution relaxation from the United States Government that went into effect on February 21, 2015, you have access to an even clearer view of the ground with 30-centimeter resolution commercial satellite imagery. https://spacenews.com/a-detailed-view-of-the-ground-with-30-centimeter-satellite-imagery/ https://spacenews.com/a-detailed-view-of-the-ground-with-30-... WorldView-3 is the industry’s first multi-payload, super-spectral, highresolution commercial satellite. Operating at an altitude of 617 km, WorldView-3 provides 31 cm panchromatic resolution, 1.24 m multispectral resolution, 3.7 m short-wave infrared resolution, and 30 m CAVIS resolution. WorldView-3 has an average revisit time of less than one day and is capable of collecting up to 680,000 sq km per day, further enhancing the Maxar collection capacity for more rapid and reliable collection. https://www.maxar.com/constellation https://www.maxar.com/constellation WorldView-3: Mass: 2800 kg (6200 lbs) Power: 3.1 kW solar array, Altitude: 617 km Starlink: Mass: v 1.0: 260 kg (573 lb) Power: 6 kW solar array, Altitude: 550 km https://lilibots.blogspot.com/2020/04/starlink-satellite-dimension-estimates.html https://lilibots.blogspot.com/2020/04/starlink-satellite-dim... https://en.wikipedia.org/wiki/Starlink#Constellation_design_and_status https://en.wikipedia.org/wiki/Starlink#Constellation_design_...
  - deleted 5y ago
    [deleted]
- redfern314 5y ago
  This is more or less the business model of Planet [0], which is imaging the whole Earth every day with around 200 satellites. (No affiliation, but I previously worked for a different smallsat company.) It would be possible to get a higher visitation than that with more satellites, but it may not be cost-effective (e.g. someone might be willing to pay $X for a subscription to daily images, but not $(48*X) for half-hour images). I also doubt you could just slap a camera on Starlink satellites. Even ignoring payload size/weight, power consumption, etc, you're typically fighting 3 different constraints when you decide which way to rotate your satellite (sun exposure for power, antenna direction for high-bandwidth network, payload direction if you have cameras or other directional sensors). They're not going to want to try to deal with that for the first iteration of their fleet. [0] https://www.planet.com/products/planet-imagery/ https://www.planet.com/products/planet-imagery/
yabones 5y ago
There are also surveillance blimps, which I believe would be closest to a real-time feed. Some can apparently stay up for 30 days at a time. These have been tested for domestic intelligence, and radar (rather than optical) systems have been deployed overseas. https://www.washingtonpost.com/business/technology/blimplike-surveillance-crafts-set-to-deploy-over-maryland-heighten-privacy-concerns/2014/01/22/71a48796-7ca1-11e3-95c6-0a7aa80874bc_story.html https://www.washingtonpost.com/business/technology/blimplike... https://en.wikipedia.org/wiki/Tethered_Aerostat_Radar_System https://en.wikipedia.org/wiki/Tethered_Aerostat_Radar_System
Macuyiko 5y ago
Since you know what you're talking about. Say I'm willing to accept the updated-daily or even weekly high-res imagery of the whole planet. Any idea what the cost would boil down to? How many parties are involved? Just wanting to learn more about this.
- s0rce 5y ago
  Sentinel imagery is weekly and is quite good. I use it to see snow melting in the mountains when planning hikes.
- Robotbeat 5y ago
  There’s a company called PlanetLabs (or just Planet) which aspires to this.
- johnmcelhone 5y ago
  Want medium res (10m), Sentinel-2 imagery is your best bet. Won't cost you a penny. https://apps.sentinel-hub.com/eo-browser/ https://apps.sentinel-hub.com/eo-browser/ Looking for higher resolution (3m), the only viable option really is Planet. Even at that, they're pretty iffy with their pricing models and distribution. I think they range around the $2 per square kilometre mark.
  - dragonwriter 5y ago
    for the whole planet, the jump between $0 and around $2/sq.km. is, what, $1 billion/update difference?
- CallMeMarc 5y ago
  I'm no expert but there was an Ask HN about new APIs[1] recently. One answer linked to Albedo[2] which seems quite interesting. [1] https://news.ycombinator.com/item?id=27067945 https://news.ycombinator.com/item?id=27067945 [2] https://www.albedo.space/ https://www.albedo.space/
throwaway894345 5y ago
What limits the field of view of these LEO satellites? Why can we not have high resolution images of wider swaths? Is it something like the number of "receptors" on an imaging cell, or would wider angle lenses significantly distort the imagery?
- Rebelgecko 5y ago
  The curvature of the earth is gonna be a limiting factor for satellites in LEO. IIRC at 500 miles up you can only see (roughly) 1500 miles away. And realistically your range will be less than that because something that far away will be at a very oblique angle, which means more atmosphere in the way and more distortion
deleted 5y ago
[deleted]
7952 5y ago
Obviously different to optical images. But I wonder if this kind of live view would be more possible with SAR at higher orbits. And with enough signal processing may actually be more useful for automated analysis than cloudy images.
csteubs 5y ago
I'm the founder of a company working to solve this exact problem. Revisit rate of Planet's 200+ Dove satellites are quite good (multiple/day) but are comparatively low-res compared to their Rapideye satellites, of which there are fewer. There are a slew of others (Maxar is the next biggest name that comes to mind) but the thesis is low earth orbit is getting crowded, satellites are incredibly expensive even with off-the-shelf parts and falling launch costs, and hardware capabilities are locked-in at launch. We're taking the approach of using "free energy" in the form of 100,000+ daily commercial/freight/general aviation aircraft to crowdsource aerial imagery using mobile phones to start. Passengers who opt-in are rewarded with free in-flight wifi (where equipped), and we use the device to do orthorectification and photogrammetry at the edge before transmitting it back down via satellite internet. I'm glossing over much of the actual process, but this frees up a ton of computing that would otherwise have to be done on the ground. In the event the flight is not internet connected, we cache previous images based on flight path and upload the difference after comparing old vs. new on the device once signal is restored. End result is a massive boost in both temporal and spatial resolution at a dramatically lower cost. Think Google Maps, updated every few minutes. We're on IG @notasatellite if you're interested in looking at some samples.
- newman8r 5y ago
  Are you talking about passengers taking photos/video out of windows?
  - csteubs 5y ago
    Correct. It sounds a bit far-out (and it is) but we've proven the feasibility with a testing group of around 300 passengers using a multitude of different phones/altitudes/conditions/routes. GPS works in airplane mode, so we pre-cache target coordinates based on the filed flight plan and alert the passenger to hold the device to the window when overflying the target. The gyroscope is used to provide feedback on phone orientation so we can get as close to nadir as possible, but we're still able to correct for obliques at around 20miles on the horizon using some general inference. Resolution is a function of altitude and device, but upscaling techniques enhance the images even further after they're transmitted. We've also developed our own sensing device prototype we call "The Box" that's equipped with a much more powerful array of sensors, but the mobile device-sensing approach makes the most sense for a scalable MVP.

notJim 5y ago

Couldn't starlink do something like this theoretically? Seems like it checks several of the boxes.

deleted 5y ago
[deleted]

manigandham 5y ago

A fleet of drones that stay airborne can provide real-time feeds of a regional battlespace for military use. Cheaper, lower latency, higher quality data - but vulnerable to enemy airpower.

therein 5y ago

Even though it would be neither covert nor cost-effective, couldn't you use a constellation like Iridium and add some auto-compositing capabilities? The resolution and angles for your point of interest will change but you should be able to keep a near-constant coverage.

berkes 5y ago

And even with such a budget: geostationary satellites over the poles are not possible[1] and really hard anywhere but over the equator, really. So that means most of the south and north part of the earth cannot be covered with such a constellation; they would need to be orbiting satellites, which makes "real time" even harder, because it would require an enormously complex choreography to ensure there's at least one satellite covering each square meter, at all times. [1] https://physics.stackexchange.com/questions/71582/is-it-possible-to-have-a-geostationary-satellite-over-the-poles https://physics.stackexchange.com/questions/71582/is-it-poss...

munk-a 5y ago
But, we could always construct a dyson sphere around earth and rely on the rigidity of the structure to provide accurate polar images. That said, it would be really difficult and quite likely not at all worth it.
- recursive 5y ago
  > But, we could always ... That's a very bold claim with no support provided.
  - Robotbeat 5y ago
    Should be feasible at very high altitudes where gravity is low.
    - recursive 5y ago
      On the other hand, I think it should not be feasible. How many kilograms of raw materials would be required? And at what altitude? I don't think there's enough propellant on earth to lift that much stuff.
  - Sebb767 5y ago
    Pun aside, this is the more in the realm of "theoretically possible" rather than possible right now. And people don't consider sun-sized Dyson spheres impossible, so a planet-sized one should be a piece of cake. Though the live imagery would now need night vision cameras, as we blocked out all our light with our camera support. But one has to take the good with the bad ;)

cryptoz 5y ago

It seems like the answer is actually yes, then? Seems like it would be expensive but that is no issue with this thought experiment. OP didn't require High-res or directly-overhead, some caveats you added which constrain the problem more. But either way, it totally seems possible. Heck, put up 100,000 satellites and use the same kind of tech Apple/Google/MS use in their 3D views of cities (it, they do take airplane and satellite photos at various angles, and use software to stitch together the separate pieces). Seems totally possible to meet OP's request given money not being an issue.

panarky 5y ago

Starlink is seeking approval for tens of thousands of low-earth-orbit satellites. Each one will have high-bandwidth network connections. It doesn't seem intractable to put cameras on each one and stitch their feeds together for imagery that's maximum 30 minutes old for any arbitrary point on the globe. And the market for near-real-time imagery might be even larger than the market for internet connectivity.

adolph 5y ago
The next generation of LEO ground imaging satellites will be significantly larger than Starlink units. Now, with the resolution relaxation from the United States Government that went into effect on February 21, 2015, you have access to an even clearer view of the ground with 30-centimeter resolution commercial satellite imagery. https://spacenews.com/a-detailed-view-of-the-ground-with-30-centimeter-satellite-imagery/ https://spacenews.com/a-detailed-view-of-the-ground-with-30-... WorldView-3 is the industry’s first multi-payload, super-spectral, highresolution commercial satellite. Operating at an altitude of 617 km, WorldView-3 provides 31 cm panchromatic resolution, 1.24 m multispectral resolution, 3.7 m short-wave infrared resolution, and 30 m CAVIS resolution. WorldView-3 has an average revisit time of less than one day and is capable of collecting up to 680,000 sq km per day, further enhancing the Maxar collection capacity for more rapid and reliable collection. https://www.maxar.com/constellation https://www.maxar.com/constellation WorldView-3: Mass: 2800 kg (6200 lbs) Power: 3.1 kW solar array, Altitude: 617 km Starlink: Mass: v 1.0: 260 kg (573 lb) Power: 6 kW solar array, Altitude: 550 km https://lilibots.blogspot.com/2020/04/starlink-satellite-dimension-estimates.html https://lilibots.blogspot.com/2020/04/starlink-satellite-dim... https://en.wikipedia.org/wiki/Starlink#Constellation_design_and_status https://en.wikipedia.org/wiki/Starlink#Constellation_design_...
- deleted 5y ago
  [deleted]
redfern314 5y ago
This is more or less the business model of Planet [0], which is imaging the whole Earth every day with around 200 satellites. (No affiliation, but I previously worked for a different smallsat company.) It would be possible to get a higher visitation than that with more satellites, but it may not be cost-effective (e.g. someone might be willing to pay $X for a subscription to daily images, but not $(48*X) for half-hour images). I also doubt you could just slap a camera on Starlink satellites. Even ignoring payload size/weight, power consumption, etc, you're typically fighting 3 different constraints when you decide which way to rotate your satellite (sun exposure for power, antenna direction for high-bandwidth network, payload direction if you have cameras or other directional sensors). They're not going to want to try to deal with that for the first iteration of their fleet. [0] https://www.planet.com/products/planet-imagery/ https://www.planet.com/products/planet-imagery/

yabones 5y ago

There are also surveillance blimps, which I believe would be closest to a real-time feed. Some can apparently stay up for 30 days at a time. These have been tested for domestic intelligence, and radar (rather than optical) systems have been deployed overseas. https://www.washingtonpost.com/business/technology/blimplike-surveillance-crafts-set-to-deploy-over-maryland-heighten-privacy-concerns/2014/01/22/71a48796-7ca1-11e3-95c6-0a7aa80874bc_story.html https://www.washingtonpost.com/business/technology/blimplike... https://en.wikipedia.org/wiki/Tethered_Aerostat_Radar_System https://en.wikipedia.org/wiki/Tethered_Aerostat_Radar_System

Macuyiko 5y ago

Since you know what you're talking about. Say I'm willing to accept the updated-daily or even weekly high-res imagery of the whole planet. Any idea what the cost would boil down to? How many parties are involved? Just wanting to learn more about this.

s0rce 5y ago
Sentinel imagery is weekly and is quite good. I use it to see snow melting in the mountains when planning hikes.
Robotbeat 5y ago
There’s a company called PlanetLabs (or just Planet) which aspires to this.
johnmcelhone 5y ago
Want medium res (10m), Sentinel-2 imagery is your best bet. Won't cost you a penny. https://apps.sentinel-hub.com/eo-browser/ https://apps.sentinel-hub.com/eo-browser/ Looking for higher resolution (3m), the only viable option really is Planet. Even at that, they're pretty iffy with their pricing models and distribution. I think they range around the $2 per square kilometre mark.
- dragonwriter 5y ago
  for the whole planet, the jump between $0 and around $2/sq.km. is, what, $1 billion/update difference?
CallMeMarc 5y ago
I'm no expert but there was an Ask HN about new APIs[1] recently. One answer linked to Albedo[2] which seems quite interesting. [1] https://news.ycombinator.com/item?id=27067945 https://news.ycombinator.com/item?id=27067945 [2] https://www.albedo.space/ https://www.albedo.space/

throwaway894345 5y ago

What limits the field of view of these LEO satellites? Why can we not have high resolution images of wider swaths? Is it something like the number of "receptors" on an imaging cell, or would wider angle lenses significantly distort the imagery?

Rebelgecko 5y ago
The curvature of the earth is gonna be a limiting factor for satellites in LEO. IIRC at 500 miles up you can only see (roughly) 1500 miles away. And realistically your range will be less than that because something that far away will be at a very oblique angle, which means more atmosphere in the way and more distortion

deleted 5y ago

[deleted]

7952 5y ago

Obviously different to optical images. But I wonder if this kind of live view would be more possible with SAR at higher orbits. And with enough signal processing may actually be more useful for automated analysis than cloudy images.

csteubs 5y ago

I'm the founder of a company working to solve this exact problem. Revisit rate of Planet's 200+ Dove satellites are quite good (multiple/day) but are comparatively low-res compared to their Rapideye satellites, of which there are fewer. There are a slew of others (Maxar is the next biggest name that comes to mind) but the thesis is low earth orbit is getting crowded, satellites are incredibly expensive even with off-the-shelf parts and falling launch costs, and hardware capabilities are locked-in at launch. We're taking the approach of using "free energy" in the form of 100,000+ daily commercial/freight/general aviation aircraft to crowdsource aerial imagery using mobile phones to start. Passengers who opt-in are rewarded with free in-flight wifi (where equipped), and we use the device to do orthorectification and photogrammetry at the edge before transmitting it back down via satellite internet. I'm glossing over much of the actual process, but this frees up a ton of computing that would otherwise have to be done on the ground. In the event the flight is not internet connected, we cache previous images based on flight path and upload the difference after comparing old vs. new on the device once signal is restored. End result is a massive boost in both temporal and spatial resolution at a dramatically lower cost. Think Google Maps, updated every few minutes. We're on IG @notasatellite if you're interested in looking at some samples.

newman8r 5y ago
Are you talking about passengers taking photos/video out of windows?
- csteubs 5y ago
  Correct. It sounds a bit far-out (and it is) but we've proven the feasibility with a testing group of around 300 passengers using a multitude of different phones/altitudes/conditions/routes. GPS works in airplane mode, so we pre-cache target coordinates based on the filed flight plan and alert the passenger to hold the device to the window when overflying the target. The gyroscope is used to provide feedback on phone orientation so we can get as close to nadir as possible, but we're still able to correct for obliques at around 20miles on the horizon using some general inference. Resolution is a function of altitude and device, but upscaling techniques enhance the images even further after they're transmitted. We've also developed our own sensing device prototype we call "The Box" that's equipped with a much more powerful array of sensors, but the mobile device-sensing approach makes the most sense for a scalable MVP.