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Why is the Gaza Strip blurry on Google Maps?

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Re: Why is the Gaza Strip blurry on Google Maps?

#121

Post by Robotbeat »

berkes wrote: post #60
caymanjim wrote: post #34

Earlier quoted context omitted.

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.…

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…

Disagree. The Iridium phone constellation covers the entire planet (which means it has line of sight to the entire planet) and has for about two decades. Starlink will, soon, as well. They’ve already solved the choreography issue you mentioned.

The entire globe has about 500 billion square meters. 24 bit uncompressed imagery is thus 1.5TB per global image. With some modest compression, you could get a video stream of that from the Starlink network, although the current design of Starlink would make it hard to have room for an aperture with better than, say, 3 meter resolution.

Re: Why is the Gaza Strip blurry on Google Maps?

#122

Post by thaumasiotes »

captainmuon wrote: post #115
squeaky-clean wrote: post #97

Not really related to the article at hand, but I've been on a bit of a Google Maps binge the past couple weeks. I learned a few interesting facts, blurry Israel being one of them. Another strange thing I found that might not be super well known (I didn't know about it) is that all GPS data in China is offset by a nonlinear psuedo-random amount. If you turn on the satellite view in Google Maps and look at various citi…

I've found that the maps match the GPS of my phone exactly, but the satellite pictures are shifted. Does that mean: 1) My GPS module also gives out obfuscated coordinates when in China or 2) Google uses shifted satellite images?

> I've found that the maps match the GPS of my phone exactly

I can use OpenStreetMap fine in China. But that's not Chinese data.

If a Chinese person sends me a location marker on WeChat, the marker will show up (for me, in WeChat) at some other, unintended, location; I can't use that feature at all.

Re: Why is the Gaza Strip blurry on Google Maps?

#123

Post by Robotbeat »

recursive wrote: post #92
munk-a wrote: post #79

Earlier quoted context omitted.

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.

> But, we could always ... That's a very bold claim with no support provided.

Should be feasible at very high altitudes where gravity is low.

Re: Why is the Gaza Strip blurry on Google Maps?

#124

Post by squeaky-clean »

captainmuon wrote: post #115
squeaky-clean wrote: post #97

Not really related to the article at hand, but I've been on a bit of a Google Maps binge the past couple weeks. I learned a few interesting facts, blurry Israel being one of them. Another strange thing I found that might not be super well known (I didn't know about it) is that all GPS data in China is offset by a nonlinear psuedo-random amount. If you turn on the satellite view in Google Maps and look at various citi…

I've found that the maps match the GPS of my phone exactly, but the satellite pictures are shifted. Does that mean: 1) My GPS module also gives out obfuscated coordinates when in China or 2) Google uses shifted satellite images?

I wish I had saved some of the links I had found, one source I read said that the non-satellite map data was actually correct, and it was the stitching of the satellite imagery that was incorrect. I had no way to test this and no other source mentioned this, so I ignored it. But it's funny you mention this, #2 might be the case.

robotastronaut also corrected me that it's not actually the GPS that is being obfuscated, but the map coordinate system. So your GPS device is probably receiving correct results, but on an improperly projected map.

Re: Why is the Gaza Strip blurry on Google Maps?

#125

Post by [deleted] »

caymanjim wrote: post #34
deadalus wrote: post #5

Is it possible to have real-time live-feed of the entire planet? If cost isn't an issue, would something like that be possible?

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.…

[deleted]

Re: Why is the Gaza Strip blurry on Google Maps?

#126

Post by manquer »

There is perhaps an interesting machine learning application here.

There are higher resolution images available at lower frequencies and low resolution images possible with high frequency.

Would it not possible to "zoom and enhance" a low resolution image to higher resolution one using historical high res data of the location and learning from object types and classification?

Re: Why is the Gaza Strip blurry on Google Maps?

#127

Post by Sebb767 »

recursive wrote: post #92
munk-a wrote: post #79

Earlier quoted context omitted.

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.

> But, we could always ... That's a very bold claim with no support provided.

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 ;)

Re: Why is the Gaza Strip blurry on Google Maps?

#128

Post by dirtyid »

squeaky-clean wrote: post #97

Not really related to the article at hand, but I've been on a bit of a Google Maps binge the past couple weeks. I learned a few interesting facts, blurry Israel being one of them. Another strange thing I found that might not be super well known (I didn't know about it) is that all GPS data in China is offset by a nonlinear psuedo-random amount. If you turn on the satellite view in Google Maps and look at various citi…

Have you checked out South Korea?

Re: Why is the Gaza Strip blurry on Google Maps?

#129

Post by johnmcelhone »

rsync wrote: post #57
mvanaltvorst wrote: post #43

Earlier quoted context omitted.

planet.com can get you a ~12 images per day [1] for a reasonable price. If cost really isn't an issue, I'm confident you could strike a deal with planet.com to place their next few new satellites into the specific orbit you want to up the frequency even more. [1]: https://www.planet.com/pulse/12x-rapid-revisit-announcement/ , as of June 2020.

What is that reasonable price? It is not given on the page you linked…

I believe 3m res data from them is around the $2 per square kilometre mark, however varies wildly depending on scale
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