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abcd_f

Doesn't appear on the satellite view in Google Maps. Just water.

What's up with that?

https://maps.app.goo.gl/dr71WrLZ7G97E5br9?g_st=ic

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The issue of how the satellite data feed ends up censored is pretty interesting. Here's the probable central issue:

> "While countries still reserve the right to withhold map data, the number of state and private companies that sell satellite images makes hiding the globe incredibly difficult. At the same time, this also means that state or non-state actors can beat private companies to the exclusive rights of a satellite image, meaning they can partially censor the image before others can license it."

https://www.abc.net.au/news/2019-02-21/why-large-parts-of-ea...

There's historical imaging on Google Earth https://earth.google.com/web/@40.24978465,50.87045099,-66.75...

Weirdly time lapse mode has a clearer image of it.

Interesting. It's not just the oil rig itself, the whole lake's satellite view is the same blue colour, while other bodies of water are more detailed.

Oceans, plus I guess the Caspian Sea, don’t get much satellite coverage because no one (except militaries) wants it enough. For the ocean, Google Maps uses bathymetry data to synthesise shaded blue imagery. The Caspian in particular I guess is such a uniform colour either because it’s so shallow that Google’s shading algorithm doesn’t shade it at all? (Compare to the northwesternmost parts of the Adriatic Sea, for example)

A big issue here too is the image stitching; aerial images are registered for big tile maps based in part on feature analysis of the edges and that just never works right for images of the ocean (mostly you have waves, and they're in different places in each image). Even if you register it perfectly the waves ensure that the edges will still have stitching artifacts. As a result the "false color" oceans that Google Maps shows just look better than actual imagery.

The "imagery" source for the oceans in Google Maps is (or at least was) GEBCO, it's a global bathymetric dataset made by registering depth sounding tracks from mostly commercial vessels. I thought maybe GEBCO didn't cover the caspian sea but it looks like it does for the last decade or so, but admittedly it seems to be data from just one survey and it's tagged as limited quality (at least in older versions of the dataset), so maybe Google ignores it.

Products like Google Maps stitch satellite and aerial photos together to make a cohesive image.

There's no reason to spend tens of thousands of dollars on getting precise images in the middle of a sea or ocean from Maxar so a low-res image is more than enough.

Also, most of the high-res images you see of regions on Google Earth or Maps tends to come from aerial photography, not satellites.

These products will also update the images every couple months to years. For example, you could see the aftermath of the Donetsk airport battle and Homs Siege in Google Maps in 2014-15, but not anymore.

It’s not a low-res image… because the oil rig city would still be blurry but somewhat visible, it’s a no-res image, entirely generated with no connection to reality.

Google Maps' satellite photography only extends a bit into seas, where it transitions to bathymetric data. It looks like the Caspian Sea doesn't have any bathymetric data though, which is strange. Even the great lakes have it.

Copernicus covers it:

https://browser.dataspace.copernicus.eu/?zoom=13&lat=40.2387...

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