What are these things in China's desert

[Mangetout]

@Filbert

If they’re using an automatic adjustment, you’d expect the same effect to show up elsewhere, and if this was, for some odd reason, done by hand, it seems a bit strange that anyone would leave it like that. Plus there’s another ‘runway’ just a little to the west and with no photo edge lines in between, which appears a very deep shade of blue. It looks to me like it’s a reflective surface, reflecting sky. Same goes for the roofs of the buildings nearby- which are deep blue in that photo.

Lots of things in that photo seem bluer than they ought to be - including some non-reflective bits of dark terrain. Thats why I think the colours have been adjusted for some other reference point. Same thing appears in parts of Libya on Google Maps.

[kenobi_65]

According to a new article on Space.com, a research technician at Arizona State, who works on imaging projects for NASA, believes that they are very likely calibration targets for Chinese spy satellites.

[jjimm]

@Mangetout

Sure - I’ve seen flooded clay pits where the water was absurdly blue due to minerals (or possibly colloids)

OT, but just out of interest here is a picture I took of a very blue lake in Tibet (Yamdrok-Tso), but here is a picture I took of the most ridiculous, child’s coloring book-style cyan lake in New Zealand (Lake Tekapo - pic not retouched in any way). The reason for both lakes’ color is ‘glacial flour’.

[nutrition]

this is really awsome, don’t know what these chinese have been doing.

[Mangetout]

If you zoom out, you can see where the blue cast isn’t natural . Here’s a link that shows one of the boundaries :

[Spoke]

@Spezza

Missile testing, at least the grid ones. For sophisticated guide missiles, the grid patterns resemble a city layout and can be used to testing.

The one with concentric circle looks very much like the solar plant built in Spain.

Yeah, I was going to guess bombing range targets.

@kenobi_65

According to a new article on Space.com, a research technician at Arizona State, who works on imaging projects for NASA, believes that they are very likely calibration targets for Chinese spy satellites.

That makes sense.

[Brown_Eyed_Girl]

@Mangetout

If you zoom out, you can see where the blue cast isn’t natural . Here’s a link that shows one of the boundaries :
Google Maps

Seems to me that the seam you’re referencing is where two images were stitched together and that they may have been taken at different times of day. If the sun were in a different position in both images, there very well could be a natural blue hue cast due to the filtering of yellow and red light by the atmosphere.

[Mangetout]

I’m sure the images were taken at different times and stitched together - and it’s possible the colour cast is entirely natural, but as it’s all sorts of things that are blue - including rocks and soil (that probably shouldn’t really appear blue even if illuminated by blue light), I believe a more likely explanation is that the images have been adjusted by attenuating the level of red in them, for some reason.

[Mangetout]

…Either way, I don’t believe the objects on the ground are as physically blue as they appear in those images

[jjimm]

I still think they’re reflecting the sky. At other altitudes where the sky is hazy, they appear light gray.

[Fiendish_Astronaut]

Here’s the UKs Guardian article on all this: Mystery of unidentified Chinese desert patterns solved ... mostly | Environment | The Guardian