With detailed satellite imagery, why can’t we see garbage in the oceans on digital maps or on Google Earth?

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With detailed satellite imagery, why can’t we see garbage in the oceans on digital maps or on Google Earth?

In: Technology

Most garbage is very, very small, and the Earth is very, very big. Google Maps is detailed, but not that detailed.

In general Google does not buy satellite imagery of the oceans. What you see is very low resolution imagery taken from public sources. They do not show any smaller garbage as they are intended to photograph the weather and may even have a hard time seeing ships. The plastic in the ocean is quite small pieces, think shopping bags and plastic bottles. And although it is a lot of trash it is spread over huge areas. You do not get many clumps of plastic in the ocean but rather huge patches the sizes of continents with a very dispersed amount of plastic in it.

Because movies have lied to you

Most satellite imagery is around 0.5-1 meter/pixel. GeoEye-1 is one of the better commercial satellites at 0.41 meters/pixel, a Keyhole-11 era spy satellite with its 2.4 meter mirror might pull off 0.1 meters/pixel

That’s enough to see that there is a person somewhere, but not enough to see who it is.

With the 0.5 meter resolution images you’re seeing on Google you might see a difference in the color of the ocean where the garbage patch is but you certainly won’t see individual pieces of trash and the computer likely sorts it out. Google wants to give good imagery so the computers run through images and try to pick ones without clouds/planes/debris. And particularly for the deep ocean they tend to just replace it with a nice smooth texture because there’s no real info to be had more than a few miles from shore so they don’t need to store terabytes of additional useless data.