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Comment by hmokiguess | Hacker News Reader

Tangential comment but I still don't understand how we have technology to identify a car license plate from space but we have pixelated images from Antarctica on Google Maps / Google Earth. Why not publish that and make it accessible? Is it true that Antarctica is not easy to scan due to ice and snow?

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Not sure this is the reason but: it is generally not easy to get a satellite over the poles. You launch close to the equator in the direction of Earth's spin to take advantage of the (very substantial!) speed you already have due to the rotation of the planet. Getting from an equatorial orbit to a polar one requires a huge amount of fuel / energy. You can't just sort of "drive it over".

Source: played a bunch of Kerbal space program

There’s enough satellites in Sun-synchronous orbit (97-ish degree inclination) that polar coverage should be pretty good by now, I’d imagine. The gap from the big guns (GEO and MEO) is more than made up by LEO.

Google Maps' high-resolution "satellite" imagery is actually captured from planes.

Antarctica is huge (1.5x the area of the US), it would be a dangerous logistical nightmare to fly the sorts of patterns you need to capture aerial imagery there, and it's almost entirely covered in non-descript ice -- what would be the value of having high-resolution imagery there?

> we have technology to identify a car license plate from space

We don't. State of the art imaging satellites are in ballpark of 20cm/px.

Here is what antarctica looks from a satellite: https://space-solutions.airbus.com/resources/satellite-image...

The high-res imagery on Google Earth mostly comes from aerial surveys, not satellite. If it's not economically worth flying a plane back and forth to survey -- and that's certainly true in Antarctica -- that's when you get the fuzzy civilian-grade satellite imagery or some cheap/public-domain out-of-date aerial photography.

I wonder if we just don't have many of these types of satellites in a polar orbit, since we don't have as big a need for that type of imagery for the poles?

Pretty sure the license plate/street view level data is from the cars that drive around with a lidar thing strapped to the top, not satellite data

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