[Animats]

Synthetic Aperture Radar. What you're really seeing here is what happens when you try to put together a 3D image from an angled line scan from a moving scanner. There isn't enough information to do this perfectly, so you get artifacts on tall objects. You can see somewhat similar artifacts in Google Earth when looking down on tall objects for which they don't have full elevation data, like trees.

What's impressive is that they're getting 50cm resolution from orbit. Doing this from aircraft is nothing new; that's been going on for decades. But 50cm from a satellite? That's an achievement.

[derstander]

In some sense achieving high resolution imagery from orbit is simpler in that SAR requires motion compensation on the order of a wavelength. Planes are subject to all sorts of motion like turbulence whereas a satellite’s motion is often far more predictable. Closing the link budget can certainly be more challenging given longer ranges and size, weight, power, and cooling constraints for satellites though.

[andi999]

I read it is 50cm because it is the legal (not technical) limit.

[nick_kline]

Reading that long article where the writer didn't have awareness that they should define that term reminds me of reading in grad school. Please define the main term in your articles, people! Geeze.