[db48x]

No, that’s not it. I believe that these are not true images. They are instead effectively graphs of the time of flight of the radar signals. The vertical axis is flipped, putting Earth (or rather the radio telescope) “above” the image and the bearing of the radar signal along the x axis. The shading happens because some fraction of the radar signal refracts instead of reflecting. You can think of this as reflecting off of the interior of the asteroid rather than the surface, or as reflecting off of internal features such as density or composition changes.

Our eyes interpret it as a top–down view, or as a face–on view with lighting from one side, but it’s really more like a slice through the middle. Or rather, like a bunch of slices through the middle all stacked on top of each other, since the beam probably isn’t all _that_ narrow after traveling for a few million miles.

I wish I could find the paper though; press releases so often don’t bother linking to them. Maybe it hasn’t even been published yet? The observations were just 19 days ago.