Vesta's south pole

[mmcirvin]

Dawn finally gets what appear to be recognizable pictures of Vesta's enormous south polar basin and central peak, here and here. If it's an impact crater, it's really eroded-looking, without a sharp ridge; against Vesta's spheroidal surface it looks more like a flat area with a bump in the middle. But there are lots of strange grooves running across it, reminiscent of the ones on Phobos and some other objects.

Comments

[skapusniak.livejournal.com]

My planetary photo interpretation skills clearly suck, everything looks convex rather than concave to me on these :(

Which way is South on these again?

[pauldrye.livejournal.com]

Turn the picture sideways, or even upside down. It changes the apparent light angle so that concave looks properly convex to your brain.

[mmcirvin.livejournal.com]

In the second picture, South is pointing almost straight out of the picture plane. The peak is near the center at 7 o'clock from the exact center. In the first picture, the angle is different and it's nearer the bottom.

The huge crater (if it is an impact crater, which it may or may not be) isn't actually very concave, because it covers almost a whole hemisphere of a convex object. It's more like a flattening of the southern hemisphere with a big bump in the middle. But considered relative to a symmetrical ellipsoid, it's a basin.