This astrobleme looks like a nipple.
Here's a word of the day that can easily be morphed into astroacne. Hey, I think I just coined that....anyways... Your word of the day is astrobleme. Use astrobleme in a sentence (?)
The local astrobleme is about the only interesting feature of that area. It's a favorite field trip site for school kids.
"Impact structure" is synonymous with the less commonly used term astrobleme meaning "star wound"---a term which, I might add , is devilishly difficult to include in everyday conversation, just as astroacne would be.
(I feel as if I have sailed far and wide on this one.)