Donut

<nobr>Donut</nobr>

Image Credit: Apollo 16 and Lunar Orbiter IV

Donut

Recently Danny Caes, the indefatigable explorer of ancient Apollo photos, reported that he had found two images of the concentric crater Crozier H. This LPOD shows the Apollo 16 view (in a sepia tone to indicate antiquity) and a Lunar Orbiter IV view from a previous LPOD. At the high sun of the Apollo view the concentric crater (upper left corner) looks like a big donut in a small saucer (or for American readers, a Cheerio in a spoon). The inner ring does not look like a crater rim as it would if it were a chance impact in a pre-existing crater. It is very rounded and doesnt look like any other type of lunar landform. Previously I have suggested that inner rings of concentric craters could be some type of volcanic feature, but that is total speculation based on a lack of real evidence of what the rings are. I am stumped what do you think