[crater] The interior of this crater has a relatively dark-hued floor, a feature it has in common with other craters to the west and northwest that form part of the Mare Australe. The floor is level and mostly featureless, except for some deposits in the northwest corner. The rim is more heavily worn in the northwest corner than elsewhere, ...
Found on
http://en.wikipedia.org/wiki/Cassegrain_(crater)
Reflecting scheme in antennas and telescopes having a primary and a secondary reflecting surface to 'fold' the EMF back to a focus near the primary reflector.
Found on
http://www.encyclo.co.uk/visitor-contributions.php
No exact match found.
