Question: On what planet was a large rectangular outcrop that is composed mainly of sandstone first observed by an English astronomer born 1618?
Sentence (from "Horrocks Block"): Horrocks Block ( ) is a large rectangular outcrop that is composed mainly of sandstone, lying on the north side of Venus Glacier, 2 nmi southwest of the Keystone Cliffs, on the east side of Alexander Island, Antarctica.
Relevant evidence: Yes