Jean Luc Picard impersonating Korgano.
Korgano was a character in ancient D'Arsay mythology. He was the nemesis of Masaka, the one who controlled her and made her vanish from the sky. D'Arsay was represented by the D'Arsay archive, which was intercepted by the Enterprise-D in 2370. Enterprise-D Captain Jean-Luc Picard felt that Korgano was the moon and Masaka was the sun. Picard assumed the identity of Korgano when he attempted to convince the archive to release his ship. (TNG: "Masks")