In honor of the 78th birthday of electronic music pioneer Robert Moog, tomorrow’s doodle on the Google homepage will feature a fully functioning recreation of his legendary Moog synthesizers.  The doodle is equipped with working knobs for mixer, oscillators, filter, and envelope that spell out “Google”, and it has a mod wheel that you can control with your keyboard’s arrow keys. Much like the Les Paul Google Doodle that featured a playable guitar, the Moog doodle page will feature an image of a tape recorder that allows you to record up to four tracks and share your creations through Google+. The doodle is already live on the Japanese and Australian website, but it will land in the United States elsewhere tomorrow for Moog’s May 23 birthday.