2. Pulsar Plus
The beat of Pulsar CP1133, as recorded from Earth, fed back through an alien rhythm box and accompanied by a Morse code message (ad astra per aspera, “to the stars through difficulty”) included on the Voyager Record. The aliens have folded in the skipping sound of a human heartbeat along with a composition specially made for Voyager that translates Kepler’s Harmonia Mundi — the music of the spheres — into a collection of pitches corresponding to the orbits of the six planets known during Kepler’s day. The sequence ends with Voyager’s audio readout of an electroencephalogram that tracks the thoughts of Voyager team member Ann Druyan as she ruminates on significant moments in human history as well as her then (1977) blooming romance with Carl Sagan.