 Pioneer P-30 was almost identical to the earlier Pioneer P-3 satellite which failed, a 1-meter diameter sphere with a propulsion system mounted on the bottom giving a total length of .The mass of the structure and aluminum alloy shell was about and the propulsion units roughly .Four solar panels, each and containing 2200 solar cells in 22 100-cell nodules, extended from the sides of the spherical shell in a "paddle-wheel" configuration with a total span of about .