PIONEER IV INSTRUMENT PACKAGE
This is the back-up Pioneer IV instrument package. The conical antenna, lifted here to show the instruments, is made of fiberglass and sprayed with gold. The alternating black and gold stripes help maintain a proper internal temperature by controlling the amount of heat absorbed from sunlight.
On the top of the instrument package are two Geiger-Mueller tubes that measured radiation. One is shielded so that only high-energy particles can register. Beneath the tubes is supporting circuitry, a radio transmitter enclosed in a central band of batteries, and, lastly, the lens of a photoelectric scanning device. This lens was designed to trigger a signal to Earth when it "saw" the far side of the Moon.
This compact design weighed 6.26 kilograms (13.8 pounds).

JUNO II
The Juno II 4-stage launch vehicle included a liquid-propellant Jupiter missile plus 3 stages of solid- propellant rockets in groups of 11, three and one, respectively. The upper three stages were spun during launch to provide stabilization.The Juno II was the launch vehicle for Pioneer IV. The Able-Baker Primate Capsules were carried in a Jupiter missile nose cone.
Height: 23.4 meters (76.7 feet)
Lift-off weight: 55,000 kilograms (121,000 pounds)
Thrust: First stage 68,000 kilograms (150,000 pounds)
Second stage 9000 kilograms (19,800 pounds)
Third stage 2500 kilograms (5400 pounds)
Fourth stage 836 kilograms (1800 pounds)

Able-Baker Primate Experiments