Mariner 3,4

Part of the Mariner program

Mariner 4 provided the first up close pictures of Mars. After a 228 day cruise, Mariner 4 passed Mars at a distance of 9,846 kilometers on July 14, 1965. During its encounter, the spacecraft took 22 television pictures that covered about 1 percent of the Martian surface. The images revealed a vast, barren wasteland of craters strewn about a rust-colored carpet of sand. Once past Mars, Mariner 4 orbited the Sun prior to returning to the vicinity of Earth again in 1967. Engineers then decided to use the aging craft for a series of operational and telemetry tests to improve their knowledge of the technologies that would be needed for future interplanetary spacecraft. All operations ceased on December 20, 1967. A sister ship, Mariner 3, was launched three weeks earlier than Mariner 4, but was lost when the launch vehicle's nose fairing failed to jettison.

Spacecraft
3-axis stabilized using cold gas thrusters. Four deployed solar panels were kept oriented toward the Sun. S-Band communications using LGA or HGA.

Payload
Magnetometer, charged particle sensors, cosmic-ray telescope, television camera. Tape recorder stored 21 pictures.

Country of Origin	United States
Customer/User	NASA
Manufacturer(s)	JPL
Orbit	Solar orbit - 8 month direct trajectory
Related Sites	JPL Mariner 4 Summary

Launch Facts

Name	Int'l Desig.	Date	Site	Vehicle	Orbit	Mass(kg)
Notes
Mariner 3	1964-073A	11/5/64	ESMC	Atlas Agena D	Solar	260
Mars probe; launch fairing failure prevented Mars flyby
Mariner 4	1964-077A	11/28/64	ESMC	Atlas Agena D	Solar	260
Mars probe