Zond 2
The Soviets launched Zond 2 to Mars on November 30, 1964, but lost contact with the spacecraft in May of 1965.
Zond 2 carried a descent craft, a magnetometer probe, television photographic equipment, a spectroreflectometer, radiation sensors, a spectrograph to study ozone absorption bands, and a micrometeoroid instrument.
One of Zond 2's two solar panels failed during the mission and communications with the spacecraft were lost in early May, 1965. The spacecraft flew by Mars on August 6, 1965 at a distance of about 900 miles.
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