Mariner 3 Launches Toward Mars but Loses Power After Its Shroud Fails

A Planned Flyby of Mars

Mariner 3 was one of two identical spacecraft built by the Jet Propulsion Laboratory for the 1964 Mars launch opportunity. The Mariner program had already sent Mariner 2 past Venus in December 1962. The new craft carried a television camera and several instruments for measuring magnetic fields, charged particles and cosmic dust, and it was meant to fly past Mars in the summer of 1965. Windows for launching to Mars open only about once every twenty-six months, when Earth and Mars are suitably placed, so a failure in November meant waiting until the next opportunity.

The Launch

Mariner 3 lifted off from Cape Kennedy in Florida on November 5, 1964, on an Atlas-Agena D rocket. The first stages worked as planned, and the spacecraft reached the trajectory intended to take it to Mars. The problem came with the payload shroud, the fairing that covers the spacecraft during the climb through the atmosphere. The shroud was supposed to split and fall away, and the data returned to the ground showed that it had not separated properly.

What Went Wrong

With the shroud still attached, the spacecraft's solar panels could not unfold in the normal way, and the craft had to rely on its batteries. Mariner 3 was therefore unable to recharge, and its power ran down within hours of launch. Engineers at NASA and JPL later concluded that the shroud had been the cause, and that part of its structure had probably collapsed or interfered with the spacecraft. No further useful data came back. Mariner 3 went into orbit around the Sun, where it is still reported to remain.

Mariner 4 Follows

The second spacecraft, Mariner 4, was already being prepared at the Cape. Engineers changed the design of the shroud, and Mariner 4 was launched on November 28, 1964, within the same launch period. Its solar panels opened correctly. On July 14 and 15, 1965, it flew past Mars at a distance of roughly 9,800 kilometers and sent back 21 pictures, along with measurements suggesting a thin atmosphere. The loss of Mariner 3 is recorded by NASA as a launch failure rather than a failure of the spacecraft's own instruments.

The Mariner Series

Mariner was a series of ten spacecraft launched between 1962 and 1973 to study Venus, Mars and Mercury. Mariner 2 passed Venus in December 1962. Mariner 4 reached Mars in 1965, and Mariner 5 flew past Venus in 1967. Mariner 6 and 7 flew past Mars in 1969, Mariner 9 became the first spacecraft to orbit another planet when it reached Mars in November 1971, and Mariner 10 visited Venus and Mercury in 1973 and 1974. Mariner 3 and Mariner 4 each weighed about 260 kilograms and used four solar panels to power their systems.