Mars 1M

Mars 1M was a series of two unmanned spacecraft which were used in the first Soviet missions to explore Mars. They were the earliest missions of the Mars program. The Western media dubbed the spacecraft "Marsnik", a portmanteau of Mars and Sputnik.

Mars 1M No.1, known in the west as Marsnik 1, Mars 1960A and Korabl 4, was destroyed in a launch failure on October 10, 1960. In 1962, NASA Administrator James E. Webb informed the United States Congress that NASA believed the mission was an attempt at a Mars flyby probe. Some Soviet scientists involved with the program at that time claim no knowledge of this mission, stating that only the second launch was an intended Mars mission. However, V. G. Perminov, the leading designer of planetary spacecraft at the Lavochkin design bureau, states that this mission was indeed intended for Mars and was identical to the later mission.

Mars 1M No.2, known in the west as Marsnik 2, Korabl 5 and Mars 1960B, was launched on October 14, 1960.

Both Mars 1M spacecraft were launched by Molniya rockets. The unproven third stage malfunctioned on both flights as cavitation in the fuel lines prevented the engines from developing adequate thrust, and, as a result, neither spacecraft achieved its initial geocentric parking orbit. Mars 1M No.2 reached an altitude of 120 km before reentry.

Soviet premier Nikita Khrushchev had planned to bring models of the Mars probes for showcasing at his visit to the UN that month, but as both launches failed, they remained packed.

The objectives of the mission were to investigate interplanetary space between Earth and Mars, to study Mars and return surface images from a flyby trajectory, and to study the effects of extended spaceflight on onboard instruments and provide radio communications from long distances.

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