Luna 1

Luna 1, also known as Mechta, E-1 No.4 and First Lunar Rover, was the first spacecraft to reach the vicinity of Earth's Moon, the first spacecraft to leave Earth's orbit, and the first to be placed in heliocentric orbit. Luna 1 was launched as part of the Soviet Luna programme in 1959. Initially intended as a Moon impactor, a malfunction in the ground-based control system caused an error in the upper stage rocket's burn time, and the spacecraft missed the Moon by 5,900 km (more than three times the Moon's radius). Nevertheless, Luna 1 became the first human-made object to reach heliocentric orbit and was dubbed "Artificial Planet 1" and renamed Mechta (Dream). Luna 1 was also referred to as the "First Cosmic Ship", in reference to its achievement of Earth escape velocity.

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