In early 1966, the Soviets hastily put together an interim lunar orbiter program, the Ye-6S, partly to upstage the American Lunar Orbiter project, and partly to commemorate the 23rd Congress of the Communist Party held in March 1966.

Engineers quickly designed a set of two rudimentary probes using the old Ye-6 (lander) buses for these missions. The first of these was prepared in less than a month but failed to leave Earth orbit.

During Earth orbit operations, the Blok L upper stage lost roll control and failed to fire to send the probe towards the Moon. The official Soviet media named the stranded satellite Kosmos 111 which reentered two days after launch.


Siddiqi, Asif A. Beyond Earth: A Chronicle of Deep Space Exploration, 1958-2016. NASA History Program Office, 2018.

Related News