This comment below this answer to How was it possible for the Apollo 11 to film and take pictures with such radiation? links to the svengrahn.pp.se post Luna 3 - the first view of the moon's far side.
It shows the annotated image below of Luna-3. The image is a partial cut-away view, the lower half shows the external area and the upper half shows some of the internal components I believe.
Near the "bottom" of the spacecraft (the end with the Pivoting antennas and Lunar sensors) there is something labeled "Cover of illuminator".
Question: What did Luna 3's illuminator illuminate and why did it need a cover?
One of the origins of Luna-3 was the work by Boris Raushenbakh on attitude control started in 1955 in the NII-1 rocket research institute of the Ministry of Aviation. This work was co-ordinated with Korolev's design bureau and had as its goal stabilised photo-reconnaissance satellites. Raushenbakh's group was contracted by the lunar project section Korolev's design bureau OKB-1 to design the attitude control for the E-2 variant of lunar exploration craft intended to image the Moon's hidden side. The manager of the lunar probe project at OKB-1 was Gleb Maksimov. An excellent account of these early Soviet lunar missions can be found in (4) and (14). A cutaway sketch of the space probe with a Soviet-era translation of Russian captions added is shown below.
4Asif A. Siddiqi, "First to the Moon", Journal of the British Interplanetary Society, Vol.51, pp.231-238, 1998.
14Timothy Varfolomeyev, Journal of the British Interplanetary Society, Vol.52, pp.157-160, 1999.
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