In 1963 Korolev's OKB proposed development of a massive nuclear-powered geosynchronous satellite, which would be launched by the N1 superbooster. The spacecraft, 25 m long, would have the form of a long cone followed by cylindrical sections. The cone would be the nuclear reactor; the conical section contained the communications equipment, on-board control systems, and cylindrical heat radiators for the reactor.

The orientation system would point the satellite to within 0.5 to 1 degrees accuracy. Three such satellites would provide global coverage. Average operating life was expected to be two to three years. In support of this project research was undertaken on a fast-neutron reactor with beryllium reflectors and a niobium case. Coolant cycle would use liquid lithium Li - Li-7. Thermal output of the reactor would be 6,000 kW and net average electrical output 600 kW. The reactor core had a diameter of 0.75 m, a length of 1.1 m, and a mass of 1,000 kg. The draft project of 1963 foresaw completion of system design in 1965 and flights from 1967. Although work continued throughout the 1960's on development of the reactor, the communications satellite itself was not approved.

Length: 25.00 m (82.00 ft). Maximum Diameter: 4.00 m (13.10 ft). Span: 5.00 m (16.40 ft). Mass: 16,000 kg (35,000 lb). Electrical System: Nuclear reactor. Electric System: 600.00 average kW. Associated Launch Vehicle: N1.

• Semenov, Yu. P., S P Korolev Space Corporation Energia, RKK Energia, 1994. ISBN: 1896522815. Dual English/Russian language picture book of the history of the Energia Corporation. Many unique photos and drawings of Korolev's rockets and spacecraft. Republished by Apogee books in 2000. More at amazon.com...

• Vetrov, G S, S. P. Korolev i evo delo, Nauka, Moscow, 1998. ISBN: 5020036846. The collected papers of Soviet Chief Designer Korolev. A tremendous source of new information and insight on the Soviet space program. Russian language. More at amazon.com...