Satellite construction project

The history of the Sputnik 1 project dates back to 27 May 1954, when Sergei Korolev addressed Dmitry Ustinov, then Minister of Defense Industries, proposing the development of an Earth-orbiting artificial satellite. Korolev also forwarded Ustinov a report by Mikhail Tikhonravov with an overview of similar projects abroad.^[5] Tikhonravov emphasized that an artificial satellite is an inevitable stage in the development of rocket equipment, after which interplanetary communication would become possible.^[6] On 29 July 1955 the U.S. President Dwight Eisenhower announced, through his press secretary, that the United States would launch an artificial satellite during the International Geophysical Year (IGY).^[7] A week later, on 8 August the Presidium of the Central Committee of the CPSU approved the idea of creating an artificial satellite.^[8] On 30 August Vasily Ryabikov – the head of the State Commission on R-7 rocket test launches – held a meeting where Korolev presented calculation data for a spaceflight trajectory to the Moon. They decided to develop a three-stage version of the R-7 rocket for satellite launches.^[9]

On 30 January 1956 the Council of Ministers of the USSR approved practical work on an artificial Earth-orbiting satellite. This satellite, named "Object D", was planned to be completed in 1957-58; it would have a mass of 1,000 to 1,400 kg (2,200 to 3,090 lb) and would carry 200 to 300 kg (440 to 660 lb) of scientific instruments.^[10] The first test launch of "Object D" was scheduled for 1957.^[6] According to that decision, work on the satellite was to be divided between institutions as follows:^[11]

• USSR Academy of Sciences was responsible for the general scientific leadership and research instruments supply
• Ministry of Defense Industry and its main executor OKB-1 were assigned the task of creating the satellite as a special carrier for scientific research instruments
• Ministry of Radiotechnical Industry would develop the control system, radio/technical instruments and the telemetry system
• Ministry of Ship Building Industry would develop gyroscope devices
• Ministry of Machine Building would develop ground launching, refueling and transportation means
• Ministry of Defense was responsible for conducting launches

By July 1956 the draft was completed and the scientific tasks to be carried out by a satellite were defined. It included measuring the density of the atmosphere, its ion composition, corpuscular solar radiation, magnetic fields, cosmic rays, etc. Data, valuable in creating future satellites, were also to be collected. A ground observational complex was to be developed, that would collect information transmitted by the satellite, observe the satellite's orbit, and transmit commands to the satellite. Such a complex should include up to 15 measurement stations. Due to the limited time frame, they should have means designed for rocket R-7 observations. Observations were planned for only 7 to 10 days and orbit calculations were expected to be not quite accurate.^[12]

Unfortunately, the complexity of the ambitious design and problems in following exact specifications meant that some parts of 'Object D', when delivered for assembly, simply did not fit with the others, causing costly delays. By the end of 1956 it became clear that plans for 'Object D' were not to be fulfilled in time due to difficulties creating scientific instruments and the low specific impulse produced by the completed R-7 engines (304 sec instead of the planned 309 to 310 sec). Consequently the government re-scheduled the launch for April 1958.^[6] Object D would later fly as Sputnik 3.

Fearing the U.S. would launch a satellite before the USSR, OKB-1 suggested the creation and launch of a satellite in April-May 1957, before the IGY began in July 1957. The new satellite would be simple, light (100 kg or 220 lb), and easy to construct, forgoing the complex, heavy scientific equipment in favour of a simple radio transmitter. On 15 February 1957 the Council of Ministers of the USSR approved this, providing for launching the simplest version satellite, designated 'Object PS'.^[13] This version also facilitated the satellite to be visually tracked by Earth-based observers while in orbit, and transmit tracking signals to ground-based receiving stations.^[13] Launch of two satellites PS-1 and PS-2 with two R-7 rockets (8K71) was allowed, but only after one or two successful R-7 test launches.