• Post category:Space Probes
  • Reading time:5 mins read


Sputnik rocket performed the world’s first satellite launch, placing the satellite “Sputnik 1” into a low earth orbit, on the 4th of October, 1957. The rocket was designed by the legendary Soviet Rocket engineer and spacecraft designer — Sergie Korolev. The rocket was a modified form of R-7 Semyorka — the world’s first intercontinental ballistic missile developed by Soviets during the Cold war.

Many of us know that Sputnik 1 was the first satellite to space. Another lesser-known fact is the race for the second satellite in space. Together with the Jet Propulsion Laboratory (JPL), the Army Ballistic Missile Agency (USA) built Explorer 1 and launched it on 31 January 1958. Before work was completed the Soviet Union launched a second satellite, Sputnik 2 along with a living animal, a Soviet Space dog named Laika, on 3 November 1957.

Technical Details

Two versions of the Sputnik were built—

  • Sputnik-PS (8K71PS) launched Sputnik 1 and Sputnik 2 satellites.
  • Sputnik (8A91) launched Sputnik 3 on 15 May 1958 after having failed to launch a satellite in April 1958.

The Sputnik rocket has a unique configuration where four break-away liquid-fueled engines surround a central core. The core acts as a “second stage” in effect after the other four engines are jettisoned.

Sputnik 8K71PS Rocket
Sputnik 8K71PS.
Photo credits: GW_Simulations


No. boosters: 4
Engines: 1 RD-107
Thrust: 970 kN
Specific impulse: 306 s
Burn time: 120 s
Propellant: LOX/Kerosene

Core stage

Engines 1 RD-108
Thrust 912 kN
Specific impulse 308 s
Burn time 330 s
Propellant LOX/Kerosene

Sputnik Satellite

Sputnik 1 weighed 83 kilograms and was 58 centimeters wide. This measure refers to the satellite’s body; Sputnik 1 also featured two double-barreled antennas, the larger of which was 3.9 meters, long. Sputnik 1 was powered by three silver-zinc batteries, which were designed to operate for two weeks. The batteries exceeded expectations, as the satellite continued sending out its radio signal for 22 days.

The spacecraft continued lapping Earth in silence for a few more months, its orbit decaying and sending the craft steadily closer to the planet. The satellite finally burned up in the atmosphere on Jan. 4, 1958.

Though Sputnik 1 was small, it was quite reflective and therefore visible from Earth through a pair of binoculars (and perhaps even with the naked eye, if you had good vision and knew exactly where to look). Many people reported seeing the satellite overhead in late 1957, but experts think most of these sightings actually involved the R-7. The rocket’s 26 m long core stage also reached orbit, and it was covered with reflective panels to make tracking it easier.

An engineer inspecting Sputnik 1
An engineer inspecting Sputnik 1
Credits: soloesciencia.com

Good to know

The word “sputnik” is Russian for satellite when interpreted in an astronomical context and its other meanings are spouse or traveling companion.

30k USSR stamp depicting Sputnik 1 orbiting the Earth, the Earth orbiting the Sun and the Sun orbiting the centre of the Milky Way galaxy
30k USSR stamp depicting Sputnik 1 orbiting the Earth, the Earth orbiting the Sun, and the Sun orbiting the center of the Milky Way galaxy

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