Sputnik 1

"Sputnik" redirects here. For other uses, see Sputnik (disambiguation).

Sputnik 1
Replica of Sputnik 1 in the Museum of Space and Missile Technology (Saint Petersburg)
NamesСпутник 1
Object PS (Prosteishiy Sputnik)
Простейший Спутник-1
Elementary Satellite-1
Mission typeTechnology demonstration
OperatorOKB-1
Harvard designation1957 Alpha 2[1]
COSPAR ID1957-001B Edit this at Wikidata
SATCAT no.2[2] (The launch rocket has SATCAT no.1)
Mission duration22 days (achieved)
Orbits completed1,440[3]
Spacecraft properties
SpacecraftSputnik-1
ManufacturerOKB-1
Ministry of Radiotechnical Industry
Launch mass83.6 kg (184 lb)
Dimensions58 cm (23 in) diameter
Power1 watt
Start of mission
Launch date4 October 1957; 67 years ago (4 October 1957), 19:28:34 UTC
RocketSputnik 8K71PS[4]
Launch siteBaikonur Cosmodrome Site 1/5[4]
ContractorOKB-1
End of mission
DisposalAtmospheric entry
Last contact26 October 1957
Decay date4 January 1958[4]
Orbital parameters
Reference systemGeocentric orbit[5]
RegimeLow Earth orbit
Semi-major axis6,955.2 km
Eccentricity0.05201
Perigee altitude215 km (134 mi)
Apogee altitude939 km (583 mi)
Inclination65.10°
Period96.20 minutes
Instruments
Radio transmitter
20.005 and 40.002 MHz

Sputnik 1 (/ˈspʌtnɪk, ˈspʊtnɪk/, Russian: Спутник-1, Satellite 1), sometimes referred to as simply Sputnik, was the first artificial Earth satellite. It was launched into an elliptical low Earth orbit by the Soviet Union on 4 October 1957 as part of the Soviet space program. It sent a radio signal back to Earth for three weeks before its three silver-zinc batteries became depleted. Aerodynamic drag caused it to fall back into the atmosphere on 4 January 1958.

It was a polished metal sphere 58 cm (23 in) in diameter with four external radio antennas to broadcast radio pulses. Its radio signal was easily detectable by amateur radio operators,[6] and the 65° orbital inclination made its flight path cover virtually the entire inhabited Earth.

The satellite's success was unanticipated by the United States. This precipitated the American Sputnik crisis and triggered the Space Race, part of the Cold War. The launch was the beginning of a new era of political, military, technological, and scientific developments.[7] The word sputnik is Russian for satellite when interpreted in an astronomical context;[8] its other meanings are spouse or traveling companion.[9][10]

Tracking and studying Sputnik 1 from Earth provided scientists with valuable information. The density of the upper atmosphere could be deduced from its drag on the orbit, and the propagation of its radio signals gave data about the ionosphere.

Sputnik 1 was launched during the International Geophysical Year from Site No.1/5, at the 5th Tyuratam range, in Kazakh SSR (now known as the Baikonur Cosmodrome). The satellite traveled at a peak speed of about 8 km/s (18,000 mph), taking 96.20 minutes to complete each orbit. It transmitted on 20.005 and 40.002 MHz,[11] which were monitored by radio operators throughout the world. The signals continued for 22 days until the transmitter batteries depleted on 26 October 1957. On 4 January 1958, after three months in orbit, Sputnik 1 burned up while reentering Earth's atmosphere, having completed 1,440 orbits of the Earth,[3] and travelling a distance of approximately 70,000,000 km (43,000,000 mi).[12]

  1. ^ "Sputnik 1 (PS-1 #1)". Gunter's Space Page. 11 December 2017. Retrieved 16 May 2021.
  2. ^ "SL-1 R/B". n2yo.com.
  3. ^ a b Cite error: The named reference rswSM was invoked but never defined (see the help page).
  4. ^ a b c "Sputnik 1". Encyclopedia Astronautica. Archived from the original on 27 December 2016. Retrieved 8 January 2017.
  5. ^ Cite error: The named reference nssdc.orbit was invoked but never defined (see the help page).
  6. ^ Ralph H. Didlake, KK5PM; Oleg P. Odinets, RA3DNC (22 September 2008). "Sputnik and Amateur Radio". American Radio Relay League. Archived from the original on 11 October 2007. Retrieved 26 March 2008.{{cite web}}: CS1 maint: numeric names: authors list (link)
  7. ^ McDougall, Walter A. (Winter 2010). "Shooting The Moon". American Heritage. 59 (4). ISSN 0002-8738. Retrieved 3 January 2019.
  8. ^ "Display: Sputnik-1 1957-001B". NASA. 27 April 2021. Retrieved 16 May 2021. Public Domain This article incorporates text from this source, which is in the public domain.
  9. ^ "Sputnik 1, Earth's First Artificial Satellite in Photos". SPACE.com. 4 October 2020.
  10. ^ "APOD: October 3, 1998 – Sputnik: Traveling Companion". apod.nasa.gov. Public Domain This article incorporates text from this source, which is in the public domain.
  11. ^ Jorden, William J. (5 October 1957). "Soviet Fires Earth Satellite Into Space". The New York Times. Retrieved 28 December 2015.
  12. ^ "Sputnik-1 1957-001B". NASA. 27 April 2021. Retrieved 16 May 2021. Public Domain This article incorporates text from this source, which is in the public domain.