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Traditional Micro-satellites list  1957-1969

Sputnik-I (PS1).

The first (micro)satellite, Sputnik meaning "companion" or "fellow traveller", was launched from the NIIP-5 test range in Kazakhstan (Kazakh SSR) on Friday 10:28:04pm Moscow time October 4th 1957, on a 260 tonnes SS-6 (aka 8K71PS) booster (ser.no. M1-1PS), into a 65.1 degree inclination 215 x 939km orbit from Yuratum (Baikonur). It is reported that it entered an orbit lower than intended due to a failure in the launch vehicle which cut short the core stage firing time by 1s. Pictures [ 1 (103k), 2(172k) ] show it was spherically shaped sphere with 0.58m diameter, and weighed 83.6kg. The polished aluminium sphere was hermetically sealed with nitrogen to provide thermal control by convection, and contained a 20.005 and 40.002MHz beacon. Two pairs of flexible whip antennas measuring 2.4 and 2.9m each, were folded inside the nose cone of the rocket and automatically deployed once in orbit. The satellite's main purpose was to provide data about the Earth's gravity field by observing the satellite in orbit, as a contribution to the International Geophysical Year. The signals emitted were used in the characterisation of the ionosphere. The satellite transmitted telegraphic impulses of 300ms duration [recording (WAV, 111k), observer report]. The frequency and delay between pulses were modulated in order to relay information of nitrogen pressure and temperature. The satellite employed chemical batteries. The radio transmitter failed after three weeks, and Sputnik-I decayed January 4^th 1958. On the 40^th anniversary, a Sputnik replica was launched.

References
[1] Sputnik 1957 - Memories of an old-timer, Ernst Stuhlinger, JBIS VOL 52 No 7/8, Jul/Aug99

Explorer-I.

The United States answer to Sputnik-I (and the much larger Sputnik-II), launched (picture) on January 31st 1958 on a Jupiter C (JUNO) launcher. It was cylindrical in shape (picture) also containing the upper stage,  measuring 2.03m long and 150mm diameter, and weighed 13.6kg. It was launched into a 356 x 2548km 33.24 degree inclination orbit, and continued operating until 23 May 1958 using 108MHz communication links [recording (WAV, 108k), observer report]. It completed 58,000 orbits and decayed Mar 31 1970. It measured the thermal and radiation environment of space, and micrometeorites, and was to later turn out to be the first confirmation of the existence of the van Allen radiation belts. Explorer 1 was the first in an extensive series of scientific satellites to study the environment of space. The low power downlink delivered 10 to 20mW whilst the higher power downlink delivered 60mW. Each transmitted continuously 8 channels of information. Four stiff wire antennas were carried weighted at the end, allowing them to deploy when the spacecraft was spun up. The spacecraft contained 12 micrometeorite erosion gauges, external temperature gauges, an ultrasonic microphone for micrometeorite detection, and a cosmic ray detection experiment.
Explorer 1 was designed to spin about its long axis, but it soon was in a flat spin, tumbling end over end, and it was concluded that the turnstile antennas were acting as mechanical energy transducers, absorbing spin energy from the minor axis, and converting it to the major axis. A model of explorer can be seen in the Air and Space Museum in Washington D.C., USA. More...
[Explorer-1 at JPL]

 

Explorer-2.

Launch failure on the 5th March 1958

Vanguard-1.

Launched on the 17th March 1958, the 160mm diameter satellite carried miniature radio transmitters, a solar radiation sensor and many other instruments. Glass windows allowed solar cells to be carried to re-charge the batteries. The satellite operated for 7 years, but will be the oldest satellite in orbit for many centuries before it finally decays. More...
[Vanguard page in Sweden]

Explorer-3.

Launched on a Jupiter C launcher on the 26th March 1958, it was similar to Explorer 1. It stopped transmitting data on the 16th March, and re-entered on the 28th June 1958.

 

Explorer-4.

A 17kg version of the Explorer series, launched on a Jupiter C launcher on the 26th July 1958, it measured radiation from project Argos. It stopped transmitting data on the 23rd October, as it re-entered.

 

Explorer-5.

Jupiter C Launch failure from Cape Canaveral on the 24th August 1958 as the upper stage fired in the wrong direction. A 17kg spacecraft intended to measure radiation.

 

SCORE.

The U.S. Army's SCORE, Signal Communication by Orbiting Relay, was launched on the 31st December 1958 on an Atlas B launcher from Cape Canaveral into an elliptical orbit. This spacecraft carried messages on a tape recorder which was used at one point to carry a Christmas greeting from President Eisenhower. The satellite weighed 69.9kg, operated for two weeks, and re-entered on the 21st January 1959.
References
[1] The Talking Satellite: A reminiscence of project score, Deane Davis, , JBIS VOL 52 No 7/8, Jul/Aug99

 

Vanguard-2.

Launched on the 17th February 1959 on SLV-4 from the Eastern test range into a 557x3319km orbit with 32.9 degree inclination. The spacecraft employed the same 510mm diameter Magnesium Alloy spherical shell as used for Vanguard-1. It carried a redundant set of transmitters, and primary mercury batteries. A single photocell was carried behind a telescope such that the satellite spin would scan the Earth and return meteorological style imagery. Unfortunately the third stage is believed to have bumped into the satellite shortly after deployment, causing a random tumble. Despite this, the spacecraft operated for 26 days, and returned valuable statistics about the Earth illumination as seen from space. The satellite was developed by an NRL team, but their first launch under NASA management.

Vanguard-SLV-5, 1959

The launch of SLV-5 carrying Vanguard-3a and 3b failed on the 13th April 1959, leaving the vanguard 3a and 3b designation for later successful mission (A common practice at that time). The two spacecraft were connected by a 64mm and 445mm long tube to be separated once in orbit. Vanguard 3a was spherical in shape measuring 330mm diameter and weighed 10.6kg. It carried a precision magnetometer in a fibreglass and phenolic resin sphere. Vanguard-3b was a passive plastic laminate and aluminium balloon to inflate to 0.76m in diameter, to be tracked photographically to measure the Earth's atmospheric density.

Vanguard-SLV6, 1959

The launch of the SLV6 on the 22nd June 1959 resulted in another failure. It carried a standard Vanguard satellite weighing 10.8kg. It was to measure the Earth's radiation budget in a 48 degree inclined orbit..

Explorer-S1.

Juno launch failure from Cape Canaveral on the 16th July 1959. The 42 kg spacecraft was destroyed.

Explorer-6.

Launched on a Thor Able from Cape Canaveral on the 7th August 1959 into a 47 degree inclined orbit. The 64.5 kg spacecraft carried 4 paddlewheel 0.5m^2 solar panels and measured 0.66m diameter, and a re-chargeable battery. The spacecraft was used for observing radio wave propagation in the ionosphere, and mapped the Earth magnetic field and cloud cover using transmitted data from a camera. The satellite was active until the 6th October 1959, and decayed in July 1961.

Vanguard-3.

Launched on a modified launch vehicle, the SLV-7, Vanguard-3 was placed in orbit on the the 18th September 1959. The satellite weighed 23.8kg and measured 508mm in diameter, although in orbit the X-248 third stage remained attached making the total mass 43kg. It carried a suite of instruments to monitor solar X-ray emissions and study the radiation and micrometeoroid environment. A proton magnetometer was also carried in a 660mm tall conical fibreglass housing, with the capability to measure in the kilohertz frequency range.

Explorer-7.

Launched on the 13th October 1959 from Cape Canaveral into a 557x1088km orbit inclined at 50 degrees. The 41kg  spacecraft returned magnetic field data and reported on solar flares until it ceased transmissions on the 24th July 1961.

Explorer-S46.

Juno-2 launch failure from Cape Canaveral on the 23rd March 1960. The 16 kg spacecraft was destroyed.

 

Echo-1

A NASA 75.9kg passive reflector satellite launched on the 12th August 1960 on a DELTA from the Eastern test range into a 1524x1684km orbit inclined at 47.2 degrees. It decayed on the 24th May 1968.

Explorer-8, 1960 Xi 1.

A 41kg satellite launched on the 3rd November 1960 on a Juno launcher into a 415 x 2267km orbit inclined at 49.9 degrees. Its structure was Aluminium, and like two truncated coned connected at the base, measuring 702mm in height and diameter. Explorer 8 carried instruments to aid study of radio wave propagation through the ionosphere. It measured electron density and distribution in both time and space. Other satellites in the series included Explorer 20, 22 and 27, Ariel 1, Allouette, ISIS X, FR-1, Esro 1, ISIS A, Esro 1B, ISIS B and Ariel 4. It confirmed the existence of a Helium layer in the ionosphere. It stopped transmitting on the 28th December 1960

OSCAR-1, a-Kappa 2.

The first radio amateur satellite launched piggyback on the 12th December 1961 2040UTC by the USAF from Vandenberg AFB on a Thor Agena B launcher with Discover 36 (a cover for the KH-3 CORONA spy satellite Mission 9029), into a 372x211km inclined at 81 degrees. OSCAR stands for Orbital Satellite Carrying Amateur Radio. The satellite was built in a garage workshop, box shaped with a single monopole antenna. It was battery powered and weighed 4.5kg and contained a 0.14W VHF 144.98MHz beacon transmitting Hi-Hi in Morse code [recording (WAV, 111k), observer report] and a battery. It transmitted until the 1st January, and completed 312 orbits before re-entering the atmosphere on the 31st January 1962.

Picture (right) courtesy of AMSAT

Ariel-1.

Ariel-1, the first British satellite was launched on the 26th April 1962 on a DELTA from Cape Canaveral into a 389x1214km orbit inclined at 54 degrees. The 60kg microsatellite was used to study ionospheric and X-ray data until November 1964. A picture (Science Museum, London, UK) shows the satellite was basically spherical measuring 30mm in height and 570mm in diameter, with four solar paddles and various booms.

 

Relay-1.

Launched on the 13th December 1962 on a Thor Delta launcher, the 78kg satellite was designed by RCA for NASA to test intercontinental microwave communications, and measure the radiation environment. It contained a 1.7233-1.727/4.165-4.175GHz transponder, offering 300 simplex voice channels between Europe and the U.S. A picture shows the spacecraft measured 760mm in diameter and 812mm height (including a 450mm diameter antenna). It employs a space structure with three co-axial rings, onto which the solar arrays are mounted. It stopped transmission on the 2nd February 1965. A model of the spacecraft can be examined at the NASA Goddard visitor centre. The spacecraft was launched into a 1317x7442km inclined at 47.5 degrees from the Eastern Test Range. Experiments were conducted until February 1965.

 

OSCAR-2, Chi 2.

Radio amateur satellite launched piggyback on a Thor-Agena B launcher with the USAF spy satellite KH-4 MURAL/CORONA Mission 9036 from Vandenberg AFB on the 2nd June 1962 0032UTC, into a 384x206, 73 degree inclined orbit. It was similar to OSCAR-1, but its keying rate at 144.99MHz was made to change with satellite temperature. It was battery powered and seized transmitting on the 20th June, and re-entered on the 21st June.
Picture (right) courtesy of AMSAT  

 

Telstar-1.

The first commercial spacecraft built by Bell Telephone Laboratories, and launched on the 10th July 1962 on a Thor Delta launcher from the Eastern Test Range into a 936x5653km orbit inclined at 44.8 degrees. A picture shows the satellite was spherical in shape, with 3600 solar cells. It carried an active broadband 6.39/4.17GHz transponder, offering 600 voice channels and one TV channel. Telemetry was PCM/FM/Am at 136MHz. The spacecraft weighed 77kg, and operated until the 21st February 1963.

 

SYNCOM-1.

The first communication satellite to be placed into Geostationary orbit. The Hughes experimental satellite for NASA was launched on the 14th February 1963 on a Thor Delta into a 34392x36,739km orbit inclined at 33.3 degrees. Radio contact was lost after it was placed in orbit. The satellite was cylindrical in shape measuring 710mm in diameter and 393mm in height. It weighed 39kg.

 

Telstar-2.

A communications spacecraft built by Bell Telephone Laboratories, and launched on the 7th May 1963 on a Delta launcher from the Eastern Test Range into a 966x10,808km orbit inclined at 42.7 degrees. The spacecraft weighed 79kg, and operated until the May 1965.

 

SYNCOM-2.

Communication satellite placed in Geostationary orbit of 35584x36693 inclined at 33.1 degrees. The satellite was launched on the 26th July 1963 on a Thor Delta, and a picture shows it was similar to Syncom-1. It was built by Hughes for NASA and placed over the Atlantic and began regular service on the 16th August. It demonstrated the feasibility of Geostationary satellite communications, and was the forerunner of the INTELSAT series of satellites.

Explorer-18.

Launched on the 23rd November 1963 from a DELTA into a 125,000x202,000km orbit, the Interplanetary Monitoring Platform were employed to measure the radiation environment during the 11 year solar cycle. The spacecraft weighed 62kg, and its power supply delivered 35W.

 

Relay-2.

Similar to Relay-1 was launched on the 21st January 1964 on a Thor Delta launcher for NASA into a 1,993x7,508km inclined at 46.6 degrees from the Eastern Test Range. The spacecraft was built by RCA. It offered experimental microwave communication between Japan and the U.S. It seized transmission on the 23rd May 1964

 

Ariel-2.

The 68kg Ariel-2 was launched from Wallops I on a Scout on the 27th March 1964 into a 285x1362km 52 degree inclined orbit. It failed in November 1964 and re-entered on the 18th December 1967.

 

SYNCOM-3.

A communications satellite placed in Geostationary orbit. The satellite was launched on the 19th August 1964 on a Thor Delta, and was similar to Syncom-1. It was placed over the Pacific and began service on the 23 September to provide coverage of the Tokyo Olympics, and to relay teletype messages to aircraft on the Honolulu to San Francisco route. It was handed over to the DOD on the 1st January 1965.

San Marco-1

San Marco-1, the first Italian microsatellite was launched on the 15th December 1964 on a Scout from Wallops, into a 194x697km orbit inclined at 38 degrees. The 24kg satellite measured atmospheric density until it re-entered on the 13th September 1965.

 

OSCAR-3, 1965-016F.

Radio amateur satellite launched piggyback with 7 further USAF satellites on a Thor Agena launcher from Vandenberg AFB on the 9th March 1965, into a 924x891km, 70.1 degree inclined orbit. It weighed 16.3kg, and carried a VHF 144/145MHz transponder with four monopole antennas.
Picture (right) courtesy of AMSAT  

 

EarlyBird (INTELSAT-I F1)

The first commercial communications satellite built by Hughes, and launched on the 6th April 1965 on a Thrust Augmented Delta launcher (TAD). The satellite was cylindrical in shape, measuring 710mm diameter and 584mm in height, weighed 38.6kg and delivered 40W of power. The satellite was operated by COMSAT in co-operation with the International Telecommunication Satellite Consortium (INTELSAT). It carried two transponders offering a total of 50Mhz bandwidth, enough for 480 analogue telephone channels. It was capable of television broadcast forwarding between Europe and the United States, on 6.301GHz/4.801GHz and 6.390GHz/4.161GHz.

EarlyBird was also the first satellite to be insured, albeit only for third party liability and pre-launch failures. Previously the insurance business had considered the space business too risky.
Picture (right) courtesy of Hughes.

 

Telstar-2.

Commercial spacecraft built by Bell Telephone Laboratories, and launched on the 7th May 1965 on a Thor Delta launcher. The satellite was spherical in shape 0.87m in diameter, and weighed 79.5kg, with 3600 solar cells. It carried an active broadband 6.39/4.17GHz transponder, offering 600 voice channels and one TV channel. Telemetry was PCM/FM/Am at 136MHz and 4.08GHz.

 

A-1 (Asterix).

The first French national launch on the Diamant launcher on the 26 November 1965 from Hammaguir in Algeria of the first French satellite A-1, into a 1768x528km, 34 degree orbit. The 41.7kg satellite transmitted for two days, with the main mission to test the diamant launcher.
Picture (right) courtesy of CNES

 

FR-1 1965-101A

FR-1, the first French satellite was launched into a 780km orbit on the 6th December 1965 on a Scout launcher from Vandenberg AFB. The satellite was used to study the ionosphere.
Picture (right) courtesy of CNES

OSCAR-4, 1965-108C.

Radio amateur satellite launched on Titan IIIC launcher into too low an orbit, 29,120x168km inclined at 26 degrees, piggyback with three USAF satellites on the 21st December 1965 at 1400UTC from Cape Kennedy. It functioned until the 16th March 1966. It weighed 18.1kg with four monopole antennas, and carried a 144/431MHz transponder.
Picture (right) courtesy of AMSAT  

 

D-1A (Diapason-1) 1966-13A

Launched on a Diamant launcher from Hammaguir in Algeria on the 17 February 1966. The French satellite D-1A weighed 20kg, and was placed into a 504x2753km orbit inclined at 34 degrees. The French satellite mission was to carry out geodetic research.
Picture (right) courtesy of CNES

 

Pageos.

A 56.75kg PAssive GEOS reflector was launched alongside by a Thor Agena rocket from Vandenberg AFB on the 24th June 1966, and was tracked photographically to measure small perturbations in the Earth's gravitational field. It is a 84 faceted sphere, 30m in diameter. It disintegrated on 20th January 1976 for unknown reasons.

 

INTELSAT-2 F1 (Lani Bird)

Commercial communications satellite built by Hughes, and launched on the 26th October 1966 on a Delta DSV-3E launcher. The satellite was cylindrical in shape, measuring 1.42m diameter and 673mm in height, and weighed 87kg (162kg at launch). The satellite was operated by COMSAT in co-operation with the International Telecommunication Satellite Consortium (INTELSAT), and provided 240 telephone channels and operated at 125MHz.

 

GGTS (IDSCD), 1966-053A

A microsatellites for a gravity gradient test with two deployed booms launched on the 16th June 1966 on a Titan IIIC from the Eastern Test Range. The spacecraft weighs 47kg.

 

DSCS (IDSCD) , 1966-053B-H

A series of 26 microsatellites weighing 45kg launched between 16th June 1966 and 13th June 1968 for the U.S. DOD and managed by the USAF. A Titan IIIC was used from the Eastern Test Range. The Defence Satellite Communications System is referred to as 'discus', and provides strategic communication services, offering single channel communications of voice and data. The satellite is polygon shaped with 26 facets, and measures 0.85m diameter. The satellites were developed by TRW Inc. The life span was 18 months, but the original DSCS-1 was still operational in 1982.

 

INTELSAT-2 F2.

Commercial communications satellite built by Hughes, and launched on the 11th January 1967 on a Delta DSV-3E launcher. The satellite was similar to INTELSAT-2 F1.

 

DSCS (IDSCD) , 1967-003A-H

A series of 26 microsatellites weighing 45kg launched between 16th June 1966 and 13th June 1968 for the U.S. DOD and managed by the USAF. A Titan IIIC was used from the Eastern Test Range. The Defence Satellite Communications System is referred to as 'discus', and provides strategic communication services, offering single channel communications of voice and data. The satellite is polygon shaped with 26 facets, and measures 0.85m diameter. The satellites were developed by TRW Inc. The life span was 18 months, but the original DSCS-1 was still operational in 1982.

 

D-1C (Diademe 1) 1967-011A

The French 22.6kg microsat D-1C was launched on the 8th February 1967 on a Diamant launcher from Hammaguir into a 580x1340km orbit inclined at 40 degrees. The satellite was used to carry out geodetic research using Doppler data and photographs.
Picture (right) courtesy of CNES

 

D-1D (Diademe 2) 1967-014A.

D-1D was launched a week following the launch of its sister spacecraft Diademe 1 on the 15th February 1967 on a Diamant launcher from Hammaguir, into a 592x1886km orbit inclined at 39 degrees. The 22.6kg French satellite was used to carry out geodetic research. It provided laser and Doppler data for three months.
Picture (right) courtesy of CNES

INTELSAT-2 F3.

Commercial communications satellite built by Hughes, and launched on the 23rd March 1967 on a Delta DSV-3E launcher. The satellite was similar to INTELSAT-2 F1.

 

Ariel-3 .

Ariel-3, a 90kg microsatellite was launched from Vandenberg AFB on a Scout on the 5th May 1967 into a 498x606km 80 degree inclined orbit. The first all-British satellite measured radio noise from lightning, and galactic sources at frequencies that do not penetrate to the Earth's surface. It was spin-stabilised, and operated over more than two years. It re-entered in December 1970.

 

DSCS (IDSCD) , 1967-066A-D

A series of 26 microsatellites weighing 45kg launched between 16th June 1966 and 13th June 1968 for the U.S. DOD and managed by the USAF. A Titan IIIC was launched on the 1st July 1967 from the Eastern Test Range carrying 4 spacecraft. The Defence Satellite Communications System is referred to as 'discus', and provides strategic communication services, offering single channel communications of voice and data. The satellite is polygon shaped with 26 facets, and measures 0.85m diameter. The satellites were developed by TRW Inc. The fourth spacecraft (IDSCS/DATS ,066D) carried an electrically despun antenna.

 

INTELSAT-2 F4.

Commercial communications satellite built by Hughes, and launched on the 28th September 1967 on a Delta DSV-3E launcher. The satellite was similar to INTELSAT-2 F1.

 

WRESAT-1

WRESAT, built within 11 months by the Australian Weapons Research Establishment was launched by a Sparta launcher from Woomera on the 29th November 1967 into a 106x777km orbit inclined at 83deg. The 45kg Australian microsatellite used a modified American Redstone rocket and transmitted for 5 days, and re-entered after 42 days. (picture of spacecraft under construction).  More:...
[Australian Space site]

 

ESRO-II (IRIS)

A 75kg micro-satellite built by ESTEC for ESA, and launched on the 17th May 1968 from the Western Test Range California, on a SCOUT launcher. The orbit has a 1094km apogee and 332km perigee, inclined at 97.21 degrees (98.9min period). The satellite is cylindrical in shape with 760mm diameter and 850mm in height. Its primary mission was to study solar and galactic cosmic rays and particles with its 7 experiments. It re-entered the atmosphere on the 9th May 1971.

 

SECOR 10.

The 10th in the series of US army classified small spacecraft, SECOR or Sequential Collation of Range spacecraft, was launched unsuccessfully on the 18th May 1968 alongside Nimbus-B on a Thor AD/ Agena D launcher. The satellite was box shaped with dimensions 228 x 280 x 330mm, with eight antennas on the side and one on the top, weighing 20.4kg. It carried a 5.4kg solid state transponder to retransmit signals from four groundstations, allowing one of these stations to determine its position relative to the others. The SECOR system was the fore-runner of the DOD/USAF NAVSTAR GPS system.

 

DSCS (IDSCD) , 1968-050A-H

A series of 26 microsatellites weighing 45kg launched between 16th June 1966 and 13th June 1968 for the U.S. DOD and managed by the USAF. A Titan IIIC was used from the Eastern Test Range on the 13th June 1968. The Defence Satellite Communications System is referred to as 'discus', and provides strategic communication services, offering single channel communications of voice and data. The satellite is polygon shaped with 26 facets, and measures 0.85m diameter. The satellites were developed by TRW Inc. The life span was 18 months, but the original DSCS-1 was still operational in 1982.

 

ESRO-I AURORAE.

An 86kg micro-satellite launched on a SCOUT launcher from the Western Test Range California on the 3rd October 1968. Its mission was to study the polar ionosphere and auroral phenomena using 8 on-board experiments. It was built by ESTEC for ESA. The spacecraft is cylindrically shaped, with a height of 930mm and diameter of 760mm. It was launched into a 1534 x 254km orbit with an inclination of 93.76 degrees (103min period). It re-entered the atmosphere on the 26th June 1970.

 

SECOR 13.

The 13th in the series of US army classified small spacecraft was launched on the 14th April 1969 alongside Nimbus-C on a Thor AD/ Agena D launcher.

 

ESRO-I BOREAS.

A micro-satellite (86kg?) launched on a SCOUT launcher from the Western Test Range California on the 1st October 1969. The satellite is almost identical to ESRO-I/AURORAE, and performed similar measurements simultaneously with its sister spacecraft. It was built by ESTEC for ESA. The spacecraft is cylindrically shaped, with a height of 930mm and diameter of 760mm. It was launched into a 393 x 306 km orbit with an inclination of 85.12 degrees (91min period). It re-entered the atmosphere on the 23rd November 1969.

 

Azur (GRS-A, Research satellite 625A)

Azur is a 72.6kg German microsatellite developed by Bölkow KG in Ottobrun for BMwF/GfW, launched on a Scout from Vandenberg AFB on the 8th November 1969, into a 387x3150km sun-synchronous orbit inclined at 102.975 degrees. Seven experiments were employed to study the Earth's radiation environment, and solar particle fluxes. In particular proton flux density was measured. The program was carried out in co-operation with the United States to augment data gathered by the US explorer and OSO satellites. The spacecraft failed on the 29th July 1970.