Listed are all launches, irrespective of outcome, that were irretrievably committed to flight towards orbit or intended to accelerate the payload to escape velocity.

Launch times are in UTC and are from the launching agency or estimated by 'walking back' along the ground track to the launch site. The PRIME source of orbit data and decay information is SpaceTrack. A minority of orbits is based on amateur observations using visual and radio techniques. Occasionally, early orbit data are published by satellite owners and may cover periods before SpaceTrack lists a new object. In extreme cases, orbits are estimated from public data.

Apogee and perigee are measured against the Earth's mean equatorial radius - 6378.145 km. Care should be exercised when comparing with other published orbits even when the source is shown as SpaceTrack.

Combined Venus exploration craft and final rocket stage, left in LEO when the rocket stage failed to fire. The Spacecraft remained attached to the rocket. Catalogued by NORAD as Sputnik 7.

epoch (UTC)

s-m axis( km )

ecc

perigee( km )

apogee( km )

period( min )

incl ( ° )

ω ( ° )

1961 Feb 5, 11:39

6645

0.0070

220

313

89.84

65.10

27

1961-003

Molniya 8K78Baikonur Cosmodrome, Kazakhstan

1961 Feb 12, 00:34

Venera (1VA № 2)1961 γ180

in space

Venus exploration spacecraft. It passed close to Venus around 1961 Jun 2 but radio communication had ceased 1961 Feb 17.

In heliocentric orbit

1961-004

Scout X-1Wallops Flight Facility, Virginia, USA

1961 Feb 16, 13:05

Explorer 9 (S-56A)1961 δ 181

Re-entered 1964 Apr 9

Science satellite for atmospheric density measurements- part of the payload was a 4m diameter balloon. Replacement for satellite lost 1960 Dec 4.

epoch (UTC)

s-m axis( km )

ecc

perigee( km )

apogee( km )

period( min )

incl ( ° )

ω ( ° )

1961 Feb 16, 14:42

7992

0.1224

636

2592

118.50

38.63

99

1961-005

Thor Agena BVandenberg AFB, California, USA

1961 Feb 17, 20:25

Discoverer 20 (Corona 9014A/KH-5)1961 ε 183

Re-entered 1962 Jul 28

US film recovery reconnaissance satellite. Re-entry vehicle did not separate.

epoch (UTC)

s-m axis( km )

ecc

perigee( km )

apogee( km )

period( min )

incl ( ° )

ω ( ° )

1961 Feb 18, 05:25

6914

0.0364

284

787

95.35

80.91

124

1961-006

Thor Agena BVandenberg AFB, California, USA

1961 Feb 18, 22:58

Discoverer 21 (Corona RM-2)1961 ζ 184

Re-entered 1962 Apr 20

Instrumented Agena-B rocket stage testing sensors for the MIDAS missile early warning satellite programme. Also used to demonstrate the Agena re-start capability.

epoch (UTC)

s-m axis( km )

ecc

perigee( km )

apogee( km )

period( min )

incl ( ° )

ω ( ° )

1961 Feb 18, 23:58

7032

0.0589

239

1068

97.81

80.74

141

1961-007

Thor AblestarCape Canaveral AFS, Florida, USA

1961 Feb 22, 03:45

Transit 3B/LOFTI1961 η 187

Re-entered 1961 Mar 30

Experimental navigation satellite. The LOFTI (Low Frequency Trans-Ionospheric) satellite failed to separate from Transit. It was used for experiments in the possibility of using LF radio to communicate with submerged submarines but two of the LF aerials could not be deployed.

epoch (UTC)

s-m axis( km )

ecc

perigee( km )

apogee( km )

period( min )

incl ( ° )

ω ( ° )

1961 Feb 22, 05:03

6965

0.0571

189

984

96.41

28.38

33

Failed to reach orbit

Juno IICape Canaveral AFS, Florida, USA

1961 Feb 25, 00:13

Explorer (S-45)

Science satellite for ionosphere research. Lost when the launch vehicle failed.

1961-008

Vostok 8K72KBaikonur Cosmodrome, Kazakhstan

1961 Mar 9, 06:29

Korabl Sputnik 4 (Vostok-3 №1)1961 θ 191

Re-entered 1961 Mar 9Recovered

Carried a dog - Chernushka, and the instrumented mannequin 'Ivan Ivanovich' plus other biological specimens. The mannequin was ejected from the capsule and landed by parachute. Chernushka landed inside the cabin.

epoch (UTC)

s-m axis( km )

ecc

perigee( km )

apogee( km )

period( min )

incl ( ° )

ω ( ° )

1961 Mar 9, 07:48

6545

0.0070

121

213

87.83

64.93

95

1961-009

Vostok 8K72KBaikonur Cosmodrome, Kazakhstan

1961 Mar 25, 05:54

Korabl Sputnik 5 (Vostok-3 №2)1961 ι 195

Re-entered 1961 Mar 25Recovered

Carried a dog - Zvezdochka, and the instrumented mannequin 'Ivan Ivanovich' on it's second flight. The mannequin was ejected from the capsule and landed by parachute. Zvezdochka landed inside the cabin.

epoch (UTC)

s-m axis( km )

ecc

perigee( km )

apogee( km )

period( min )

incl ( ° )

ω ( ° )

1961 Mar 25, 05:53

6574

0.0050

163

229

88.42

64.90

60

1961-010

Thor DeltaCape Canaveral AFS, Florida, USA

1961 Mar 25, 15:17

Explorer 10 (P-14)1961 κ 198

Re-entered 1961 Jun 30

Science satellite to investigate the magnetic field between the Earth and Moon. Barycentric trajectory equated to an orbit approx 150 x 215,000 km at 32° inclination.

In barycentric orbit

Failed to reach orbit

Thor Agena BVandenberg AFB, California, USA

1961 Mar 30, 20:34

Discoverer 22 (Corona 9015/KH-2)

US film recovery reconnaissance satellite. Satellite lost when upper stage of the launch vehicle failed.

1961-011

Thor Agena BVandenberg AFB, California, USA

1961 Apr 8, 19:21

Discoverer 23 (Corona 9016A/KH-5)1961 λ 1100

Re-entered 1962 Apr 16

US film recovery reconnaissance satellite. Re-entry vehicle boosted to a higher orbit when stabilisation of the main vehicle failed.

epoch (UTC)

s-m axis( km )

ecc

perigee( km )

apogee( km )

period( min )

incl ( ° )

ω ( ° )

1961 Apr 8, 23:30

6850

0.0258

295

648

94.03

82.31

168

1961-012

Vostok 8K72KBaikonur Cosmodrome, Kazakhstan

1961 Apr 12, 06:07

Vostok (Vostok-3A №3)1961 μ 1103

Re-entered 1961 Apr 12Recovered

First piloted spaceflight for a single orbit of the Earth - carried Yuri Gagarin. Retro fire came 1961 Apr 12, 07:25 UTC. After re-entry, Gagarin was ejected from the cabin and landed under a separate parchute. The cabin used its own parachute system.

epoch (UTC)

s-m axis( km )

ecc

perigee( km )

apogee( km )

period( min )

incl ( ° )

ω ( ° )

1961 Apr 12, 06:00

6619

0.0110

168

314

89.33

64.95

60

Failed to reach orbit

Atlas DCape Canaveral AFS, Florida, USA

1961 Apr 25, 16:15

Mercury (MA-3)

Single orbit mission of the Mercury spacecraft to verify the launching system and the retro-fire, re-entry and recovery sequence. It failed when Range Safety destroyed the launch vehicle but the Mercury Launch Escape System meant that the spacecraft was recovered intact.

1961-013

Juno IICape Canaveral AFS, Florida, USA

1961 Apr 27, 14:16

Explorer 11 (S-15)1961 ν 1107

in space

Science satellite for Gamma ray astronomy.

epoch (UTC)

s-m axis( km )

ecc

perigee( km )

apogee( km )

period( min )

incl ( ° )

ω ( ° )

1961 Apr 28, 07:53

7514

0.0846

501

1772

108.04

28.80

125

Failed to reach orbit

Juno IICape Canaveral AFS, Florida, USA

1961 May 24, 19:48

Explorer (S-45A)

Science satellite for ionosphere research. Lost when the launch vehicle failed.

Failed to reach orbit

Thor Agena BVandenberg AFB, California, USA

1961 Jun 8, 21:16

Discoverer 24 (Corona 9018A/KH-5)

US film recovery reconnaissance satellite. Lost when launch vehicle failed.

Navigation satellite. First satellite to carry a nuclear power source.

epoch (UTC)

s-m axis( km )

ecc

perigee( km )

apogee( km )

period( min )

incl ( ° )

ω ( ° )

1961 Jul 9, 06:00

7317

0.0080

880

998

103.82

66.81

289

GRAB 3/Injun 11961 ο 2117

in space

Pair of satellites that separated from Transit 4A but not from each other. GRAB 3 was a US Naval Laboratory satellite with a SIGINT mission. Injun was a USN satellite investigating radiation in the magnetosphere.

epoch (UTC)

s-m axis( km )

ecc

perigee( km )

apogee( km )

period( min )

incl ( ° )

ω ( ° )

1961 Jul 6, 08:47

7318

0.0078

882

997

103.83

66.82

288

Failed to reach orbit

Scout X-1Wallops Flight Facility, Virginia, USA

1961 Jun 30, 17:09

Explorer (S-55)

Science satellite launched to evaluate the Scout launch vehicle and to investigate micrometeoroids. It was lost when the launch vehicle third stage failed to ignite.

Sytems test of a hard-impact lunar photographic spacececraft. The intention was to enter a highly elliptical orbit with apogee around 500,000 km, followed by re-entry into the atmosphere after about 50 days. It failed when the Agena upper stage shut down immediately on commencing its second burn, leaving the vehcle in LEO.

epoch (UTC)

s-m axis( km )

ecc

perigee( km )

apogee( km )

period( min )

incl ( ° )

ω ( ° )

1961 Aug 23, 11:07

6717

0.0248

172

506

91.31

32.93

199

1961-022

Scout X-1Wallops Flight Facility, Virginia, USA

1961 Aug 25, 18:29

Explorer 13 (S-55A)1961 χ 1180

Re-entered 1961 Aug 28

Science satellite for micrometeoroid research.

epoch (UTC)

s-m axis( km )

ecc

perigee( km )

apogee( km )

period( min )

incl ( ° )

ω ( ° )

1961 Aug 26, 18:13

6966

0.0320

365

810

96.43

36.42

275

1961-023

Thor Agena BVandenberg AFB, California, USA

1961 Aug 30, 20:00

Discoverer 29 (Corona 9023/KH-3)1961 ψ 1181

Re-entered 1961 Sep 10Recovered

US film recovery reconnaissance satellite. Re-entry vehicle recovered 1961 Sep 1 - all film frames were found to be out of focus.

epoch (UTC)

s-m axis( km )

ecc

perigee( km )

apogee( km )

period( min )

incl ( ° )

ω ( ° )

1961 Aug 31, 07:41

6724

0.0292

149

542

91.45

82.14

83

Failed to reach orbit

Atlas Agena BPoint Arguello, California, USA

1961 Sep 9, 19:28

SAMOS 3 (E2-1)

Satellite And Missile Obervation System - photographic reconnaissance satellite intended to return film in a re-entry vehicle. Lost when the launch vehicle exploded on the pad.

1961-024

Thor Agena BVandenberg AFB, California, USA

1961 Sep 12, 19:59

Discoverer 30 (Corona 9022/KH-3)1961 ω 1182

Re-entered 1961 Dec 11

US film recovery reconnaissance satellite. Re-entry vehicle recovered 1961 Sep 1 - all film frames were found to be out of focus (similar to Discoverer 29).

epoch (UTC)

s-m axis( km )

ecc

perigee( km )

apogee( km )

period( min )

incl ( ° )

ω ( ° )

1961 Sep 13, 13:56

6767

0.0250

220

558

92.34

82.58

142

1961-025

Atlas DCape Canaveral AFS, Florida, USA

1961 Sep 13, 14:04

Mercury (MA-4)1961 αα1183

Re-entered 1961 Sep 13Recovered

Single orbit mission of the Mercury spacecraft to verify the launching system and the retro-fire, re-entry and recovery sequence. Mission successful - Mercury spacecraft recovered after 109 minutes, at the end of a single circuit of the Earth.

epoch (UTC)

s-m axis( km )

ecc

perigee( km )

apogee( km )

period( min )

incl ( ° )

ω ( ° )

1961 Sep 13, 14:09

6573

0.0070

149

241

88.40

32.54

70

1961-026

Thor Agena BVandenberg AFB, California, USA

1961 Sep 17, 21:00

Discoverer 31 (Corona 9024/KH-3)1961 αβ1186

Re-entered 1961 Oct 26

US film recovery reconnaissance satellite. Re-entry vehicle not released due to a power failure 1961 Sep 9.

epoch (UTC)

s-m axis( km )

ecc

perigee( km )

apogee( km )

period( min )

incl ( ° )

ω ( ° )

1961 Sep 18, 07:04

6696

0.0127

233

403

90.89

82.70

146

1961-027

Thor Agena BVandenberg AFB, California, USA

1961 Oct 13, 19:22

Discoverer 32 (Corona 9025/KH-3)1961 αγ1189

Re-entered 1961 Nov 13Recovered

US film recovery reconnaissance satellite. Re-entry vehicle recovered 1961 Oct 14 - most film frames were found to be out of focus (as with both previous missions).

epoch (UTC)

s-m axis( km )

ecc

perigee( km )

apogee( km )

period( min )

incl ( ° )

ω ( ° )

1961 Oct 14, 02:24

6691

0.0118

234

392

90.78

81.69

158

1961-028

Atlas Agena BPoint Arguello, California, USA

1961 Oct 21, 13:53

MIDAS 41961 αδ1192

in space

Experimental satellite of the Missile Defense and Early Warning System equipped with infrared sensors and intended to work in conjunction with the land-based BMEWS system.

epoch (UTC)

s-m axis( km )

ecc

perigee( km )

apogee( km )

period( min )

incl ( ° )

ω ( ° )

desc nodelocal time

1961 Dec 17, 00:11

10004

0.0122

3504

3748

165.96

95.90

334

02:51

Failed to reach orbit

Thor Agena BVandenberg AFB, California, USA

1961 Oct 23, 19:23

Discoverer 33 (Corona 9026/KH-3)

US film recovery reconnaissance satellite. Satellite was lost when the launch vehicle failed.

Failed to reach orbit

Cosmos 63S1Kapustin Yar Cosmodrome, Volgograd Region, Russia

1961 Oct 27, 16:30

Cosmos (DS-1 № 1)

Technology test satellite. Lost when the launch vehicle failed to reach orbital velocity.

Failed to reach orbit

Blue Scout IICape Canaveral AFS, Florida, USA

1961 Nov 1, 15:32

Mercury-Scout 1

Small satellite to be used in testing the Project Mercury communications networ. Lost when the launch vehicle broke up after 26s.

1961-029

Thor Agena BVandenberg AFB, California, USA

1961 Nov 5, 20:00

Discoverer 34 (Corona 9027/KH-3)1961 αε1197

Re-entered 1962 Dec 7

US film recovery reconnaissance satellite. Guidance error at launch meant the orbit was too elliptical and re-entry vehicle recovery was not attempted.

epoch (UTC)

s-m axis( km )

ecc

perigee( km )

apogee( km )

period( min )

incl ( ° )

ω ( ° )

1961 Nov 7, 21:36

6994

0.0558

226

1006

97.01

82.52

145

1961-030

Thor Agena BVandenberg AFB, California, USA

1961 Nov 15, 21:23

Discoverer 35 (Corona 9028/KH-3)1961 αζ1201

Re-entered 1961 Dec 3Recovered

US film recovery reconnaissance satellite. Re-entry vehicle recovered 1961 Nov 16. Designation and catalogue number are out of sequence.

epoch (UTC)

s-m axis( km )

ecc

perigee( km )

apogee( km )

period( min )

incl ( ° )

ω ( ° )

1961 Nov 16, 04:20

6647

0.0054

233

304

89.89

81.63

140

1961-031

Thor AblestarCape Canaveral AFS, Florida, USA

1961 Nov 15, 22:26

Transit 4B1961 αη1202

in space

Navigation satellite with nuclear power source. Sustained damage from the electromagnetic pulse associated with the US "Starfish" high altitude nuclear test 1963 Jul 9. Designation and catalogue number are out of sequence.

epoch (UTC)

s-m axis( km )

ecc

perigee( km )

apogee( km )

period( min )

incl ( ° )

ω ( ° )

1961 Nov 19, 13:53

7409

0.0129

936

1127

105.79

32.42

1

Traac1961 αη2205

in space

Tethered satellite experiment - the main body was attached to a mass at the end of a boom and a spring wire. Also carried detectors to measure protons and heavier particles in the van Allen Radiation Belt.

epoch (UTC)

s-m axis( km )

ecc

perigee( km )

apogee( km )

period( min )

incl ( ° )

ω ( ° )

1961 Nov 22, 12:20

7410

0.0131

935

1129

105.80

32.43

25

1961-032

Atlas Agena BCape Canaveral AFS, Florida, USA

1961 Nov 18, 08:12

Ranger 2 (P-33/RA-2)1961 αθ206

Re-entered 1961 Nov 20

Sytems test of a hard-impact lunar photographic spacececraft. The intention was to enter a highly elliptical orbit with apogee around 500,000 km. It failed when the Agena failed to ignite for its second burn, leaving the vehcle in LEO.

epoch (UTC)

s-m axis( km )

ecc

perigee( km )

apogee( km )

period( min )

incl ( ° )

ω ( ° )

1961 Nov 18, 09:15

6576

0.0073

149

246

88.45

33.34

49

Failed to reach orbit

Atlas Agena BPoint Arguello, California, USA

1961 Nov 22, 20:45

SAMOS 4 (E5-1)

Satellite And Missile Obervation System - photographic reconnaissance satellite intended to return film in a re-entry vehicle. Lost when the Agena stage failed to ignite.

1961-033

Atlas DCape Canaveral AFS, Florida, USA

1961 Nov 29, 15:07

Mercury (MA-5)1961 αι1208

Re-entered 1961 Nov 29Recovered

Intended three orbit mission of the Mercury spacecraft carrying the chimpanzee "Enos". Recovered early after two circuits, because of problems with the attitude control system. Landed 10:28 UTC in the Atlantic Ocean off Florida.

epoch (UTC)

s-m axis( km )

ecc

perigee( km )

apogee( km )

period( min )

incl ( ° )

ω ( ° )

1961 Nov 29, 15:12

6576

0.0061

158

238

88.45

32.63

70

Failed to reach orbit

Vostok 8K72KBaikonur Cosmodrome, Kazakhstan

1961 Dec 11, 09:39

Cosmos (Zenit-2 11Ф61 № 1)

Protoype recoverable photo-reconnaissance satellite - failed to reach orbit when the upper stage cutoff prematurely and the spacecraft destruct system fired at T+407 seconds. The descent module reportedly landed in Siberia but was never found.

1961-034

Thor Agena BVandenberg AFB, California, USA

1961 Dec 12, 20:40

Discoverer 36 (Corona 9029/KH-3)1961 ακ1213

Re-entered 1962 Mar 8Recovered

US film recovery reconnaissance satellite. Re-entry vehicle re-entered 1961 Dec 16 but the mid-air snatch was missed and it was kept afloat for several hours by frogmen.

epoch (UTC)

s-m axis( km )

ecc

perigee( km )

apogee( km )

period( min )

incl ( ° )

ω ( ° )

1961 Dec 13, 17:33

6740

0.0187

235

488

91.78

81.21

138

OSCAR 11961 ακ2214

in space

Orbiting Satellite Carrying Amateur Radio. First amateur radio satellite - transmitted the letters "HI" in morse code at an amateur frequency near 145 MHz for a period of 20 days.

epoch (UTC)

s-m axis( km )

ecc

perigee( km )

apogee( km )

period( min )

incl ( ° )

ω ( ° )

1961 Dec 15, 13:55

6735

0.0181

235

479

91.69

81.21

131

Failed to reach orbit

Cosmos 63S1Kapustin Yar Cosmodrome, Volgograd Region, Russia

1961 Dec 21, 12:30

Cosmos (DS-1 № 2)

Developmental satellite. Lost when the launch vehicle second stage failed to ignite.

1961-035

Atlas Agena BPoint Arguello, California, USA

1961 Dec 22, 19:12

SAMOS 5 (E5-2)1961 αλ2218

Re-entered 1961 Dec 31

Satellite And Missile Obervation System - photographic reconnaissance satellite intended to return film in a re-entry vehicle. Retro-fire failed and the satellite eventually decayed naturally.