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In spite of various hardware difficulties and the loss of Injun 2 due to an upper stage failure, the program was generally successful. In particular, they produced data on the
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to control spacecraft attitude. (The last in the series was spin-stabilized). Instruments included particle detectors of varying types,
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Swift, Daniel W.; Gurnett, Donald A. (1973). "Direct comparison between satellite electric field measurements and the visual aurora".
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The design specifics of the satellites had little in common, though all were solar-powered and the first five used
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Electrical Fields and Plasma
Observations in the Magnetosphere, in Critical Problems in Magnetospheric Physics
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This article incorporates text from this source, which is in the
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This article incorporates text from this source, which is in the
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This article incorporates text from this source, which is in the
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637:"IE D (Injun 6, Hawkeye, Neutral Point Explorer, Explorer 52)"
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to observe various radiation and magnetic phenomena in the
61:. The last three satellites were launched as part of the
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401:. American Geophyscial Union. pp. 123–138
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78:electrical convection in the magnetosphere
422:"The Effects of High Altitude Explosions"
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80:, and the radiation after effects of the
34:designed and built by researchers at the
94:
591:. Gunter's Space Page. 11 December 2017
575:. Gunter's Space Page. 11 December 2017
559:. Gunter's Space Page. 11 December 2017
339:
272:IE-D, Hawkeye, Neutral Point Explorer,
427:. NASA. NASA TN D-2402. Archived from
7:
639:. Gunter's Space Page. 8 April 2020
623:. Gunter's Space Page. 8 April 2020
607:. Gunter's Space Page. 8 April 2020
392:Gurnett, Donald. Dyer, E.R. (ed.).
1553:Derelict satellites orbiting Earth
692:List of Explorers Program missions
420:Hess, Wilmot N. (September 1964).
14:
1518:indicates active current missions
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349:Journal of Geophysical Research
1:
621:"IE C (Injun 5, Explorer 40)"
605:"IE B (Injun 4, Explorer 25)"
528:"IE C (Injun 5, Explorer 40)"
203:Deorbited on 25 August 1968.
1524:indicates cancelled missions
30:program was a series of six
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85:high-altitude nuclear test
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689:
74:Van Allen radiation belts
143:Failed to separate from
498:. NASA. 28 October 2021
496:"Explorer 25 (Injun 4)"
466:. NASA. 28 October 2020
369:10.1029/JA078i031p07306
47:magnetic stabilization
23:
21:
532:Gunter's Space Page
361:1973JGR....78.7306S
1563:University of Iowa
868:25 (Injun 4, IE-B)
434:on 11 October 2011
320:Spaceflight portal
243:IE-C, Explorer 40
147:; still in orbit.
36:University of Iowa
24:
1558:Explorers Program
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953:42 (Uhuru, SAS-A)
683:Explorers Program
355:(31): 7306–7313.
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110:Ceased operation
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515:public domain
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133:6 March 1963
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51:magnetometers
48:
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1516:Green titles
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1421:
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1362:82 (CHIPSat)
1306:
1299:
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1174:
943:40 (Injun 5)
942:
867:
838:S-66A (BE-A)
641:. Retrieved
625:. Retrieved
609:. Retrieved
593:. Retrieved
577:. Retrieved
561:. Retrieved
535:. Retrieved
531:
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500:. Retrieved
490:
468:. Retrieved
458:
436:. Retrieved
429:the original
415:
403:. Retrieved
394:
387:
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278:3 June 1974
71:
44:
42:and beyond.
27:
25:
15:
1522:Grey titles
1350:79 (HETE-2)
1266:93 (NuSTAR)
1241:81 (RHESSI)
1216:68 (SAMPEX)
1058:61 (Magsat)
1033:56 (ISEE-1)
923:36 (GEOS-B)
888:29 (GEOS-A)
298:Explorer 52
274:Explorer 52
213:Explorer 25
55:photometers
1547:Categories
1246:83 (GALEX)
1226:73 (TRACE)
1190:HelioSwarm
1141:84 (Swift)
1123:78 (IMAGE)
1008:53 (SAS-C)
993:50 (IMP-J)
988:49 (RAE-B)
983:48 (SAS-B)
978:47 (IMP-H)
968:45 (SSS-A)
958:43 (IMP-I)
948:41 (IMP-G)
933:38 (RAE-A)
918:35 (IMP-E)
913:34 (IMP-F)
908:33 (IMP-D)
898:31 (DME-A)
883:28 (IMP-C)
873:26 (EPE-D)
858:23 (S-55C)
848:21 (IMP-B)
828:18 (IMP-A)
818:16 (S-55B)
813:15 (EPE-C)
808:14 (EPE-B)
803:13 (S-55A)
798:12 (EPE-A)
713:Explorer 1
643:8 November
627:8 November
611:8 November
595:8 November
579:8 November
563:8 November
537:6 February
502:8 November
470:8 November
405:8 February
334:References
254:June 1971
189:Thor-Agena
76:including
40:ionosphere
32:satellites
1467:Proposals
1460:Proposals
1340:72 (SNOE)
1287:97 (IXPE)
1273:94 (IRIS)
1259:91 (IBEX)
1236:75 (WIRE)
1231:74 (SWAS)
1221:70 (FAST)
1169:96 (ICON)
1162:95 (TESS)
1155:92 (WISE)
1128:80 (WMAP)
1118:77 (FUSE)
1106:69 (RXTE)
1088:67 (EUVE)
1083:66 (COBE)
1068:63 (DE-2)
1063:62 (DE-1)
1053:60 (SAGE)
1043:58 (HCMM)
1018:55 (AE-E)
1013:54 (AE-D)
998:51 (AE-C)
938:39 (AD-C)
903:32 (AE-B)
878:27 (BE-C)
863:24 (AD-B)
853:22 (BE-B)
843:20 (IE-A)
833:19 (AD-A)
823:17 (AE-A)
783:11 (S-15)
768:9 (S-56A)
706:1958–1992
589:"Injun 3"
573:"Injun 2"
557:"Injun 1"
464:"Injun 1"
438:7 October
282:Scout X-4
250:Scout X-4
221:Scout X-4
161:Thor-Able
129:Thor-Able
104:Launched
1356:INTEGRAL
1252:90 (AIM)
1112:71 (ACE)
1078:65 (CCE)
1073:64 (SME)
1048:59 (ICE)
1038:57 (IUE)
973:46 (MTS)
748:7 (S-1A)
699:Missions
306:See also
269:Injun 6
240:Injun 5
208:Injun 4
180:Injun 3
152:Injun 2
145:Solrad 3
120:Injun 1
107:Vehicle
1528:Italics
1474:FINESSE
1423:SunRISE
1301:TRACERS
1176:SPHEREx
743:6 (S-2)
357:Bibcode
65:of the
59:auroras
1499:ESCAPE
1494:EXCEDE
1384:Hitomi
1372:Suzaku
1335:HETE-1
1028:DADE-B
1023:DADE-A
211:IE-B,
115:Notes
91:Launch
53:, and
1489:ASTRE
1484:OHMIC
1479:Arcus
1410:GUSTO
1404:XRISM
1390:NICER
1378:TWINS
1367:CINDI
1294:PUNCH
1098:MIDEX
788:S-45A
753:S-46A
432:(PDF)
425:(PDF)
399:(PDF)
98:Name
28:Injun
1437:CASE
1430:EZIE
1397:GOLD
1319:UNEX
1308:COSI
1280:GEMS
1208:SMEX
1197:UVEX
1183:MUSE
1134:FAME
793:S-55
773:S-45
763:S-56
645:2021
629:2021
613:2021
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565:2021
539:2022
504:2021
472:2021
440:2007
407:2015
67:NASA
26:The
1416:AWE
738:S-1
373:hdl
365:doi
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1327:I
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