22:
210:
299:
to take a series of photographs of its surface. The final stage of the project, E-4, was to be a nuclear strike on the Moon, as a display of force. As with the
American plan, the E series of projects was canceled while still in its planning stages, due to concerns regarding the safety and reliability
264:
in 1945 had a yield of 13–18 kilotons. The W25 would be carried by a rocket toward the shadowed side of the Moon where it would detonate on impact. The dust cloud resulting from the explosion would be lit by the Sun and therefore visible from Earth. According to
Reiffel, the Air Force's progress in
294:
Later reports in the 2010s showed that a corresponding Soviet project did indeed exist, although the only official documents on the project found so far began in 1958, not the 1957 date of the "anonymous" source whose rumors initiated the US project. The official Soviet plan also differs from the
101:
was part of the team responsible for predicting the effects of a nuclear explosion in vacuum and low gravity, and evaluating the scientific value of the project. The relevant documents remained secret for nearly 45 years and, despite
Reiffel's revelations, the United States government has never
385:
highlighted the discovery of the leaked information. That led
Reiffel to break his anonymity and write a letter to the journal confirming that Sagan's activity had at the time been considered a breach of the confidentiality of the project. Reiffel took the opportunity to reveal details of the
343:
Moon mission. In
December of that year, Apollo scientist Gary Latham suggested detonating a "smallish" nuclear device on the Moon in order to facilitate research into its geological make-up. The idea was dismissed because it would interfere with plans to measure the Moon's natural background
347:
The existence of
Project A119 remained largely secret until the mid-1990s, when writer Keay Davidson discovered the story while researching the life of Carl Sagan for a biography. Sagan's involvement with the project was apparent from his application for an academic scholarship at the
170:, began studying the effects of nuclear explosions on the environment. Those studies continued until 1962. In May 1958, ARF began covertly researching the potential consequences of a nuclear explosion on the Moon. The main objective of the program, running under the auspices of the
386:
studies, and his statements were widely reported in the media. Reiffel's revelation of the project was accompanied by his denunciation of the work carried out, with the scientist noting that he was "horrified that such a gesture to sway public opinion was ever considered".
356:, in 1959. In the application, Sagan gave details of the project research, which Davidson felt constituted a violation of national security. The leak consisted of Sagan revealing the titles of two classified papers from the A119 project — the 1958 paper
277:
The project was canceled by the Air Force in
January 1959, seemingly out of fear of the risk to the population if anything went wrong with the launch. Another factor, cited by project leader Leonard Reiffel, was the possible problem of
177:
At the time of the project's conception, newspapers were reporting a rumor that the Soviet Union was planning to detonate a hydrogen bomb on the Moon. According to press reports in late 1957, an anonymous source had divulged to a
295:
scenario reported in the press. Started in
January 1958, it was part of a series of proposals under the codename "E". Project E-1 entailed plans to reach the Moon, while projects E-2 and E-3 involved sending a probe around the
244:
for the project, but the United States Air Force vetoed that idea due to the weight of such a device, because it would be too heavy to be propelled by the missile which would have been used. It was then decided to use a
142:" by the media and was the impetus for the beginning of the Space Race. Trying to reclaim lost ground, the United States embarked on a series of new studies and projects, which eventually included the launch of
86:. An identical project by the Soviet Union (Project E-4) also never came to fruition due to fears of the warhead falling back on Soviet territory, and the potential for an international incident.
229:
in
Chicago to study the potential visibility of the explosion, the benefits to science, and the implications for the lunar surface. Among the members of the research team were astronomer
194:—Project A119 would also consider this boundary as the target for an explosion. It was also reported that a failure to hit the Moon would likely result in the missile returning to Earth.
201:, the "father of the H-bomb", who, in February 1957, proposed the detonation of nuclear devices both on and some distance from the lunar surface to analyze the effects of the explosion.
174:
which had initially proposed it, was to cause a nuclear explosion that would be visible from Earth. It was hoped that such a display would boost the morale of the
American people.
316:
in 1967 prevented future investigation of the concept of detonating a nuclear device on the Moon. By that time, both the United States and the Soviet Union had performed several
237:. Sagan was responsible for the mathematical projection of the expansion of a dust cloud in space around the Moon, an essential element in determining its visibility from Earth.
1050:
407:, a nuclear historian from the United Kingdom, has called the project's proposals "obscene", adding, "had they gone ahead, we would never have had the romantic image of
397:
was made public, over 40 years after its inception. A search for the other volumes of documentation revealed that other reports were destroyed in the 1980s by the
82:
would undoubtedly be a more popular achievement in the eyes of the American and international public alike. If executed, the plan might have led to a potential
661:
1216:
581:
825:
771:
706:
483:
1211:
134:
was the first artificial satellite in orbit around the Earth, and the surprise of its successful launch, compounded by the resounding failure of
1201:
1196:
390:
78:
The project was never carried out, being cancelled after "Air Force officials decided its risks outweighed its benefits", and because a
445:
943:
369:
1058:
1177:
1146:
1120:
1093:
1054:
353:
266:
671:
829:
339:
By 1969, the United States had succeeded in being the first nation to land a man on the moon with the success of the
1206:
398:
226:
167:
358:
Possible Contribution of Lunar Nuclear Weapons Detonations to the Solution of Some Problems in Planetary Astronomy
317:
309:
571:
333:
508:
Dörries, Matthias (2011). "The Politics of Atmospheric Sciences: "Nuclear Winter" and Global Climate Change".
833:
179:
696:
895:
867:
743:
187:
604:
475:
872:
283:
372:. These were among the eight reports created by the project, all of which were destroyed in 1987.
21:
748:
171:
83:
40:
798:
241:
163:
246:
59:, the flash of explosive light would have been faintly visible to people on Earth with their
1139:
Critical Assembly: A Technical History of Los Alamos During the Oppenheimer Years, 1943–1945
979:
900:
321:
296:
253:
8:
983:
518:(1). University of Chicago Press, on behalf of The History of Science Society: 198–223.
453:
190:. News reports of the rumored launch included mention of targeting the dark side of the
1134:
666:
543:
527:
329:
313:
214:
191:
183:
427:—A NASA project which used a kinetic impact to study the presence of water on the Moon
1173:
1152:
1142:
1116:
1089:
1032:
947:
701:
535:
547:
1165:
1130:
1022:
1013:
987:
970:
802:
609:
519:
510:
381:
368:, credited to I. Filosofo, was also named by Sagan in a 1961 paper written for the
349:
135:
1109:
89:
The existence of the US project was revealed in 2000 by a former executive at the
325:
279:
222:
94:
63:. This was meant as a show of force resulting in a possible boosting of domestic
51:, which would help in answering some of the mysteries in planetary astronomy and
721:
408:
250:
139:
772:"Secret Documents Reveal the Soviet Union Planned a Nuclear Blast on the Moon"
1190:
230:
198:
1156:
67:
in the capabilities of the United States, a boost that was needed after the
1036:
951:
576:
539:
115:
79:
68:
56:
52:
44:
404:
138:
to launch an American satellite after two attempts, had been dubbed the "
1104:
935:
257:
234:
143:
119:
98:
72:
1009:"Sagan breached security by revealing US work on a lunar bomb project"
531:
1027:
1008:
362:
Radiological Contamination of the Moon by Nuclear Weapons Detonations
340:
261:
182:
agent that the Soviets planned to commemorate the anniversary of the
123:
60:
776:
523:
111:
992:
965:
393:
request was lodged concerning Project A119. It was only then that
803:"The original E-3 project – exploding a nuclear bomb on the Moon"
146:, the creation of the Defense Advanced Research Projects Agency (
55:. If the explosive device detonated on the surface, and not in a
249:
warhead, a small, lightweight warhead with a relatively low 1.7
638:
636:
634:
632:
630:
628:
424:
64:
1129:
727:
379:, was published in 1999. Shortly after, a review published in
209:
186:
by causing a nuclear explosion on the Moon to coincide with a
147:
625:
916:
479:
449:
389:
As a result of the publicity the correspondence created, a
151:
90:
48:
662:"U.S. Planned Nuclear Blast on the Moon, Physicist Says"
1170:
Lunar Exploration: Human Pioneers and Robotic Surveyors
282:
which would affect future lunar research projects and
102:
officially acknowledged its involvement in the study.
896:"Scientist Withdraws Plans for Nuclear Blast on Moon"
860:
213:
The explosion was intended to occur along the Moon's
848:
91:
National Aeronautics and Space Administration (NASA)
16:
American plan to detonate a nuclear bomb on the Moon
888:
1108:
395:A Study of Lunar Research Flights – Volume I
289:
39:, was a top-secret plan developed in 1958 by the
1188:
269:would have made such a launch feasible by 1959.
738:
736:
596:
572:"US planned one big nuclear blast for mankind"
1102:
1088:(illustrated ed.). Infobase Publishing.
1051:"A Study of Lunar Research Flights, Volume I"
922:
1217:Nuclear weapons program of the United States
1163:
733:
642:
27:A Study of Lunar Research Flights – Volume I
97:, who had led the project in 1958. A young
43:. The aim of the project was to detonate a
791:
752:. Associated Press. 18 May 2000. p. 7
565:
563:
561:
559:
557:
468:
1026:
991:
438:
797:
503:
501:
366:Cosmic Radiation and Lunar Radioactivity
240:Scientists initially considered using a
208:
20:
1133:; Henriksen, Paul W.; Meade, Roger A.;
1006:
1000:
957:
944:United States National Research Council
697:"U.S. Weighed A-Blast on Moon in 1950s"
569:
554:
507:
370:United States National Research Council
197:A similar idea had been put forward by
1212:Military projects of the United States
1189:
1083:
964:Chyba, Christopher (28 October 1999).
854:
823:
1202:Deterrence theory during the Cold War
1197:Cold War history of the United States
963:
934:
691:
689:
659:
655:
653:
651:
605:"Latest Red Rumor: They'll Bomb Moon"
602:
498:
260:bomb dropped on the Japanese city of
1055:Defense Technical Information Center
1043:
826:"Russia wanted nuclear bomb on moon"
744:"U.S. considered lunar a-bomb blast"
217:, for maximum visibility from Earth.
817:
603:Myler, Joseph L (1 November 1957).
446:"50th Anniversary of the Space Age"
267:intercontinental ballistic missiles
13:
686:
648:
584:from the original on 20 March 2021
486:from the original on 18 March 2021
411:taking 'one giant leap for mankind
354:University of California, Berkeley
14:
1228:
709:from the original on 4 April 2019
705:. Associated Press. 18 May 2000.
37:A Study of Lunar Research Flights
660:Broad, William J (16 May 2000).
399:Illinois Institute of Technology
318:high-altitude nuclear explosions
227:Illinois Institute of Technology
168:Illinois Institute of Technology
1007:Reiffel, Leonard (4 May 2000).
966:"An exobiologist's life search"
928:
764:
570:Barnett, Antony (14 May 2000).
310:Partial Nuclear Test Ban Treaty
303:
272:
1141:. Cambridge University Press.
876:. 21 December 1969. p. 19
290:Evidence of the Soviet project
1:
1077:
105:
824:Tanner, Adam (9 July 1999).
431:
180:United States Secret Service
7:
940:Organic Matter and the Moon
904:. 7 January 1970. p. 7
418:
204:
188:lunar eclipse on 7 November
10:
1233:
221:A ten-member team, led by
164:Armour Research Foundation
157:
71:took an early lead in the
1084:Angelo, Joseph A (2007).
923:Davidson & Sagan 1999
873:The Sydney Morning Herald
375:The resulting biography,
320:, including the American
233:and his doctoral student
643:Ulivi & Harland 2004
1207:Exploration of the Moon
799:Zheleznyakov, Aleksandr
749:Pittsburgh Post-Gazette
300:of the launch vehicle.
225:, was assembled at the
172:United States Air Force
84:militarization of space
41:United States Air Force
1166:Harland, David Michael
1135:Westfall, Catherine L.
391:freedom of information
364:. A 1958 paper titled
218:
29:
360:, and the 1959 paper
212:
118:took the lead in the
24:
901:St. Petersburg Times
728:Hoddeson et al. 1993
456:on 16 September 2011
322:Operation Hardtack I
297:far side of the Moon
166:(ARF), based at the
984:1999Natur.401..857C
730:, pp. 392–393.
476:"Space Exploration"
308:The signing of the
265:the development of
256:. By contrast, the
122:with the launch of
1111:Carl Sagan: A Life
836:on 24 October 2012
830:Independent Online
667:The New York Times
377:Carl Sagan: A Life
330:Operation Fishbowl
314:Outer Space Treaty
219:
184:October Revolution
30:
1179:978-1-85233-746-9
1148:978-0-521-54117-6
1131:Hoddeson, Lillian
1122:978-0-471-25286-3
1095:978-0-8160-5775-7
1086:Human Spaceflight
978:(6756): 857–858.
702:Los Angeles Times
645:, pp. 19–21.
480:National Archives
332:, and the Soviet
284:Moon colonization
1224:
1183:
1160:
1126:
1114:
1103:Davidson, Keay;
1099:
1071:
1070:
1068:
1066:
1061:on 18 April 2012
1057:. Archived from
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1041:
1040:
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1028:10.1038/35011148
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832:. Archived from
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759:
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683:
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670:. Archived from
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646:
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623:
622:
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610:Pittsburgh Press
600:
594:
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591:
589:
567:
552:
551:
505:
496:
495:
493:
491:
472:
466:
465:
463:
461:
452:. Archived from
442:
414:
350:Miller Institute
312:in 1963 and the
136:Project Vanguard
129:
35:, also known as
1232:
1231:
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1226:
1225:
1223:
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1221:
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444:
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421:
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326:Operation Argus
306:
292:
280:nuclear fallout
275:
223:Leonard Reiffel
207:
160:
127:
108:
95:Leonard Reiffel
17:
12:
11:
5:
1230:
1220:
1219:
1214:
1209:
1204:
1199:
1185:
1184:
1178:
1164:Ulivi, Paolo;
1161:
1147:
1127:
1121:
1100:
1094:
1079:
1076:
1073:
1072:
1042:
999:
956:
946:, p. 46,
927:
915:
887:
868:"Moon madness"
859:
847:
816:
790:
763:
732:
720:
685:
674:on 21 May 2008
647:
624:
595:
553:
524:10.1086/661272
497:
467:
436:
435:
433:
430:
429:
428:
420:
417:
409:Neil Armstrong
305:
302:
291:
288:
274:
271:
206:
203:
159:
156:
140:Sputnik crisis
130:October 1957.
107:
104:
15:
9:
6:
4:
3:
2:
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1218:
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1118:
1113:
1112:
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1101:
1097:
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1081:
1060:
1056:
1052:
1046:
1038:
1034:
1029:
1024:
1020:
1016:
1015:
1010:
1003:
994:
993:10.1038/44716
989:
985:
981:
977:
973:
972:
967:
960:
953:
949:
945:
941:
937:
931:
925:, p. 95.
924:
919:
903:
902:
897:
891:
875:
874:
869:
863:
857:, p. 28.
856:
851:
835:
831:
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804:
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794:
779:
778:
773:
767:
751:
750:
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739:
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724:
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252:
248:
243:
242:hydrogen bomb
238:
236:
232:
231:Gerard Kuiper
228:
224:
216:
211:
202:
200:
199:Edward Teller
195:
193:
189:
185:
181:
175:
173:
169:
165:
162:In 1949, the
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50:
46:
42:
38:
34:
28:
23:
19:
1172:. Springer.
1169:
1138:
1110:
1085:
1063:. Retrieved
1059:the original
1045:
1021:(6782): 13.
1018:
1012:
1002:
975:
969:
959:
939:
930:
918:
906:. Retrieved
899:
890:
878:. Retrieved
871:
862:
850:
838:. Retrieved
834:the original
819:
807:. Retrieved
805:. Sven Grahn
793:
781:. Retrieved
775:
766:
754:. Retrieved
747:
723:
711:. Retrieved
700:
676:. Retrieved
672:the original
665:
615:. Retrieved
613:. p. 13
608:
598:
586:. Retrieved
577:The Guardian
575:
515:
509:
488:. Retrieved
470:
458:. Retrieved
454:the original
440:
403:
394:
388:
380:
376:
374:
365:
361:
357:
346:
338:
307:
304:Consequences
293:
276:
273:Cancellation
239:
220:
196:
176:
161:
131:
116:Soviet Union
109:
88:
80:Moon landing
77:
69:Soviet Union
57:lunar crater
53:astrogeology
45:nuclear bomb
36:
33:Project A119
32:
31:
26:
18:
1105:Sagan, Carl
1065:9 September
936:Sagan, Carl
908:9 September
880:9 September
855:Angelo 2007
840:9 September
809:9 September
756:9 September
713:9 September
678:9 September
617:9 September
588:8 September
460:8 September
405:David Lowry
344:radiation.
110:During the
1191:Categories
1078:References
783:18 January
258:Little Boy
235:Carl Sagan
215:terminator
192:terminator
144:Explorer 1
120:Space Race
106:Background
99:Carl Sagan
73:Space Race
1115:. Wiley.
432:Footnotes
341:Apollo 11
334:Project K
262:Hiroshima
124:Sputnik 1
61:naked eye
25:Cover of
1168:(2004).
1157:26764320
1137:(1993).
1107:(1999).
1037:10811192
938:(1961),
777:Novinite
707:Archived
582:Archived
548:23719340
540:21936194
490:24 March
484:Archived
419:See also
205:Research
112:Cold War
980:Bibcode
952:1335482
352:of the
251:kiloton
158:Project
150:), and
132:Sputnik
47:on the
1176:
1155:
1145:
1119:
1092:
1035:
1014:Nature
971:Nature
950:
546:
538:
532:661272
530:
511:Osiris
425:LCROSS
382:Nature
128:
114:, the
65:morale
544:S2CID
528:JSTOR
254:yield
148:DARPA
1174:ISBN
1153:OCLC
1143:ISBN
1117:ISBN
1090:ISBN
1067:2011
1033:PMID
948:OCLC
910:2011
882:2011
842:2011
811:2011
785:2021
758:2011
715:2011
680:2011
619:2011
590:2011
536:PMID
492:2021
462:2011
450:NASA
152:NASA
126:on 4
49:Moon
1023:doi
1019:405
988:doi
976:401
520:doi
415:".
247:W25
1193::
1151:.
1053:.
1031:.
1017:.
1011:.
986:.
974:.
968:.
942:,
898:.
870:.
828:.
801:.
774:.
746:.
735:^
699:.
688:^
664:.
650:^
627:^
607:.
580:.
574:.
556:^
542:.
534:.
526:.
516:26
514:.
500:^
482:.
478:.
448:.
401:.
336:.
328:,
324:,
286:.
154:.
93:,
75:.
1182:.
1159:.
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