The Vela Incident

 Vela IncidentThe Vela Incidentsometimes referred to as the South Atlantic Flashwas anunidentified “double flash” of light detected by an American Vela Hotel satellite on September22, 1979, near the Prince Edward Islands off Antarctica which many believe was of nuclearorigin. The most widespread theory among those who believe the flash was of nuclear origin isthat it resulted from a joint South African and Israeli nuclear test.[1][2][3] The topic remainshighly disputed today.

While a “double flash” signal is characteristic of a nuclear weapons test, the signal could alsohave been a spurious electronic signal generated by an aging detector in an old satellite, or ameteoroid hitting the Vela satellite. No corroboration of an explosion, such as the presence ofnuclear byproducts in the air, was ever publicly acknowledged, even though there werenumerous passes in the area by U.S. Air Force planes specifically designed to detect airborneradioactive dust. Other examiners of the data, including the Defense Intelligence Agency(DIA), the U.S. Naval Research Laboratory (NRL), and defense contractors, have come to theconclusion that the flash was a result of a nuclear detonation.[4][5][6] Much information aboutthe event remains classified.


Vela-5A/B Satellites in a cleanroom. The two satellites areseparated after launch.

The “double flash” was detected on September 22, 1979, at 00:53 GMT, by the American Vela satellite6911, which carried various sensors designed specifically to detect nuclear explosions that contravenedthe Partial Nuclear Test Ban Treaty. In addition to being able to detect gamma rays, X-rays, andneutrons, the satellite also contained two silicon solid-state bhangmeter sensors that could detect thedual light flashes associated with an atmospheric nuclear explosion: the initial brief, intense flash,followed by a second, longer flash.[6]

The satellite reported the characteristic double flash of a small atmospheric nuclear explosion of two tothree kilotons, in the Indian Ocean between The Crozet Islands (a very small, sparsely inhabitedFrench possession) and the Prince Edward Islands which belong to South Africa at 47°S 40°E / 47°S40°E. The previous 41 double flashes the Vela satellites detected were all subsequently confirmed to benuclear explosions.[7]

There was, and remains, much doubt[8] as to whether the satellite’s observations were accurate. TheVela Hotel 6911 satellite was one of a pair that had been launched on May 23, 1969, over ten yearsbefore the “double-flash” event, and this satellite was already more than two years beyond its so-called“design lifetime”. This satellite was known to have a failed electromagnetic pulse (EMP) sensor, and ithad developed a fault (in July 1972) in its recording memory, but that fault had cleared itself by March1978.

Bhangmeter light patterns detectedby a pair of sensors on Velasatellite 6911 on Sep 22, 1979.

Additionally, early technical speculation also examined the possibility that the Vela had recorded acombination of natural phenomena, such as lightning in conjunction with a meteor strike. Other earlynews media articles of the time discussed the possibility of a large extraterrestrial object strike, such asan asteroid, occurring.[9] The Vela satellite’s flash detectors were sensitive to lightning superbolts,[10]which resulted in two scientists, John Warren and Robert Freyman from the Los Alamos National Laboratory (then called the Los Alamos Scientific Laboratory), immediately flying to and investigating arare, overland superbolt occurrence on Bell Island, Newfoundland, in April 1978.[11] Theirobservations of the event, called the ‘Bell Island Boom’, noted building structural damage, dead farmanimals and destroyed electrical devices amongst other evidence (the superbolt’s blast was heard 55kilometers away in Cape Broyle, Newfoundland).[12][a] The Bell Island Boom was among some 600“mystery booms” that occurred along the North American eastern seaboard from late 1977 to mid‑1978.[12]

Nonetheless, the initial assessment by the United States National Security Council (NSC), with technical support by the Naval ResearchLaboratory[13] in October 1979 was that the American intelligence community had “high confidence” that the event was a low-yield nuclearexplosion, although no radioactive debris had ever been detected, and there was “no corroborating seismic or hydro-acoustic data.”[14] A laterNSC report revised this position to “a position of agnosticism” about whether a test had occurred or not.[15] The NSC concluded thatresponsibility for a nuclear explosion, if any, should be ascribed to the Republic of South Africa.[14][15]

Several U.S. Air Force WC-135B surveillance aircraft flew 25 sorties over that area of the Indian Ocean soon after the “double flash” wasreported, but they failed to detect any sign of nuclear radiation.[16] Studies of wind patterns confirmed that fall-out from an explosion in thesouthern Indian Ocean could have been carried from there to southwestern Australia.[17] It was reported that low levels of iodine-131 (a short-half-life product of nuclear fission) were detected in sheep in the southeastern Australian States of Victoria and Tasmania soon after theevent. Sheep in New Zealand showed no such trace.[17][18]

The Arecibo ionospheric observatory and radio telescope in Puerto Rico detected an anomalous ionospheric wave during the morning ofSeptember 22, 1979, which moved from the southeast to the northwest, an event which had not been observed previously by the scientists.[19]

Office of Science and Technology evaluation

The administration of USA President Carter asked the Office of Science and Technology Policy (OSTP) to convene a panel ofinstrumentation experts to re-examine the Vela Hotel 6911 data, and to attempt to determine whether the optical flash detected came from anuclear test. The outcome was important to Carter, as his presidency and 1980 re-election campaign prominently featured the themes ofnuclear nonproliferation and disarmament.[20] In particular, the SALT II treaty had been signed three months earlier, and was pendingratification by the United States Senate.[20]

An independent panel of scientific and engineering experts was commissioned by Frank Press, who was the Science Advisor to presidentCarter and the chairman of the OSTP, to evaluate the evidence and determine the likelihood that the event was a nuclear detonation. Thechairman of this science panel itself was Dr. Jack Ruina of the Massachusetts Institute of Technology, and also the former director of theU.S. Department of Defense’s Advanced Research Projects Agency. Reporting in the summer of 1980, the panel noted that there were somekey differences in the detected optical signature from that of an actual nuclear explosion, particularly in the ratio of intensities measured by thetwo detectors on the satellite. The now-declassified report[5] contains details of the measurements made by the Vela Hotel satellite.

The explosion was picked up by a pair of sensors on only one of the several Vela satellites; other similar satellites were looking at differentparts of the earth, or weather conditions precluded them seeing the same event.[21] The Vela satellites had previously detected 41atmospheric tests — by countries such as France and the PRCeach of which was subsequently confirmed by other means, includingtesting for radioactive fallout. The absence of any such corroboration of a nuclear origin for the Vela Incident also suggested that the “doubleflash” signal was a spurious ‘zoo’ signal of unknown origin, possibly caused by the impact of a micrometeoroid. Such ‘zoo’ signals whichmimicked nuclear explosions had been received several times earlier.[22]

Their report noted that the flash data contained “many of the features of signals from previously observed nuclear explosions”,[23] but that“careful examination reveals a significant deviation in the light signature of the September 22 event that throws doubt on the interpretation as anuclear event”. The best analysis that they could offer of the data suggested that, if the sensors were properly calibrated, any source of the“light flashes” were spurious “zoo events”. Thus their final determination was that while they could not rule out that this signal was of nuclearorigin, “based on our experience in related scientific assessments, it is our collective judgment that the September 22 signal was probably notfrom a nuclear explosion”.[24]

Victor Gilinsky (former member of the Nuclear Regulatory Commission) attempted to cast doubt on the science panel’s findings, arguing thatits members were politically motivated.[19] There was some data that seemed to confirm that a nuclear explosion was the source for the“double flash” signal. There was the “anomalous” traveling ionospheric disturbance that was measured at the Arecibo Observatory in Puerto Rico at the same time,[19] but many thousands of miles away in a different hemisphere of the earth. A test in Western Australia conducted afew months later found some increased nuclear radiation levels.[25] However, a detailed study done by New Zealand‘s National RadiationLaboratory found no such evidence of excess radioactivity, and neither did a U.S. Government-funded nuclear laboratory.[26] Los Alamos National Laboratory scientists who worked on the Vela Hotel program have professed their conviction that the Vela Hotel satellite’s detectorsworked properly.[19][27]

Leonard Weiss, at the time Staff Director of the Senate Subcommittee on Energy and Nuclear Proliferation, has also raised concerns about thefindings of the Ad-Hoc Panel, arguing that it was set up by the Carter administration to counter embarrassing and growing opinion that it wasan Israeli nuclear test.[28] Specific intelligence about the Israeli nuclear program was not shared with the panel whose report thereforeproduced the plausible deniability that the administration sought.[28]

Possible responsible parties

If a nuclear explosion did occur, it occurred within the 3000-mile-wide (4,800 km diameter) circle covering parts of the Indian Ocean, the South Atlantic, the southern tip of Africa, and a small part of Antarctica.[29]


In 1979, the DIA reported that the test may have been a Soviet test done in violation of the 1963 Partial Nuclear Test Ban Treaty.[30] TheUSSR had conducted a few secret underwater tests in the Pacific in 1959.[31]


Well before the Vela Incident, American intelligence agencies had made the assessment that Israel probably possessed its own nuclear weapons.[32] According to journalist Seymour Hersh, the detection was the third joint Israeli-South African nuclear test in the Indian Ocean,and the Israelis had sent two IDF ships and “a contingent of Israeli military men and nuclear experts” for the test.[1] Author Richard Rhodesalso concludes the incident was an Israeli nuclear test, conducted in cooperation with South Africa, and that the United States administrationdeliberately obscured this fact in order to avoid complicating relations with South Africa.[2] Likewise, Leonard Weiss offers a number ofarguments to support the test being Israeli, and claims that successive US administrations continue to cover up the test to divert unwantedattention that may portray its foreign policy in a bad light.[3] In the 2008 book The Nuclear Express: A Political History of the Bomb and itsProliferation Thomas C. Reed and Danny B. Stillman stated their opinion that the “double flash” was the result of a joint South African-Israelinuclear bomb test.[33] David Albright stated in his article about the “double flash” event in the Bulletin of Atomic Scientists that “If the 1979flash was caused by a test, most experts agree it was probably an Israeli test”.[34]

South Africa

The Republic of South Africa did have a nuclear weapons program at the time, and it falls within that geographic location. Nevertheless, ithad acceded to the Partial Test Ban Treaty in 1963,[35] and since the fall of apartheid, South Africa has disclosed most of the information onits nuclear weapons program, and according to international inspections and the ensuing International Atomic Energy Agency report, SouthAfrica could not have constructed such a nuclear bomb until November 1979, two months after the “double flash” incident. Furthermore, theIAEA reported that all possible South African nuclear bombs had been accounted for. A Central Intelligence Agency (CIA) report datedJanuary 21, 1980, that was produced for the United States Arms Control and Disarmament Agency concluded that:[36]

In sum, State/INR finds the arguments that South Africa conducted a nuclear test on 22 September inconclusive, even though, ifa nuclear explosion occurred on that date, South Africa is the most likely candidate for responsibility.

The United Nations Security Council Resolution 418 of November 4, 1977 introduced a mandatory arms embargo against South Africa, whichalso required all states to refrain from “any co-operation with South Africa in the manufacture and development of nuclear weapons”.[37]


India had carried out a nuclear test in 1974 (codenamed Smiling Buddha). The possibility that India would test a weapon was considered,since it would be possible for the Indian Navy to operate in those waters so far south, however, this was dismissed as impractical andunnecessary (given the fact that India had signed and ratified the Limited Test Ban Treaty or LTBT in 1963, and had complied with it even inits first test).[38]


Since the “double flash”, if one existed, could have occurred not very far to the west of the French-owned Kerguelen Islands, it is possiblethat the French were testing a small neutron bomb[29] or other small tactical nuclear bomb.

Subsequent developments

Since 1980, some small amounts of new information have emerged. However, most questions remain unanswered:

  • A Los Alamos Scientific Laboratory report from 1981 notes:[39]
    TIROS-N plasma data and related geophysical data measured on 22 September 1979 were analyzed to determine whetherthe electron precipitation event detected by TIROS-N at 00:54:49 universal time could have been related to a surface nuclearburst (SNB). The occurrence of such a burst was inferred from light signals detected by two Vela bhangmeters −2 min beforethe TIROS-N event. We found the precipitation to be unusually large but not unique. It probably resulted from passage ofTIROS-N through the precipitating electrons above a pre-existing auroral arc that may have brightened to an unusually highintensity from natural causes −3 min before the Vela signals….We conclude that such an event, although rare, is not uniqueand, furthermore, that this particular event was associated with an auroral arc that probably existed before the Vela event.Although it may be argued that the segment of the arc sampled by the TIROS-N was intensified by a SNB, we find noevidence to support this thesis or to suggest that the observation was anything but the result of natural magnetosphericprocesses.
  • In October 1984, a National Intelligence Estimate on the South African nuclear program noted:
    There is still considerable disagreement within the Intelligence Community as to whether the flash in the South Atlanticdetected by a US […] satellite in September 1979 was a nuclear test, and if so, by South Africa. If the latter, the need forSouth Africa to test a device during the time frame of this Estimate is significantly diminished.[40]

    A shorter form of this wording was used in a subsequent National Intelligence Council memorandum of September, 1985.[41]

  • In February 1994, Commodore Dieter Gerhardt, a convicted Soviet spy and the commander of South Africa’s Simon’s Town naval baseat the time, talked about the incident upon his release from prison. He said:
    Although I was not directly involved in planning or carrying out the operation, I learned unofficially that the flash was producedby an Israeli-South African test, code-named Operation Phoenix. The explosion was clean and was not supposed to bedetected. But they were not as smart as they thought, and the weather changed — so the Americans were able to pick it up.[42]

    Gerhardt further stated that no South African naval vessels had been involved, and that he had no first-hand knowledge of a nuclear test.Several years after the end of white rule the South African government admitted the apartheid government had indeed possessed sixassembled nuclear weapons but the apartheid government had dismantled them before the changeover to the African National Congressgovernment, there was no mention specifically of the Vela incident or of Israeli cooperation in South Africa’s nuclear program.

  • On April 20, 1997, the Israeli daily newspaper Haaretz quoted the South African deputy foreign minister, Aziz Pahad, as supposedlyconfirming that the “double flash” from over the Indian Ocean was indeed from a South African nuclear test. Haaretz also cited past reportsthat Israel had purchased 550 tons of uranium from South Africa for its own nuclear plant in Dimona. In exchange, Israel allegedly suppliedSouth Africa with nuclear weapons design information and nuclear materials to increase the power of nuclear warheads.[43] Pahad’sstatement was confirmed by the United States embassy in Pretoria, South Africa,[27][44] but Pahad’s press secretary stated that Pahadhad said only that “there was a strong rumor that a test had taken place, and that it should be investigated”. In other words, he was merelyrepeating rumors that had been circulating for years.[45] David Albright, commenting on the stir created by this press report, stated:[45]
    The U.S. government should declassify additional information about the event. A thorough public airing of the existinginformation could resolve the controversy.
  • In October 1999, a white paper that was published by the U.S. Senate Republican Policy Committee in opposition to the ComprehensiveTest Ban Treaty stated:
    There remains uncertainty about whether the South Atlantic flash in September 1979 recorded by optical sensors on the U.S.Vela satellite was a nuclear detonation and, if so, to whom it belonged.[46]
  • In his 2006 book On the Brink, the retired C.I.A. clandestine service officer Tyler Drumheller wrote of his 1983–88 tour-of-duty in SouthAfrica:
    We had operational successes, most importantly regarding Pretoria’s nuclear capability. My sources collectively providedincontrovertible evidence that the apartheid government had in fact tested a nuclear bomb in the South Atlantic in 1979, andthat they had developed a delivery system with assistance from the Israelis.
  • Some American information related to this incident has been declassified in the form of heavily redacted reports and memoranda followingapplications made under the USA Freedom of Information Act; on May 5, 2006, many of these declassified documents were madeavailable through the USA National Security Archive.[6]

Cultural references

  • The Vela Incident formed the basis for a novel by Abe Ariel titled The Last War. The novel describes the test of an Israeli neutron bomb onan uncharted island.[47]
  • The West Wing episodeThe Warfare of Genghis Khanhas a plotline that is very similar to the Vela Incident.[48]
  • The Vela Incident was cited on an episode of NCIS: Los Angeles aired on May 14, 2013.

See also


  1. ^ N.B. quote (emphasis added): “They also picked up large lightning flashes, and it was in part from the Vela satellites that we learnedabout lightning superbolts. About five of every ten million bolts of lightning is classified as a superbolt, which is just what it sounds like:An unusually large bolt of lightning, lasting an unusually long time: About a thousandth of a second. Superbolts are almost always in theupper atmosphere, and usually over the oceans.”


  1. ^ a b Hersh 1991, p. 271.
  2. ^ a b Rhodes 2011, pp. 164-169.
  3. ^ a b Weiss 2011.
  4. ^ Albright 1994, p. 42.
  5. ^ a b Ruina 1980.
  6. ^ a b c Richelson 2006.
  7. ^ Lewiston Morning Tribune 1979, p. 25.
  8. ^ Richelson 2007.
  9. ^ The Ledger 1979.
  10. ^ Turman 1977.
  11. ^ Toledo Blade 1978, p. 1.
  12. ^ a b Dunning 2010.
  13. ^ Amato 2001.
  14. ^ a b National Security Council 1979.
  15. ^ a b Dodson 1980.
  16. ^ USAF 1982.
  17. ^ a b Barnaby 1989, p. 17.
  18. ^ Polakow-Suransky 2010, p. 139.
  19. ^ a b c d Gilinsky 2004.
  20. ^ a b Weiss 2011, p. 3.
  21. ^ Ruina 1980, p. 9.
  22. ^ Ruina 1980, p. 14–16, 18–19.
  23. ^ Ruina 1980, p. 9–11.
  24. ^ Ruina 1980, p. 19.
  25. ^ Barnaby 1989.
  26. ^ Richelson 2007, p. 289.
  27. ^ a b Los Alamos National Laboratory—1997.
  28. ^ a b Weiss 2011, p. 4.
  29. ^ a b Richelson 2007, p. 296.
  30. ^ Richelson 2007, p. 419.
  31. ^ “One hell of a gamble by Aleksandr Fursenko and TimothyNaftali” p132.
  32. ^ CIA 1974.
  33. ^ Broad 2008, p. 2.
  34. ^ Albright 1992, p. 42.
  35. ^ “Treaty Banning Nuclear Weapon Tests in the Atmosphere, in Outer Space and Under Water”. UnitedStates Department of State.
  36. ^ Clarke 1979, p. 11.
  37. ^ United Nations 1977.
  38. ^ Richelson 2007, § 7: The Double Flash.
  39. ^ Hones, Baker & Feldman 1981.
  40. ^ CIA 1984.
  41. ^ National Intelligence Council 1985.
  42. ^ Albright 1994.
  43. ^ McGreal, Chris (March 10, 2006). “Brothers in arms – Israel’s secret pact with Pretoria”. The Guardian (London).
  44. ^ Pike.
  45. ^ a b Albright 1997.
  46. ^ Bartoli 1999.
  47. ^ Ariel, Abe. The last war, Collins Australia, 1988, ISBN 0-7322-2416-0, ISBN 978-0-7322-2416-5.
  48. ^ “The Warfare of Genghis Khan”. The West Wing EpisodeGuide. Retrieved May 26, 2007.


Further reading

  • Marshall, Eliot (November 30, 1979). “Flash Not Missed by Vela Still Veiled in Mist”. Science: 1051–1052.
  • Marshall, Eliot (February 1, 1980). “Scientists Fail to Solve Vela Mystery”. Science: 504–506.
  • Marshall, Eliot (August 29, 1980). “Navy Lab Concludes the Vela Saw a Bomb”. Science: 996–997.
  • Press, Frank (January 16, 1981). “Science and Technology in the White House, 1977 to 1980: Part 2″. Science: 249–256.
  • Torrey, Lee. “Is South Africa a nuclear power?” New Scientist, July 24, 1980, page 268. Retrieved June 16, 2012.

External links

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