Vela Incident

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Orthographic projection centered on the Prince Edward Islands, the location of the Vela incident
Orthographic projection centered on the Prince Edward Islands, the location of the Vela incident

The Vela Incident (sometimes known as the South Atlantic Flash) was an as-yet unidentified flash of light detected by a United States Vela satellite on September 22, 1979. It has been speculated that the flash was the result of a nuclear weapons test; however, recently declassified information about the event concludes that it was "probably not from a nuclear explosion."[1]

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[edit] Detection

The flash was detected on 22 September 1979, at 00:53 GMT, by a US Vela satellite which was specifically developed to detect nuclear explosions. The satellite reported the characteristic double flash (a very fast and very bright flash, then a longer and less-bright one) of an atmospheric nuclear explosion of two to three kilotons, in the Indian Ocean between Bouvet Island (Norwegian dependency) and the Prince Edward Islands (South African dependencies) at 47° S 40° E. It should be noted that the explosion of some meteors as they are entering the atmosphere can produce energy measured from kilotons (Eastern Mediterranean Event) to megatons (Tunguska event). However, the mechanism is different, and meteors do not produce the double flash characteristic of a nuclear detonation.

Vela-5A/B Satellites in Clean Room. The two satellites are separated after launch.
Vela-5A/B Satellites in Clean Room. The two satellites are separated after launch.

There is much doubt[2] as to whether the satellite's observations were accurate. Vela 6911 was one of a pair launched on 23 May 1969, more than ten years prior to the event, and the satellite was already two years past its design lifespan. It was known to have a failed electromagnetic pulse (EMP) sensor, and in addition had developed a fault (in July 1972) in its recording memory, but the fault had cleared itself by March 1978.

Initial assessment by the U.S. National Security Council in October 1979[3] was that the intelligence community had "high confidence" that the event was a low-yield nuclear explosion, although no radioactive debris was detected, and there was "no corroborating seismic or hydroacoustic data."[3]. A later NSC report revised this to "a position of agnosticism" about whether a test had occurred.[4] They concluded that responsibility should be ascribed to South Africa.[3][4]. Later, the Carter administration asked the Office of Science and Technology Policy (OSTP) to convene a panel of instrumentation experts to examine the Vela 6911 data and determine whether the optical flash detected was from a nuclear test.

[edit] Office of Science and Technology Evaluation

An independent panel of experts was commissioned by Frank Press, who was the Science Advisor to the President and chair of the OSTP, to evaluate the evidence and determine the likelihood that the event was a nuclear detonation. This panel was chaired by Professor Jack Ruina of MIT, the former director of the Department of Defense Advanced Research Projects Agency. Reporting in the summer of 1980, the panel noted that there were some key differences in the detected optical signature from an actual nuclear explosion, particularly in the ratio of intensities measured by the two detectors on the satellite, and that although the brightness of the flash was only explainable if the flash had occurred in cloud-free region, the lack of any nuclear debris found by 25 aircraft overflights could only be explained by a detonation in a heavily overcast site. "Based on our experience in related scientific assessments," it was their collective judgement that the signal was spurious. The panel's conclusion was that the signal "was probably not from a nuclear explosion, although we cannot rule out that this signal was of nuclear origin." The now-declassified report[1] contains details of the measurements made by the Vela satellite. They were not able to conclude definitively what the event actually was. The best analysis they could do of the data suggested that if the sensors were properly calibrated, the event was about 30 meters away from the satellite (and hence was a small event close up, not a big event far away). This was consistent with the hypothesis that a micrometeoroid had impacted the satellite, ejecting a small cloud of debris into space, which reflected sunlight into the sensors.

The fact that the explosion was picked up by only one of the Vela satellites (out of two) seems to support the panel's assertion. Twenty-five United States Air Force flights in the area soon after also failed to detect any sign of radiation.

Some, however, cast doubt on the panel's findings, arguing that they were politically motivated. Evidence proposed to corroborate the nuclear hypothesis has been gathered. The Vela satellites had previously detected 41 atmospheric tests, each of which was subsequently confirmed by other means.

There were some other data which seemed to confirm the explosion. Hydrophones operated by the U.S. Navy detected a signal which was consistent with a small nuclear explosion on or slightly under the surface of the water near the Prince Edward Islands. The radio telescope at Arecibo, Puerto Rico, also detected an anomalous traveling ionospheric disturbance at the same time. A test in Western Australia conducted a few months later found increased radiation levels.[5] However a detailed study done by the New Zealand National Radiation Laboratory found no such evidence as did a U.S. government laboratory.[6] The Los Alamos scientists who worked on the Vela program remain convinced that their satellite worked properly.

[edit] Responsibility

If a nuclear explosion did occur, it occurred within the three-thousand-mile-wide circle covering the Indian Ocean, South Atlantic, southern tip of Africa, and a small part of Antarctica.[7]

South Africa did have a nuclear weapons program at the time, and it falls within that geographic location. Nevertheless, since the fall of apartheid, South Africa has disclosed most of the information on its nuclear weapons program, and according to the subsequent International Atomic Energy Agency report, South Africa could not have constructed such a device until November 1979, two months after the incident. However, American intelligence had detected an unprecedented security lock-down at South African naval facilities the week before the event, which led to suspicions that the putative test was staged from one or more of them.[8]

Israel almost certainly had nuclear weapons in 1979, but it is questioned whether they had the capability to mount a covert test thousands of kilometres away. If it had been an Israeli test, it was almost certainly done with South African cooperation.

U.S. analysts also considered the possibility that it could have been a covert test by a known nuclear state. They concluded that there would be little motivation for the USSR or China in particular to test a nuclear weapon in such a way, unless they were attempting to make it look like South Africa or Israel were covertly testing weapons. As the flash could have occurred in the vicinity of the Kerguelen Islands, it is possible that France was testing a neutron bomb.[7]

India had carried out a nuclear test in 1974 (see Smiling Buddha). The possibility that India would test a weapon was considered, since it would be normal for Indian Navy ships to be in those waters, but dismissed as impracticable and unnecessary.[9] India was not considered as a potential partner of South Africa's nuclear program as it was one of the most vocal critics of apartheid and had no diplomatic or military relationship with South Africa.

It is unlikely any other declared nuclear powers would have conducted such a test. They had little reason to conduct an atmospheric test, and the small size of the blast might reflect a less advanced weapon – though there are many "advanced" reasons for small tests as well, including tactical nuclear weapons (such as neutron bombs) and testing the primary devices for thermonuclear weapons.

Sometimes also mentioned as another potential partner for South Africa in such a test is Taiwan.

United Nations Security Council Resolution 418 of November 4, 1977 introduced a mandatory arms embargo against South Africa, also requiring all States to refrain from "any co-operation with South Africa in the manufacture and development of nuclear weapons".[10] This prohibition could explain why other countries are so reluctant to admit involvement with South Africa's nuclear weapons program.

[edit] Subsequent developments

Since 1980 some new evidence has emerged. However, most questions remain unanswered:

"There is still considerable disagreement within the Intelligence Community as to whether the flash in the South Atlantic detected by a US [...] satellite in September 1979 was a nuclear test, and if so, by South Africa. If the latter, the need for South Africa to test a device during the time frame of this Estimate is significantly diminished."[11] A shorter form of this wording was used in a subsequent National Intelligence Council memorandum of September, 1985.[12]

"Although I was not directly involved in planning or carrying out the operation, I learned unofficially that the flash was produced by an Israeli-South African test, code-named Operation Phenix. The explosion was clean and was not supposed to be detected. But they were not as smart as they thought, and the weather changed – so the Americans were able to pick it up."[13]
  • On April 20, 1997, the Israeli daily newspaper Haaretz, quoted South African Deputy Foreign Minister Aziz Pahad as confirming that the flash over the Indian Ocean was indeed from a South African nuclear test. Soon afterwards Pahad reported that he had been misquoted and that he was merely repeating the rumours that had been circulating for years.
  • Aviation Week & Space Technology/July 21, 1997 page 33 "Admission of 1979 Nuclear Test Finally Validates Vela Data" by William B. Scott/Colorodo Springs

"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."[14]

  • In his 2006 book On the Brink, retired CIA clandestine service officer Tyler Drumheller wrote of his 1983-1988 tour in South Africa:

"We had operational successes, most importantly regarding Pretoria's nuclear capability. My sources collectively provided incontrovertible evidence that the apartheid government had in fact tested a nuclear bomb in the south Atlantic in 1979, and that they had developed a delivery system with assistance from the Israelis."

Some related U.S. information has recently been declassified in the form of heavily redacted reports and memoranda following applications made under Freedom of Information Act. On May 5, 2006, many of these declassified documents were made available through the National Security Archive.

[edit] See also

[edit] Fiction

  • The Vela Incident formed the basis for a novel by Abe Ariel entitled "The Last War". The novel describes the test of an Israeli neutron bomb on an uncharted island.
  • The Vela Incident was probably the inspiration for a Season 5 episode of The West Wing, "The Warfare of Genghis Khan".
  • The Vela Incident is the basis of a 2005 novel by Scott Douglas, "Moby and Ahab on a Plutonium Sea".

[edit] References

  1. ^ a b Ad hoc Panel Report on the September 22 Event, Frank Ruina, chair, May 23, 1980. (PDF of report released by FOIA request)
  2. ^ Jeffrey T. Richelson, Spying on the Bomb: American Nuclear Intelligence from Nazi Germany to Iran and North Korea (New York: W. W. Norton, 2006).
  3. ^ a b c NSC memo dated October 22 1979 PDF file
  4. ^ a b NSC memo dated Jan. 7, 1980 PDF
  5. ^ Frank Barnaby. 1989. The Invisible Bomb, I.B. Tauris & Co. Ltd., ISBN 1-85043-078-0
  6. ^ Richelson, page 289
  7. ^ a b Richelson Op. Cit, page 296.
  8. ^ Unprecedented security lock-down
  9. ^ Richelson Op. Cit, chapter seven, "The Double Flash".
  10. ^ UNSCR 418 of 4 November 1977: States should refrain from "any co-operation with South Africa in the manufacture and development of nuclear weapons"
  11. ^ Trends in South Africa's Nuclear Security Policies and Programs
  12. ^ The Dynamics of Nuclear Proliferation: Balance of Incentives and Constraints
  13. ^ South Africa and the affordable bomb (David Albright)
  14. ^ Comprehensive Test Ban Treaty Cannot Be Verified

[edit] External links