Letter to the UN - March 12
- by Earl Budin, M/D., Former Assoc. Clinical Prof. of Radiology, UCLA Medical Center

Earl Budin, M.D.
2415 Stanwood Drive
Santa Barbara, CA 93103-1634


N. Jasentuliyana,
Office for Outer Space Affairs,

12 March 1999

Dear Sir:

In your 16 October 1998 reply to Jonathan M. Haber's letter* you note that information provided to you by the U.S.A. on 4 June 1997 "assured a sufficient degree of nuclear safety of the Cassini space craft." However one month later new information came to public knowledge in the form of the Safety Evaluation Report (SER) July 1997 submitted to NASA by an Independent Nuclear Safety Review Panel (INSRP) composed of representatives of 5 U.S. federal agencies (including NASA!). This report noted multiple serious errors in the various Environmental Impact Statements (EIS) published by NASA about Cassini, which indicate that the document submitted to the U.N. would "fail to assure...safety" of Cassini. Some of the reasons for this are:

  1. NASA predicted that during the Earth fly-by planned August 1999 an accidental re-entry of the space craft into Earth's atmosphere might cause as many as 3,480 fatal cancers (Final EIS, page 4-63); NASA later changed the figure to 120 cancers (Final Supplemental EIS) with no explanation for the new figure. In stark contrast the INSRP estimated the possibility of tens of thousands fatal cancers (SER p. ES4) due to the possible release of 9 kgs. of Plutonium in respirable form (SER p. 3-19).
  2. At no time in any of the multiple EIS did NASA acknowledge the fact that a single Plutonium atom is capable of causing cancer (even though NASA funded the most recent experiments demonstrating this - published in the Proceedings of the National Academy of Sciences, U.S., April 1997) and that a partial release of Plutonium from its containers would involve trillions of Plutonium atoms and the number of fatal cancers could be many times greater than the tens of thousands predicted in the SER.
  3. NASA claimed that the Plutonium containers in Cassini were "designed to withstand re-entry" into our atmosphere (FEIS p. 2-17 and Suppl.FEIS p. E-94). But the INSRP noted that the container were NOT designed to withstand the heat of an accidental re-entry at the planned fly-by speed of 10 miles per second (SER p. 3-24).
  4. 4. As a result of #3, the INSRP on 23 September 1997 requested the U.S. president to delay the launch of Cassini for 2 months since the Earth fly-by would then be at considerably less speed and the health risk would be less by a factor of 30-100 times! This was not done.
  5. NASA based its estimate of the number of cancer deaths on the small average dose received by the world's population in REM of ordinary ionizing radiation (FEIS p. 4-83) - but the SER notes the "probability of a single atom of Plutonium causing cancer" (p. 3-12) since Plutonium emits alpha radiation. The INSRP then strangely concluded its report in direct contradiction to this, reverting back for some inexplicable reason to the effect of an average dose to an individual from ordinary radiation (SER p. 3-12).
  6. The Plutonium on Cassini is placed next to liquid oxygen and hydrogen containers, a potential serous hazard, according to former NASA scientist H. Pohler.
  7. When the current administrator of NASA first assumed his post, NASA's chief scientist stated that Mr. Goldin would have preferred to cancel the Cassini project because of "enormous risk factors" (Space News, March 1994, p. 3).
  8. NASA claims that a serious accident with Cassini such an inadvertent re-entry into Earth's atmosphere is virtually impossible (less than one in a million chance). But a report by the Jet Propulsion Laboratory (May 1997) lists some 18 different types of malfunctions which may occur such as electrical short circuits, meteors striking the craft, and erroneous ground commands. These are beyond the realm of human prediction. NASA recognizes the possibility that the craft might become "uncommandable" (FEIS p. x). Just in the past 12 months there have been multiple space ship malfunctions, some of which resulted in total loss of the craft, including an error in control of the Cassini craft on 11 January 1999 with loss of its orientation which took 4 days to correct. At the Earth fly-by speed panned of 10 miles per second, it would take only a minute for the craft to re-enter our atmosphere and be incinerated.
  9. On 12 August 1998 a Titan IV rocket exploded during launch. This was not the first malfunction of a Titan IV, the same rocket propelling Cassini.
  10. NASA recently announced it was contracting outside organizations to help monitor its space operations, expanding the possibility of a loss of control (Aviation Week & Space Technology, 5 October 1998),

In conclusion, the Cassini Project does not meet the legal Principles adopted by the U.N. on 23 February 1993 relevant to the safe use f nuclear power sources in outer space:

  1. The U.S. withheld information it had (the SER) on the safety assessment of the nuclear power system.
  2. The U.S. failed to acknowledge the special carcinogenicity of Plutonium.
  3. The Plutonium containment system does not prevent nor minimize exposure of the public to radiation.
  4. The requested increase in distance of the fly-by from Earth does not significantly increase safety at the planned speed of 19 km./second.

The Cassini Mission cannot be considered to supply a "sufficient degree of nuclear safety" when it neither prevents nor minimizes the exposure of the public to radiation. An immediate review of the project by an independent scientific organization not affiliated with the U.S.A. is urgently needed, preferably with the possibility of redirecting the probe prior to eh 24 June 1999 planned approach of the space craft's return to Earth.

Earl Budin, M.D.
Associate Clinical Professor of Radiology,
UCLA Medical Center
Los Angeles, CA

* A similar letter, referred to by Dr. Budin, was sent by N. Jasentuliyana to Ms. Selma Brackman, who is the Director of the War and Peace Foundation. NASA posted this letter at http://www.jpl.nasa.gov/cassini/rtg/un/unletter.htm

Posted May 17, 1999