Perseus was the codename of a possible Soviet spy alleged to have breached U.S. national security at Los Alamos during the Manhattan project. This name is also given to a spy at White Sands Missile Range, located further south near Las Cruces, New Mexico. Evidence for his or her existence is based on a few references in KGB archives opened (and later closed) to researchers in the early 1990s, after the fall of the Soviet Union. There are also a few references to Perseus in the Venona project decrypts as PERS. The identity of this person, or even whether or not they actually existed, is unknown, and many of the facts in the matter are questionable.
The first person to publicly write about atomic spy Perseus was Russian intelligence Colonel Vladimir Chikov. Starting in 1991 he wrote a number of articles in Russian periodicals that discussed Perseus. Later in 1996 he published a book with American co-author Gary Kern titled, How Stalin Stole the Atomic Bomb from the Americans (published in France in French).
The Venona project messages contain the unidentified codename "PERS." Not only is pers the linguistic root of the word Perseus but the messages suggest that PERS was a Soviet source on the Manhattan Project. In addition to this, many other individuals, including some associated with the KGB, have affirmed either the specific existence of Perseus or that there remain unidentified atomic spies on the Manhattan Project. According to Chikov, Perseus was at Los Alamos in 1943, a year before Fuchs was assigned there, and in the 1950s Perseus was under the control of Rudolf Abel.
In 1999, arms-control advocate Jeremy Stone alleged that Perseus was "Scientist X", easily identifiable as MIT physicist Philip Morrison. This was a sensational claim because accuser and accused were both highly regarded within the same academic community. Morrison denied that he was a spy and pointed out numerous discrepancies between his biography and that attributed to Perseus. While Stone accepted Morrison's denial and apologized "for the unfavorable publicity", he never fully withdrew the original allegation.
US Cold War historian John Earl Haynes believes that Perseus is "a faked composite by Vladimir Chikov and the SVR combining part of the story of Theodore Hall with misdirection and distortion". citing Gary Kern
- Jeremy Stone, Every Man Should Try: Adventures of a Public Interest Activist (PublicAffairs, 1999)
- David L. Chandler, "Friendship lost in `Perseus' quest", Boston Globe (June 14, 1999)
- "Accuser in Spy Case Accepts a Denial". The New York Times. 1999-05-14. ISSN 0362-4331. Retrieved 2014-03-31.
- Irwin Goodwin, "New Book Unmasks Scientist X as Spy, But Facts of Case Tell a Different Story" Physics Today, July 1999, Vol. 52, Issue 7, p. 39
- Cover Name, Cryptonym, Pseudonym, and Real Name Index johnearlhaynes.org Accessed: 9 September 2010
- The PERSEUS Disinformation Operation at h-hoac Discussion Logs 2006-02-17 Accessed: 2010-09-09.