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|John Whiteside Parsons|
Parsons standing above a JATO canister at JPL, June 1943
|Born||Marvel Whiteside Parsons|
October 2, 1914
Los Angeles, California
|Died||June 17, 1952 (aged 37)|
Cause of death
|Other names||Jack Parsons|
|Alma mater||Pasadena Junior College|
University of Southern California
(received no degrees)
|Occupation||Rocket engineer, chemist, occultist, writer|
|Organization||Jet Propulsion Laboratory|
California Institute of Technology
Aerojet Engineering Corporation
University of Southern California
North American Aviation
Hughes Aircraft Company
|Religion||Thelema (Ordo Templi Orientis until 1946)|
|Violations of the Espionage Act (1951)|
(1946–1952; his death)
|John Whiteside Parsons|
Parsons standing above a JATO canister at JPL, June 1943
|Born||Marvel Whiteside Parsons|
October 2, 1914
Los Angeles, California
|Died||June 17, 1952 (aged 37)|
Cause of death
|Other names||Jack Parsons|
|Alma mater||Pasadena Junior College|
University of Southern California
(received no degrees)
|Occupation||Rocket engineer, chemist, occultist, writer|
|Organization||Jet Propulsion Laboratory|
California Institute of Technology
Aerojet Engineering Corporation
University of Southern California
North American Aviation
Hughes Aircraft Company
|Religion||Thelema (Ordo Templi Orientis until 1946)|
|Violations of the Espionage Act (1951)|
(1946–1952; his death)
John Whiteside Parsons (born Marvel Whiteside Parsons; October 2, 1914 – June 17, 1952), better known as Jack Parsons, was an American rocket engineer, chemist, and Thelemite occultist. Associated with the California Institute of Technology (Caltech), he was the inventor of the castable, composite solid-fuel rocket, and was one of the principal founders of both the Jet Propulsion Laboratory (JPL) and the Aerojet Engineering Corporation.
Born in Los Angeles, California, Parsons was raised by a wealthy family in Pasadena. Inspired by science fiction literature, he developed an early interest in rocketry and in 1928 began amateur rocket experiments with school friend Ed Forman. He was forced to drop out of Pasadena Junior College and Stanford University due to financial difficulties during the Great Depression, but in 1934 he united with Forman and graduate student Frank Malina to form the Caltech-affiliated GALCIT Rocket Research Group, supported by Guggenheim Aeronautical Laboratory chairman Theodore von Kármán. In 1939 they gained funding from the National Academy of Sciences to work on Jet-Assisted Take Off (JATO) for the U.S. military, and upon this expansion renamed themselves the Jet Propulsion Laboratory. In 1942 they founded Aerojet to develop and sell their JATO technology.
After a brief involvement in Marxism, in 1939 Parsons converted to Thelema, the English occultist Aleister Crowley's new religious movement. In 1941 he joined the Agape Lodge, the Californian branch of the Thelemite Ordo Templi Orientis (OTO). At Crowley's bidding, he took over the position of lodge leader from Wilfred Talbot Smith in 1942 and ran it from his manor on Orange Grove Avenue, Pasadena. With his friend L. Ron Hubbard he began the Babalon Working, a series of rituals designed to invoke the Thelemic goddess Babalon to Earth. They continued the procedure with Marjorie Cameron, whom Parsons married in 1946. After Hubbard stole his life savings, Parsons resigned from the OTO and went through various jobs while acting as a consultant for Israel's rocket program. Amid the climate of McCarthyism he was accused of espionage and left unable to work in rocketry. Parsons died in a home laboratory explosion at the age of 37; the police ruled it an accident, but many associates suspected suicide or murder.
Parsons' death attracted national attention, and his occult and individualist political writings were posthumously published. Occultists cite Parsons as one of the most significant figures in propagating Thelema across North America. Scientific historians recognize his contributions to rocket propulsion chemistry and design, and his pioneering advocacy for their use in space exploration and human spaceflight. For the latter reasons, and because of his role in the foundation of JPL, Parsons is regarded as among the most important figures in the history of the U.S. space program. He has been the subject of several biographies and fictionalized portrayals.
Marvel Whiteside Parsons was born on October 2, 1914, at the Good Samaritan Hospital in Los Angeles.  His parents, Ruth Virginia Whiteside (c. 1893–1952) and Marvel H. Parsons (c. 1894–1947), had moved to California from Massachusetts the previous year, purchasing a house on Scarf Street in downtown Los Angeles. Although their son was his father's namesake, he was known in the household as Jack. Their marriage broke down soon after Jack's birth, when Ruth discovered that his father had made numerous visits to a prostitute, and she filed for divorce in March 1915. Parsons' father returned to Massachusetts after being publicly exposed as an adulterer, with Ruth forbidding him from having any contact with Jack. Parsons' father would later join the armed forces, reaching the rank of major, and marry a woman with whom he had a son named Charles—a half-brother whom Jack would only meet once. Although she retained her ex-husband's surname, Ruth ceased to call her son Marvel, instead referring to him as John, whereas many other friends throughout his life knew him as Jack. Ruth's parents Walter and Carrie Whiteside moved to California to be with Jack and their daughter, using their wealth to buy an up-market house on South Orange Grove Avenue in Pasadena—known locally as "Millionaire's Mile"—where they could live together. Jack was surrounded by domestic servants and soon became spoiled. Having few friends, he lived a solitary childhood and spent much time reading; he took a particular interest in works of mythology, Arthurian legend, and the Arabian Nights. Through the works of Jules Verne he became interested in science fiction (then known as scientifiction), and became a keen reader of pulp magazines like Amazing Stories. It was this interest in science fiction that led to his early interest in rocketry.
At age twelve, Parsons began attending Washington Junior High School, where he performed poorly—something biographer George Pendle attributed to undiagnosed dyslexia—and was heavily bullied for his upper class status and perceived effeminacy. Although unpopular, he formed a strong friendship with Edward Forman, a boy from a poor working class family who shared his interest in science fiction and rocketry. In 1928 the pair—adopting the Latin motto per aspera ad astra—began engaging in homemade gunpowder-based rocket experiments in the nearby Arroyo Seco canyon, as well as the Parsons family's back garden, which left it potted with craters from explosive test failures. They used commonly available fireworks such as cherry bombs in their rockets, and Parsons suggested using glue as a binding agent to reduce the rocket fuel's volatility, which was noted by Forman as early example of the former's inventiveness. This research became more complex when they began using materials such as aluminium foil. Parsons had also begun to investigate occultism, and independently performed a ritual intended to invoke the Devil into his bedroom; he worried that the invocation was successful and was so frightened that he ceased such activities until adulthood. In 1929 Parsons began attending John Muir High School, where he maintained an insular friendship with Forman and was a keen participant in the sports of fencing and archery, and he developed a lifelong passion for the former. After receiving poor school results, Parsons' mother sent him away to study at a private boarding school in San Diego—the Brown Military Academy for Boys—but he was expelled for blowing up the toilets.
The Parsons family spent the summer of 1929 on a tour of Europe before returning to Pasadena, where they moved into a house on San Rafael Avenue. With the onset of the Great Depression their fortune began to dwindle, and in July 1931 Jack's grandfather Walter died. After graduating from John Muir High in 1931, Parsons began studying at the privately-run University School, a liberal institution that took an unconventional approach to teaching. He flourished at the school, becoming editor of the school's newspaper El Universitano and winning an award for literary excellence, while teachers that had trained at the nearby California Institute of Technology (Caltech) honed his attentions on the study of chemistry through practical demonstrations. With the family's financial difficulties deepening, Parsons began working during weekends and school holidays at the offices of the Hercules Powder Company, where he learned more about explosives and their potential use in rocket propulsion. He and Forman continued to independently explore the subject in their spare time, building and testing different rockets—sometimes with materials that he had stolen from work. Parsons soon constructed his own solid-fuel rocket engine and underwent a brief correspondence with the German rocket engineer Wernher von Braun; the pair talked for hours over the telephone about rocketry in their respective countries as well as their own research. Pendle attributes the sudden dissipation of their conversations to the men's mutual reticence about disclosing the technical details of their discoveries.
Graduating from University School in the summer of 1933, Parsons moved with his mother and grandmother to a more modest house on St. John Avenue, where he continued to pursue his interests in classical literature and writing poetry. In the autumn he enrolled in Pasadena Junior College with the hope of earning an associate degree in physics and chemistry, but was forced to drop out after only a term because of his financial situation and he took up permanent employment at the Hercules Powder Company. His employers then sent him to work at their manufacturing plant in Pinole on San Francisco Bay, where he earned a relatively high wage of $100 a month; however, he was plagued by headaches caused by exposure to nitroglycerin. He saved money in the hope of continuing his academic studies and began a degree in chemistry at Stanford University, but again found the tuition fees unaffordable and returned to Pasadena.
In the hope of gaining access to the state-of-the-art resources of Caltech to use in their rocketry programs, Parsons and Forman attended a lecture on the work of Austrian rocket engineer Eugen Sänger and hypothetical above-stratospheric aircraft by the institute's William Bollay—a PhD student specializing in rocket-powered aircraft—and approached him to express their interest in designing a liquid fuel rocket motor. Bollay redirected them to another PhD student named Frank Malina, a mathematician and mechanical engineer composing a thesis on rocket propulsion who shared their interests and soon befriended Parsons. Parsons, Forman, and Malina applied for funding from Caltech together; they did not mention that their ultimate objective was to develop rockets for space exploration, realizing that most of the scientific establishment then relegated such ideas to science fiction. While Caltech's Clark Blanchard Millikan immediately rebuffed them, Malina's doctoral advisor Theodore von Kármán saw more promise in their proposal and agreed to allow them to operate under the auspices of the university's Guggenheim Aeronautical Laboratory (GALCIT). Naming themselves "The GALCIT Rocket Research Group", they gained access to the university's specialist equipment, though the economics of the Great Depression left von Kármán unable to finance them.
The trio focused their distinct skills on collaborative rocket development; Parsons was the chemist, Forman the machinist, and Malina the technical theoretician. Malina wrote in 1968 that the self-educated Parsons "lacked the discipline of a formal higher education, [and] had an uninhibited and fruitful imagination." The informally trained Parsons and Forman who, as described by Geoffrey A. Landis, "were eager to try whatever idea happened to spring to mind", contrasted with the approach of Malina, who insisted on the need for scientific discipline as informed by von Kármán. Landis said that their creativity, however, "kept Malina focused toward building actual rocket engines, not just solving equations on paper". Sharing socialist values, they operated on an egalitarian basis; Malina taught the others about scientific procedure and they taught him about the practical elements of rocketry. They often socialized, drinking alcohol and smoking marijuana, while Malina and Parsons set about writing a novel—left unfinished—with strong anti-capitalist and pacifist themes.
Parsons had met Helen Northup at a local church dance and proposed marriage in July 1934. She accepted and they were married in April 1935 at the Little Church of the Flowers in Forest Lane Memorial Park, Glendale, before undertaking a brief honeymoon in San Diego. They moved into a house on South Terrace Drive, Pasadena, while Parsons gained employment for the explosives manufacturer Halifax Powder Company at their facility in Saugus. Much to Helen's dismay, Parsons spent most of his wages funding the GALCIT Rocket Research Group. For extra money he manufactured nitroglycerin in their home and at one point he pawned Helen's engagement ring and would often ask her family for loans.
Malina recounted that "Parsons and Forman were not too pleased with an austere program that did not include at least the launching of model rockets", but The Group reached the consensus of developing a working static rocket-motor before embarking on more complex research. They contacted liquid-fuel rocket pioneer Robert H. Goddard and he invited Malina to his facility, but he was not interested in cooperating—having being subjected to widespread derision for his work in rocketry. They were instead joined by Caltech masters students Apollo M. O. Smith (known as "Amo"), Carlos C. Wood, William C. Rockefeller and Rudolph Schott; Schott was relied upon for the use of his pickup truck to transport equipment. Their first motor took place near the Devil's Gate Dam in the Arroyo Seco in late October 1936. Parsons' biographer John Carter described the layout of the contraption as showing
oxygen flowing from one side, with methyl alcohol (the fuel) and nitrogen flowing from the other side. Water cooled the rocket during the burn. Thrust pulled down a spring which measured force. The deflection of the spring measured the force applied to it. A small diamond tip on the apparatus scratched a glass plate to mark the furthest point of deflection. The rocket and mount were protected by sandbags, with the tanks (and the experimenters) well away from it.
Three attempts to fire the rocket failed; on the fourth the oxygen line was accidentally ignited and perilously billowed fire at The Group, but they viewed this experience as formative. They continued their experiments throughout the final quarter of 1936; after the final test was successfully completed in January 1937 von Kármán agreed that they could perform their future experiments at an exclusive rocket testing facility on campus.
In April 1937 a Caltech mathematician Qian Xuesen (a Chinese citizen) joined The Group. Several months later Weld Arnold, a Caltech laboratory assistant who worked as The Group's official photographer, also joined. The main reason for Arnold's appointment to this position was his provision of a donation to The Group on behalf of an anonymous benefactor whose identity was never revealed. They became well known on campus, earning the moniker of the "Suicide Squad" for the dangerous nature of some of their experiments and attracting attention from the local press. Parsons himself gained further media publicity when he appeared as an expert explosives witness in the trial of Earl Kynette, the head of police intelligence in Los Angeles who was accused of setting a bomb to kill private investigator Harry Raymond. When Kynette was convicted largely on Parsons' testimony, which included his construction of a replica of the device Kynette used in the murder, his identity as an expert scientist in the public eye was established despite his lack of a university education. While working at Caltech, Parsons was admitted to evening courses in chemistry at the University of Southern California (USC), but distracted by his GALCIT workload he attended sporadically and received unexceptional grades.
By early 1938 the Group had made their static rocket motor, which originally burned for three seconds, run for over a minute. In May that year, Parsons was invited by Forrest J Ackerman to lecture on these advances at Chapter Number 4 of the Los Angeles Science Fiction League (LASFL). Although he never joined the society, he occasionally attended their talks; on one occasion conversing with a teenage Ray Bradbury. Another scientist to become involved in the GALCIT project was Sidney Weinbaum, a Jewish refugee from Europe who was a vocal Marxist; he led Parsons, Malina, and Qian in their creation of a largely secretive communist discussion group at Caltech, which became known as Professional Unit 122 of the Pasadena Communist Party. Although Parsons subscribed to the People's Daily World and joined the American Civil Liberties Union, he refused to join the American Communist Party, causing a break in his and Weinbaum's friendship. This ideological divide, coupled with the need to focus on paid employment, led to the disintegration of much of the Rocket Research Group, leaving only its three founding members by late 1938.
In January 1939 John and Frances Baxter, a brother and sister who had befriended Jack and Helen Parsons, took Jack to the Church of Thelema in Winona Boulevard, Hollywood, where he witnessed the performance of The Gnostic Mass. Notable attendees of the church had included Hollywood actor John Carradine and gay rights activist Harry Hay. Parsons was intrigued, having already heard of Thelema's founder Aleister Crowley after reading a copy of Crowley's text Konx om Pax (1907). Prior to becoming aware of Crowley, Parsons' interest in esotericism was developed through his reading of The Golden Bough (1890), a work in comparative mythology by Scottish social anthropologist James George Frazer. Parsons had also attended lectures on Theosophy by philosopher Jiddu Krishnamurti with Helen, but disliked the belief system's sentiment of "the good and the true".
Parsons was introduced to leading members Regina Kahl, Jane Wolfe, and Wilfred Talbot Smith at the mass. Feeling both "repulsion and attraction" for Smith, Parsons continued to sporadically attend the Church's events for a year. He continued to read Crowley's works, which increasingly interested him, and encouraged Helen to read them. Parsons came to believe in the reality of magic—or magick in Thelemic terms—as a force that could be explained through quantum physics. He tried to interest his friends and acquaintances in Thelema, taking science fiction authors Jack Williamson and Cleve Cartmill to a performance of The Gnostic Mass. Although they were unimpressed, Parsons was more successful with Grady Louis McMurtry, a young Caltech student whom he had befriended, as well as McMurtry's fiancée Claire Palmer, and Helen's sister Sara "Betty" Northrup.
Parsons and his wife were initiated into the Agape Lodge of the Ordo Templi Orientis in February 1941. Parsons adopted the Thelemic motto of Thelema Obtenteum Proedero Amoris Nuptiae, a Latin mistranslation of "The establishment of Thelema through the rituals of love". The initials of this motto spelled out T.O.P.A.N., also serving as the declaration "To Pan". Commenting on Parsons' errors of translation, in jest Crowley said that "the motto which you mention is couched in a language beyond my powers of understanding". Parsons also adopted the Thelemic title Frater T.O.P.A.N—with T.O.P.A.N represented in Kabbalistic numerology as 210—the name with which he frequently signed letters to occult associates—while Helen became known as Soror Grimaud. Smith wrote to Crowley claiming that Parsons was "a really excellent man ... He has an excellent mind and much better intellect than myself ... JP is going to be very valuable". Wolfe wrote to Crowley's designated successor as OTO Outer Head, Karl Germer, that Parsons was "an A1 man ... Crowleyesque in attainment as a matter of fact." Crowley concurred with such assessments, informing Smith that Parsons "is the most valued member of the whole Order, with no exception!"
At von Kármán's suggestion, Malina approached the National Academy of Sciences (NAS) Committee on Army Air Corps Research to request funding for research into what they referred to as "jet propulsion", a term chosen to avoid the stigma attached to rocketry. The military were interested in jet propulsion as a means of getting aircraft quickly airborne where there was insufficient room for a full-length runway, and gave the Rocket Research Group $1,000 to put together a proposal on the feasibility of Jet-Assisted Take Off (JATO) by June 1939. Parsons et al became the first U.S. government-sanctioned rocket research group; simultaneously, they began experiments involving model, black powder motor-propelled multistage rockets. In a research paper submitted to the American Institute of Aeronautics and Astronautics, Parsons reported these rockets reaching velocities of 4,875 miles per hour, thereby demonstrating the potential of solid fuels as being significantly more effective than liquid types primarily preferred by researchers such as Goddard. In light of this progress, Caltech and the GALCIT Group received an additional $10,000 rocketry research grant.
Although a quarter of their funding went on repairing damage to Caltech buildings caused by their experiments, in June 1940 they submitted a report to the NAS in which they showed the feasibility of the project for the development of JATO and requested $100,000 to continue; however, they only received $22,000. Now known as GALCIT Project Number 1, they continued to be ostracized by other Caltech scientists who grew increasingly irritated by their accidents and noise pollution, and were made to relocate their experiments back to the Arroyo Seco, at a site with unventilated, corrugated iron sheds that served as both research facilities and administrative offices. It was here that JPL would be founded. Parsons and Forman's rocket experiments were the cover story of the August 1940 edition of Popular Mechanics, in which the pair discussed the prospect of rockets being able to ascend above Earth's atmosphere and orbit around it for research purposes, as well as reaching the Moon.
For the JATO project, they were joined by Caltech mathematician Martin Summerfield and 18 workers supplied by the Works Progress Administration. Former colleagues like Qian were prevented from returning to the project by the Federal Bureau of Investigation (FBI), who ensured the secrecy of the operation and restricted the involvement of foreign nationals and political extremists. The FBI was satisfied that Parsons was not a Marxist but were concerned when Thelemite friend Paul Seckler used Parsons' gun in a drunken car hijacking, for which Seckler was imprisoned in San Quentin State Prison for two years. Englishman George Emerson replaced Arnold as the Group's official photographer and remained in the same occupation at JPL for 40 years.
The solid JATO fuel invented by Parsons consisted of amide, corn starch, and ammonium nitrate bound together in the JATO unit with glue and blotting paper. It was codenamed GALCIT-27, implying the previous invention of 26 new fuels. The first JATO tests using an Ercoupe plane took place in late July 1941; static experiments resulted in explosions that damaged the aircraft. Parsons theorized that this was because the ammonium nitrate became dangerously combustible following overnight storage, during which temperature and consistency changes had resulted in a chemical imbalance. Parsons and Malina accordingly devised a method in which they would fill the JATOs with the fuel in the early mornings shortly before the tests, enduring sleep deprivation to do so. On August 21, 1941, Navy Captain Homer J. Boushey, Jr.—watched by such figures as Clark Millikan and William F. Durand—piloted the JATO-equipped Ercoupe at the March Field Army Air Force Base in Moreno Valley, California. It proved a success and reduced takeoff distance by 30%, but one of the JATOs partially exploded. Over the following weeks 62 further tests took place, and the NAS increased their grant to $125,000. During a series of static experiments, an exploding JATO did significant damage to the fuselage in the Ercoupe's tail; one observer optimistically noted that "at least it wasn't a big hole", but necessary repairs delayed their efforts.
The military ordered a flight test using liquid fuel rather than the pre-existing solid fuel in early 1942. Upon the United States' entry into the Second World War in December 1941, members of the Group realized they could be drafted directly into military service if they failed to provide viable JATO technology for the military. Informed by their left-wing politics, aiding the war effort against the Axis powers was as much of a moral vocation to Parsons, Forman and Malina as it was a practical one. Parsons, Summerfield and the GALCIT workers focused on the task and found success with a combination of gasoline with red fuming nitric acid as its oxidizer—with the latter, suggested by Parsons, proving to be an effective substitute for liquid oxygen. The testing of this fuel resulted in another calamity, however, when the testing rocket motor exploded; the fire, containing shed fragments and shrapnel inexplicably left the experimenters unscathed. Malina solved the problem by replacing the gasoline with aniline, resulting in a successful test launch of a JATO-equipped A-20A plane at the Mura Auxiliary Air Field in the Mojave Desert. Providing a thrust five times more powerful than GALCIT-27, and again reducing takeoff distance by 30%, Malina said, "We now have something that really works and we should be able to help give the Fascists hell!"
Parsons, however, remained motivated to address the malfunctions observed during the Ercoupe tests. In 1942—assisted by Caltech graduate students Mark Muir Mills and Fred S. Miller—he focused his attention on developing an effective method of restricted burning when using solid rocket fuel, as the military demanded JATOs that could provide over 100 pounds of thrust without any risk of exploding. Although solid fuels such as GALCIT-27 were less volatile than their liquid counterparts, they were disfavored for military JATO use as they provided less immediate thrust and did not have the versatility of being turned on and off mid-flight. Parsons tried to resolve GALCIT-27's volatility issue with GACLIT-46, which replaced the former's ammonium nitrate with guanidine nitrate. To avoid the problems seen with ammonium nitrate, he had GALCIT-46 supercooled and then superheated prior to testing. When it failed the test, he realized that the fuel's binding black powders rather than the oxidizers which had resulted in their volatility, and in June that year had the idea of using liquidized asphalt as an appropriate binding agent with potassium perchlorate as its oxidizer. Malina said that Parsons was inspired to use asphalt by the ancient incendiary weapon Greek fire, while in a 1982 talk for the International Association of Astronomical Artists Captain Boushey stated that Parsons experienced an epiphany after watching manual workers using molten asphalt to fix tiles onto a roof. Known as GALCIT-53, this fuel proved to be significantly less volatile than The Group's earlier concoctions, fulfilling Parsons' aim of creating a restricted-burn rocket fuel inside a castable container, and providing a thrust 427% more powerful than that of GALCIT-27. This set a precedent which according to his biographer John Carter "changed the future of rocket technology": the insular asphalt casting allowing for mass-production and indefinite storage of The Group's invention and transforming solid fuel agents into a safe and viable form of rocket propulsion. Plasticized variants of Parsons' solid-fuel design—invented by JPL's Charles Bartley—were later used by NASA in Space Shuttle Solid Rocket Boosters and by the Strategic Air Command in Polaris, Poseidon and Minuteman intercontinental ballistic missiles.
In December 1941 The Group had agreed to produce and sell 60 JATO engines to the United States Army Air Corps. To do so they formed the Aerojet Engineering Corporation in March 1942, into which Parsons, Forman, Malina, von Kármán, and Summerfield each invested $250, opening their offices on East Colorado Street and bringing in Amo Smith as their engineer. Andrew G. Haley was recruited by von Kármán as their lawyer and treasurer. Although Aerojet was a for-profit operation that provided technology for military means, the founders' mentality was rooted in the ideal of using rockets for peaceful space exploration. As Haley recounted von Kármán requesting: "we will make the rockets—you must make the corporation and obtain the money. Later on you will have to see that we all behave well in outer space."
Aerojet's first two contracts were from the U.S. Navy; the Bureau of Aeronautics requested a solid-fuel JATO and the Wilbur Wright Field requested a liquid-fuel unit. The Air Corps had requested two thousand JATOs from Aerojet by late 1943, committing $256,000 toward Parsons' solid fuel type. Despite this drastically increased turnover, the company continued to operate informally and remained intertwined with the GALCIT project. Caltech astronomer Fritz Zwicky was brought in as head of the company's research department, and Haley replaced von Kármán as Aerojet chairman and imposed payroll cuts instead of reducing JATO output; the alternative was to cut staff numbers while maintaining more generous salaries, but Haley's priority was Aerojet's contribution to the war effort.
Parsons' newfound credentials and financial security gave him the opportunity to travel more widely throughout the U.S. as an ambassador for Aerojet, meeting with other rocket enthusiasts. In New York he met with Karl Germer, the head of the OTO in North America and in Washington D.C. he met Joseph Auslander, donating some of Crowley's poetry books to the Library of Congress. He also became a regular at the Mañana Literary Society, which met in Laurel Canyon at the home of Parsons' friend Robert A. Heinlein and included science fiction writers such as Cleve Cartmill, Jack Williamson, and Anthony Boucher. One of Parsons' favorite works of fiction was Williamson's Darker Than You Think, a novelette published in the fantasy magazine Unknown in 1940, which inspired his later occult workings. Boucher had used Parsons as a partial basis for the character of Hugo Chantrelle in Rocket to the Morgue (1942).
Helen went away for a period in June 1941, during which Parsons, encouraged to do so by the sexually permissive attitude of the OTO, began a sexual relationship with her 17-year-old sister, Sara. Upon Helen's return, Sara asserted that she was Parsons' new wife, and Parsons himself admitted that he found Sara more sexually attractive than his wife. Conflicted in her feelings, Helen sought comfort in Talbot Smith and began a relationship with him that would last for the rest of his life; the four remained friends. The two couples, along with a number of other Thelemites, relocated from Winona Boulevard together, moving to a large Craftsman-style house at 1003 South Orange Grove Avenue, Pasadena. They all contributed to the rent of $100 a month and lived communally in what became the new base of the Agape Lodge. Parsons decorated his new room with a copy of the Stele of Revealing, a statue of the god Pan, and his collection of swords and daggers, which he hung on the walls. He converted the garage and laundry room into a chemical laboratory and often held science fiction discussion meetings in the kitchen.
Although there were many arguments among the commune members, Parsons remained dedicated to Thelema. He gave almost all of his salary to the OTO while actively seeking out new members—including Forman—and financially supporting Crowley in London through Germer. He invited many of his colleagues to the lodge parties, to the annoyance of coworkers and management from Aerojet who previously tolerated Parsons' occultism as harmless eccentricity; he was frequently observed reciting Crowley's poem "Hymn to Pan" in an ecstatic manner compared to the preaching of Billy Graham during rocket tests. However, they disapproved of his hesitancy to separate his personal and professional vocations, and soon the Agape Lodge came under investigation by both the Pasadena Police Department and the FBI. Both had received allegations of a "black magic cult" involved in sexual orgies; one complainant was a 16-year-old boy who claimed that he was raped by lodge members. Neither agency found evidence of illegal activity and came to the conclusion that the lodge constituted no threat to national security. Having been a long-term heavy-user of alcohol and marijuana, Parsons now habitually used cocaine, amphetamines, peyote, mescaline and opiates as well. He continued to have sexual relations with multiple women, including McMurtry's fiancee Claire. When Parsons paid for Claire to have an abortion, McMurtry was angered and their friendship broke down.
Crowley and Germer wanted to see Smith removed as head of the Agape Lodge, believing that he had become a bad influence on other lodge members. Parsons and Helen wrote to them to defend their mentor but Germer nevertheless ordered him to stand down and Parsons was appointed as temporary head of the Lodge. Some veteran Lodge members disliked Parsons' influence, concerned that it encouraged excessive sexual polyandry detrimental to the focused practice of Thelema, but his charismatic orations at Lodge meetings assured his popularity among the majority of followers. Parsons soon created the Thelemite journal Oriflamme, in which he published his own poetry, but Crowley was unimpressed and the project was soon shelved. Helen gave birth to Smith's son in April; the child was named Kwen Lanval Parsons. Smith and Helen left with Kwen for a two-room cabin in Rainbow Valley in May. Concurrently in England, Crowley undertook an astrological analysis of Smith's birth chart and came to the conclusion that Smith was the incarnation of a god, greatly altering his estimation of him; Smith however remained skeptical—Crowley's analysis was seemingly deliberately devised in Parsons' favor, encouraging Smith to step down from his role in the Agape Lodge and instructing him to take a meditative retreat. Refusing to take orders from Germer anymore, Smith resigned from the OTO. Parsons—who remained sympathetic and friendly to Smith during the conflict and was weary of Crowley's "appalling egotism, bad taste, bad judgement, and pedanticism"—ceased lodge activities and resigned as its head, but withdrew his resignation after receiving a pacifying letter from Crowley.
By the summer of 1943 Aerojet was operating on a budget of $650,000. The same year Parsons and von Kármán traveled to Norfolk, Virginia to consult on a new JATO contract for the U.S. Navy on the invitation of Secretary of the Navy Frank Knox. Though JATOs were being mass-produced for military applications, JATO-propelled aircraft could not "keep up" with larger, bomber planes taking off from aircraft carrier runways. Parsons demonstrated the efficacy of the newer JATOs to solve this issue by equipping a Grumman plane with solid-fuel units; its assisted takeoff from the USS Charger was successful, but produced smoke containing a noxious, yellow-colored residue. The Navy guaranteed Parsons a contract on the condition that this residue was removed; this led to the invention of Aeroplex, a technology for smokeless vapor trails developed at Aerojet under Parsons' command.
As the U.S. became aware that Nazi Germany had developed the V-2 rocket, the military—following recommendations from von Kármán based upon research using British intelligence—placed a renewed impetus on its own rocket research, reinstating Qian to the GALCIT project. They gave The Group a $3 million grant to develop rocket-based weapons, and The Group was expanded and renamed the Jet Propulsion Laboratory (JPL). By this point the Navy were ordering 20,000 JATOs a month from Aerojet, and in December 1944 Haley negotiated for the company to sell 51% of its stock to the General Tire and Rubber Company to cope with the increased demand. However, Aerojet's Caltech-linked employees—including Zwicky, Malina and Summerfield—would only agree to the sale on the condition that Parsons and Forman were removed from the company, viewing their occult activities as disreputable. The pair were unfazed, informing Haley of their prediction that the rocket industry would become obsolete in the postwar age and seeing more financial incentive in starting a chain of laundromats. Haley persuaded them to sell all of their stock, resulting in Parsons leaving the company with $11,000. With this money he bought the lease to 1003 South Orange Grove Avenue, which had come to be known as "the Parsonage" after him.
Now disassociated from JPL and Aerojet, Parsons and Forman founded the Ad Astra Engineering Company. Ad Astra was subject to an FBI investigation under suspicion of espionage when security agents from the Manhattan Project discovered that Parsons and Forman had procured a chemical used in a top secret project for a material known only as x-metal, but they were later acquitted of any wrongdoing. Parsons continued to financially support Smith and Helen, although he asked for a divorce from her and ignored Crowley's commands by welcoming Smith back to the Parsonage when his retreat was finished. Parson continued to hold OTO activities at the Parsonage but began renting rooms at the house to non-Thelemites, including journalist Nieson Himmel, Manhattan Project physicist Robert Cornog, and science fiction artist Louis Goldstone. Parsons attracted controversy in Pasadena for his preferred clientele. Parsonage resident Alva Rogers recalled in a 1962 article: "In the ads placed in the local paper Jack specified that only bohemians, artists, musicians, atheists, anarchists, or any other exotic types need to apply for rooms—any mundane soul would be unceremoniously rejected".
Science fiction writer and U.S. Navy officer L. Ron Hubbard soon moved in to the Parsonage; he and Parsons became close friends. Parsons informed Crowley that Hubbard was "the most Thelemic person I have ever met". Although Parsons and Sara were in an open relationship encouraged by the OTO's polyandrous sexual ethics, she became enamored with Hubbard and Parsons became intensely jealous. Motivated to find a new partner through occult means, Parsons began to devote increasing amounts of time to the "dark side" of magic. He became interested in the iconography of witchcraft, causing concern among fellow OTO members, who believed that he was invoking troublesome spirits into the Parsonage. Wolfe wrote to Crowley that "our own Jack is enamored with Witchcraft, the houmfort, voodoo. From the start he always wanted to evoke something—no matter what, I am inclined to think, as long as he got a result." Parsons reported paranormal events in the house resulting from his rituals; including poltergeist activity, sightings of orbs and ghostly apparitions, and disembodied voices. Pendle suggested that Parsons was particularly susceptible to these interpretations and attributed the voices to a prank by Hubbard and Sara. One ritual allegedly brought screaming banshees to the windows of the Parsonage, an incident that disturbed Forman for the rest of his life. Parsons was nevertheless dissatisfied with these results and was determined to conjure a new lover. He performed a series of rituals based on Enochian magic during which he masturbated onto magical tablets, accompanied by Sergei Prokofiev's Second Violin Concerto and using his own semen and blood for this purpose. Describing this magical operation as the Babalon Working, he hoped to bring about the incarnation of a Thelemite female messiah Babalon onto Earth. He allowed Hubbard to take part as his "scribe", believing that he was particularly sensitive to detecting magical phenomena.
Their final ritual took place in the Mojave Desert on 18 January 1946, during which Parsons abruptly decided that his undertaking was complete, and on returning to the Parsonage he discovered that a woman named Marjorie Cameron—an unemployed illustrator and former WAVE—had come to visit. Believing her to be the "elemental" woman and manifestation of Babalon that he had invoked, Parsons began performing sex magic rituals with Cameron, who acted as his "Scarlet Woman", while Hubbard continued participate as the amanuensis. Parsons also aimed to magically fertilize a "magickal child" (inspired by Crowley's 1917 novel Moonchild) through immaculate conception, which, when born to a woman somewhere on Earth nine months following the working's completion, would become the messiah of Thelema. Unlike the rest of the household, Cameron knew nothing at first of Parsons' magical intentions: "I didn't know anything about the OTO, I didn't know that they had invoked me, I didn't know anything, but the whole house knew it. Everybody was watching to see what was going on." Despite this ignorance, and her skepticism about Parsons' magic, Cameron reported her sighting of a UFO to him which she believed was a materialization of paranormal energy.
As described by Richard Metzger, the purpose of the Babalon Working was "a daring attempt to shatter the boundaries of space and time" facilitating, according to Parsons, the emergence of Thelema's Aeon of Horus. Although Crowley was bewildered and concerned by the endeavor, criticizing it as reckless and naive, Parsons was committed and retreated to the desert. He believed that a preternatural entity spoke to him there and provided him with Liber 49, which he believed to represent a fourth part of Crowley's The Book of the Law, the primary sacred text of Thelema, as well as part of a new sacred text he called the Book of Babalon. This accomplished, Parsons set about trying to sell the Parsonage for $25,000, on the condition that he could continue to live in the coach house, and he appointed Roy Leffingwell to head the Agape Lodge, which would now have to meet elsewhere for its rituals.
Parsons decided to co-found a company called Allied Enterprises with Hubbard and Sara, into which Parsons invested his life savings of $20,970. Hubbard suggested that with this money they travel to Miami to purchase three yachts, which they would then sail through the Panama Canal to the West Coast, where they could sell them on for a profit. Parsons agreed, but many of his friends thought it was a bad idea. Hubbard had requested permission from the U.S. Navy to sail to China and South and Central America on a mission to "collect writing material": his real plans were for a world cruise. Parsons was incensed when he discovered that Hubbard and Sara had left for Miami with $10,000 of the money; he suspected a scam but was placated by a telephone call from Hubbard and agreed to remain business partners. When Crowley, in a telegram to Germer, dismissed Parsons as a "weak fool" and victim to Hubbard and Sara's obvious confidence trick, Parsons changed his mind, flew to Miami and placed a temporary injunction and restraining order on them. Upon tracking them down to a harbor in County Causeway, Parsons discovered that the couple had purchased three yachts with his money; they tried to flee aboard one but hit a squall and were forced to return to port. Parsons was convinced that he had brought them to shore through a lesser banishing ritual of the pentagram containing a geomantic invocation of Bartzabel—a spirit Mars. Allied Enterprises was dissolved; in a court settlement Hubbard was made to promise to reimburse Parsons. Parsons was discouraged from taking further action by Sara, who threatened to report him for statutory rape since their sexual relationship took place when she was under 18—below California's age of consent. Parsons was ultimately compensated with only $2,900. Hubbard later married Sara, making him a bigamist because he was already married to Margaret "Polly" Grubb. Hubbard went on to found Dianetics and Scientology.
The Sunday Times published an article about Hubbard's involvement with the OTO and Parsons' occult activities in December 1969. In response, the Church of Scientology released an unsubstantiated press statement which said that Hubbard had been sent as an undercover agent by the U.S. Navy to intercept and destroy Parsons' "black magic cult", and save Sara from its influence. The Church also claimed that Robert A. Heinlein was the clandestine Navy operative who "sent in" Hubbard to undertake this operation. Returning to California, Parsons completed the sale of the Parsonage, which was then demolished, and resigned from the OTO. He wrote in his letter to Crowley that he did not believe that "as an autocratic organization, [the OTO] constitutes a true and proper medium for the expression and attainment" of the Thelemic rites of humanity.
Parsons obtained employment with North American Aviation at Inglewood, where he worked on the Navaho Missile Program. Cameron and Parsons moved into a house on Manhattan Beach, where he began to teach her more about occultism. They were married on October 19, 1946, four days after his divorce from Helen was finalized, with Forman as their witness. He continued to be seen as a specialist in rocketry; he acted as an expert consultant in numerous industrial tribunals and police investigations regarding explosions. In May 1947, Parsons gave a talk at the Pacific Rocket Society in which he predicted that rockets would take humans to the Moon. Although he had become distant from the now largely defunct OTO—with Jane Wolfe unsuccessfully appealing for him to rejoin—and had sold much of his Crowleyan library, he continued to correspond with Crowley until the latter's death in December 1947.
At the emergence of the Cold War, a Red Scare developed in the U.S. as the Congressional House Un-American Activities Committee began investigating people with perceived communist sympathies. Sensing that scientists were scapegoats of this anti-communist sentiment, Parsons expressed his disdain that "Science, that was going to save the world in H. G. Wells' time is regimented, straight-jacked, [and] scared shitless". Many of his former colleagues lost their security clearances and jobs as a result, and eventually the FBI stripped Parsons of his clearance because of his past communist associations—despite his insistence of being "an individualist" rather than a Marxist—and because of his advocacy of "sexual perversion" in the OTO—leaving him unemployed. He speculated in a June 1949 letter to Germer that his clearance was revoked in response to his dissemination of Crowley's Liber OZ, a 1941 tract summarizing the individualist moral principles of Thelema. In reaction to this hostile treatment, Parsons sought work in the rocket industry abroad. He sought advice to do so in correspondence with von Kármán; whose advice he followed by enrolling in an evening course in advanced mathematics at USC to bolster his employability in the field—but again he neglected attendance and failed the course. Parsons managed to earn a wage as a car mechanic, a manual laborer at a gas station, a hospital orderly, and for two years he was a faculty member at the USC Department of Pharmacology. Relations between Parsons and Cameron became strained; they agreed to a temporary separation. She moved to Mexico to join an artists' commune in San Miguel de Allende.
Unable to pursue his scientific career, without his wife and devoid of friendship, Parsons decided to return to occultism and embarked on sexually-based magical operations with prostitutes. He was intent on performing "the Crossing of the Abyss", attaining union with the universal consciousness and becoming "the Master of the Temple". Following his apparent success in doing so, Parsons recounted having an out-of-body experience invoked by Babalon, who astrally transported him to the biblical City of Chorazin. Part of Parsons' "Oath of the Abyss" was an "Oath of the AntiChrist", which was witnessed by Wilfred Talbot Smith. In this oath, Parsons professed to embody an entity named Belarion Armillus Al Dajjal, "who am come [sic] to fulfill the law of the Beast 666 [Aleister Crowley]". Viewing these oaths as the completion of the Babalon Working, Parsons wrote an autobiography titled Analysis by a Master of the Temple and an occult text titled The Book of AntiChrist. In the latter work, Parsons—writing as Belarion—prophesied that in seven years—on the condition that he lived—Babalon would manifest on Earth, superseding the Abrahamic religions and converting the world to Thelema. Following Parsons' death, Cameron said that Babalon was successfully manifested in her person. Reinforcing his protestations about the OTO, Parsons describes it as "an excellent training school for adepts, but hardly an appropriate Order for the manifestation of Thelema".
During this period, Parsons also wrote an essay on his individualist philosophy and politics—which he described as standing for "liberalism and liberal principles"—titled "Freedom is a Two-Edged Sword". Neither of these works were published in his lifetime. Through Heinlein, Parsons received a visit from writer L. Sprague de Camp, with whom he discussed magic and science fiction, and disclosed that Hubbard had sent a letter offering him Sara back. De Camp later referred to Parsons as "An authentic mad genius if I ever met one", and based the character Courtney James on him in his time travel story A Gun for Dinosaur (1956). Parsons entered a brief relationship with an Irishwoman named Gladis Gohan; they moved to a house on Redondo Beach, a building known by them as the "Concrete Castle". Cameron returned to Redondo Beach from San Miguel de Allende and violently argued with Parsons upon discovering his infidelity, before she again left for Mexico. Parsons responded by initiating divorce proceedings against her on the grounds of "extreme cruelty".
Through his connections, Parsons had his security clearance reinstated by the Industrial Employment Review Board, which ruled that there was insufficient evidence that he had ever had communist sympathies. This allowed Parsons to obtain a contract in designing and constructing a chemical plant for the Hughes Aircraft Company in Culver City. Von Kármán put Parsons in touch with Herbert T. Rosenfeld, President of the Southern Californian chapter of the American Technion Society—a Zionist group dedicated to supporting the newly-created state of Israel. Rosenfeld offered Parsons a job with the Israeli rocket program and hired him to produce reports for them. As the Red Scare intensified, Parsons decided to migrate to Israel to pursue Rosenfeld's offer, but a Hughes secretary, whom Parsons had asked to type up a portfolio of technical documents, reported him to the FBI. She accused Parsons of espionage and attempted theft of classified company documents on the basis of some of the reports that he had sought to submit to the Technion Society. Parsons was immediately fired from Hughes; the FBI investigated the complaint and were suspicious that Parsons was spying for the Israeli government. Parsons denied the allegations when interrogated; he insisted that his intentions were peaceful and had suffered an error of judgment in procurement of the documents. Some of Parsons' scientific colleagues rallied to his defense, but the case against him worsened when the FBI investigated Rosenfeld for being linked to Soviet agents, and more accounts of his occult and sexually permissive activities at the Parsonage came to light. In October 1951 the U.S. attorney decided that because the contents of the reports did not constitute state secrets, Parsons was not guilty of espionage.
The Review Board, however, still considered Parsons a liability because of his historical Marxist affiliations and investigations by the FBI, and in January 1952 they permanently reinstated their ban on him working for classified projects, effectively prohibiting him from working in rocketry. In May 1951 he founded the Parsons Chemical Manufacturing Company, based in North Hollywood, and also began work at the Bermite Powder Company in Saugus, where he created pyrotechnics and explosives such as fog effects and imitation gunshot wounds for the film industry. Cameron and Parsons reconciled and resumed their relationship, moving into a former coach house on South Orange Grove Boulevard. Parsons converted its large, first-floor laundry room into a home laboratory to work on his chemical and pyrotechnic projects, homebrew absinthe and stockpile his materials. They let out the upstairs bedrooms and began holding parties that were attended largely by bohemians and members of the Beat Generation, along with old friends including Forman, Malina and Cornog. Though Parsons in his mid-thirties was a "prewar relic" to the younger attendees, the raucous socials often lasted until dawn and frequently attracted police attention. Parsons also founded a new Thelemite group known as "The Witchcraft", whose beliefs revolved around a simplified version of Crowley's Thelema and Parsons' own Babalon prophecies. He offered a course in its teachings for a ten dollar fee and formulated a new Thelemic belief system called "The Gnosis", a version of Christian Gnosticism with Sophia as its godhead and the Christian God as its demiurge.
Parsons and Cameron decided to travel to Mexico for a few months, both for a vacation and for Parsons to take up a job opportunity establishing an explosives factory for the Mexican government. They hoped that this would facilitate a move to Israel, where they could start a family.
On June 17, 1952, a day before their planned departure, Parsons received a rush order of explosives for a film set and began to work on it in his home laboratory. An explosion destroyed the lower part of the building, during which Parsons sustained mortal wounds. His right forearm was amputated, his legs and left arm were broken and a hole was torn in the right side of his face. Despite these critical injuries, Parsons was found conscious by the upstairs lodgers. He tried to communicate with arriving emergency service personnel, who rushed him to the Huntingdon Memorial Hospital, where he was declared dead around thirty-seven minutes after the explosion. When his mother, Ruth, was informed of the events, she immediately committed suicide by taking an overdose of barbiturates.
Pasadena Police Department criminologist Don Harding led the official investigation; he concluded that Parsons had been mixing fulminate of mercury in a coffee can when he dropped it on the floor, causing the initial explosion, which worsened when it came into contact with other chemicals in the room. Forman considered this likely, stating that Parsons often had sweaty hands and could easily have dropped the can. Some of Parsons' colleagues rejected this explanation, saying that he was very attentive about safety. Two colleagues from the Bermite Powder Company described Parsons' work habits as "scrupulously neat" and "exceptionally cautious". The latter statement—from chemical engineer George Santymers—insisted that the explosion must have come from beneath the floorboards, implying an organized plot to kill Parsons. Harding accepted that these inconsistencies were "incongruous" but described the manner in which Parsons had stored his chemicals as "criminally negligent". The police saw insufficient evidence to continue the investigation and closed the case as an accidental death.
Both Wolfe and Smith suggested that Parsons' death had been suicide, stating that he had suffered from depression for some time. Others theorized that the explosion was an assassination planned by aerospace magnate Howard Hughes in response to his suspicion that Parsons had stolen Hughes Aircraft Company documents. Cameron became convinced that Parsons had been murdered—either by police officers seeking vengeance for his role in the conviction of Earl Kynette or by anti-Zionists opposed to his work for Israel. One of Cameron's friends, the artist Renate Druks, later stated her belief that Parsons had died in a rite designed to create a homunculus. His death has never been definitively explained.
The immediate aftermath of the explosion attracted the interest of the U.S. media, making headline news in the Los Angeles Times. These initial reports focused on Parsons' prominence in rocketry but neglected to mention his occult interests. When asked for comment, Aerojet secretary-treasurer T.E. Beehan said that Parsons "liked to wander, but he was one of the top men in the field". However, within several days, journalists had discovered his involvement in Thelema and emphasized this of their reports.
A private prayer service was held for Parsons at the funeral home where his body was cremated. Cameron scattered his ashes in the Mojave Desert, before burning most of Parsons' possessions. She later tried to perform astral projection to commune with him, and performed blood rituals from which she claimed a new Thelemic entity named Hilarion originated. The OTO also held a memorial service—with attendees including Helen—at which Smith led the Gnostic Mass.
Although considered effeminate as a child, in adult life Parsons was known to exhibit an attitude of machismo. His FBI file described him as "potentially bisexual", and Carter noted that he "once expressed a latent homosexuality", although he also accepted that the impression of bisexuality given by Parsons may have been erroneous. He gained the reputation of being a womanizer, and enjoyed sexual relationships with many women; he was notorious for frequently flirting and having sexual liaisons with female staff members at JPL and Aerojet. Aside from rocketry, Parsons often hunted jack rabbits and cotton tails in the desert. He also enjoyed playing pranks on his colleagues, often through detonating explosives such as firecrackers and smoke bombs, and was also known to spend hours at a time in the bathtub playing with toy boats while living at the Parsonage.
As well as intense bursts of creativity, Parsons was known to suffer from severe mood swings causing fits of rage and bouts of melancholy. His father Marvel, after suffering a near-fatal heart attack, died as a psychiatric patient at St. Elizabeths Hospital in Washington D.C. diagnosed with severe clinical depression, a condition Pendle suggested Parsons inherited.
Parsons adhered to the occult philosophy of Thelema, which had been founded in 1904 by the English occultist Aleister Crowley following a spiritual revelation that he had in the city of Cairo, Egypt, when—according to Crowley's own accounts—a spirit being known as Aiwass dictated to him a prophetic text known as The Book of the Law.  During rocket tests, Parsons often recited Crowley's poem "Hymn to Pan" as a good luck charm.
In July 1945 Parsons gave a speech to the Agape Lodge, in which he attempted to explain how he felt that The Book of the Law could be made relevant to "modern life". In this speech, which was subsequently published under the title of "Doing your Will", he examined the Thelemite concept of True Will, writing that:
Parsons identified four obstacles that prevented humans from achieving and performing their True Will, all of which he connected with fear: the fear of incompetence, the fear of the opinion of others, the fear of hurting others, and the fear of insecurity. He insisted that these must be overcome, writing that "The Will must be freed of its fetters. The ruthless examination and destruction of taboos, complexes, frustrations, dislikes, fears and disgusts hostile to the Will is essential to progress."
Though Parsons was a lifelong devotee to Thelema, he grew weary of and eventually left the Ordo Templi Orientis—the religious organization that began practicing Thelema under Crowley's leadership from the 1910s—which Parsons viewed, despite the disagreement of Crowley himself, as excessively hierarchical and impeding upon the rigorous spiritual and philosophical practice of True Will. In this sense Parsons was described by Carter as an "almost fundamentalist" Thelemite who placed The Book of the Law's dogma above all other doctrine.
From early on in his career, Parsons took an interest in socialism and communism, views that he shared with his friend Malina. Under the influence of another friend, Sidney Weinbaum, the two joined a communist group in the late 1930s, with Parsons reading Marxist literature, but he remained unconvinced and refused to join the American Communist Party. Malina asserted that this was because Parsons was a "political romantic", whose attitude was more anti-authoritarian than anti-capitalist. Parsons would later become critical of the Marxist-Leninist government of the Soviet Union led by Joseph Stalin, sarcastically commenting:
During the era of McCarthyism and the Red Scare in the early 1950s, he was questioned as to his former links to the communist movement, by which time he denied any connection to it, instead describing himself as "an individualist."
Influenced by Thelema, which holds to the ethical code of "Do what thou wilt", Parsons became a vocal social libertarian in the 1940s. In his article "Freedom is a Lonely Star", he championed the libertarian social views of some of the Founding Fathers of the United States that were enshrined in the American Constitution, claiming that by his own time these had been "sold out by America, and for that reason the heart of America is sick and the soul of America is dead." He proceeded to criticize many aspects of contemporary U.S. society, particularly the police force, remarking that "The police mind is usually of a sadistic and homicidal trend" and noting that they carried out the "ruthless punishment of symbolic scapegoats" such as African-Americans, prostitutes, alcoholics, homeless people and socio-political radicals, under the pretense of a country that had "liberty and justice for all."
To bring about a freer future Parsons believed in liberalizing attitudes to sexual morality stating that, in his belief, the publication of the Kinsey report and development of the psychonautical sciences had as significant an influence on Western society as the creation of the atomic bomb and the development of nuclear physics. He also believed that in the future the restrictions on sexual morality within society should be abolished in order to bring about greater freedom and individuality. In this context, Colin Bennett of the Fortean Times cites Parsons as one of the instigators of the countercultural movements of the 1960s. Jack Cashill concurred with this assessment, arguing that "Although his literary career never got much beyond pamphleteering and an untitled anti-war, anti-capitalist manuscript", Parsons played a significant role—greater than that of Church of Satan founder Anton LaVey—in shaping the Californian counterculture of the 1960s and beyond through his influence on contemporaries such as Hubbard and Heinlein,  while religious studies scholar Hugh B. Urban credits Parsons' "Witchcraft" group as helping to precipitate the neopagan revival of the 1950s.
Robert Anton Wilson described Parsons as an "ultra-individualist" who exhibited a "genuine sympathy for working people", strongly empathized with feminism and held an antipathy toward patriarchy. Parsons identified as a liberal in "Freedom is a Two-Edged Sword", but Wilson argued that he was more closely aligned to the American libertarian and anarchist movements of the 20th century. Parsons was also a Zionist, and was supportive of the creation of the State of Israel, making plans to emigrate there when his military security clearance was revoked.
In the decades following his death, Parsons would be better remembered among the Western esoteric community rather than their scientific counterpart. For instance, English Thelemite Kenneth Grant suggested that Parsons' Babalon Working marked the start of the appearance of flying saucers in the skies, leading to phenomena such as the Roswell UFO incident and Kenneth Arnold UFO sighting. Cameron herself postulated that the 1952 Washington, D.C. UFO incident was a spiritual reaction to Parsons' death. In 1954 she portrayed Babalon in Thelemite Kenneth Anger's short film Inauguration of the Pleasure Dome, viewing this cinematic depiction as ritualistically aiding the literal invocation of Babalon begun by Parsons' working.
In December 1958 the Jet Propulsion Laboratory (JPL) was integrated into the newly established National Aeronautics and Space Administration, after having built the Explorer 1 satellite that commenced America's Space Race with the Soviet Union. In a letter to Malina the same year, von Kármán ranked Parsons first in a list of figures he viewed as most important to modern rocketry and the foundation of the American space program. According to Richard Metzger, Wernher von Braun—who was nicknamed "The Father of Rocket Science"—once argued that Parsons was more worthy of this moniker. In October 1968 Malina gave a speech at JPL in which he highlighted Parsons' contribution to the U.S. rocket project, and lamented how it had come to be neglected, crediting him for making "key contributions to the development of storable propellants and of long duration solid propellant agents that play such an important role in American and European space technology." Encyclopedia Astronautica states that these innovations "led to all solid-fuel rockets in use in the 21st century."
In October 1986 JPL held an open access event to mark the 50th anniversary of its foundation—which featured a "nativity scene" of mannequins reconstructing the Halloween 1936 photograph of the GALCIT Group—and erected a monument commemorating their first rocket test. Among the aerospace industry, JPL was nicknamed as standing for "Jack Parsons' Laboratory" or "Jack Parsons Lives". The International Astronomical Union decided to name a crater on the far side of the Moon Parsons after him in 1972. Many of Parsons' writings would see posthumous publication as Freedom is a Two-Edged Sword in 1989. The Cameron-Parsons Foundation was founded as an incorporated company in 2006, with the intention of conserving and promoting Parsons' writings and Cameron's artwork, and in 2014 Fulger Esoterica published Songs for the Witch Woman—a limited edition book of poems by Parsons with illustrations by Cameron, released to coincide with his centenary.
In 1999 Feral House published the biography Sex and Rockets: The Occult World of Jack Parsons by John Carter, who expressed the opinion that Parsons had accomplished more in under five years of research than Robert H. Goddard had in his lifetime, and noted that his role in the development of rocket technology had been neglected by historians of science; conversely, Carter thought that Parsons' abilities and accomplishments as an occultist had been overestimated and exaggerated among Western esotericists. Feral House republished the work as a new edition in 2004, accompanied with an introduction by the occultist and author Robert Anton Wilson. Wilson believed that Parsons was "the one single individual who contributed the most to rocket science", describing him as being "very strange, very brilliant, very funny, [and] very tormented", and considering it noteworthy that the day of Parsons' birth was the predicted beginning of the apocalypse advocated by Charles Taze Russell, the founder of the Jehovah's Witness movement.
A second biography of Parsons was published in 2005 through Weidenfeld & Nicolson with the title Strange Angel: The Otherworldly Life of Rocket Scientist John Whiteside Parsons; it was authored by George Pendle, who described Parsons as "the Che Guevara of occultism" (with Metzger similarly describing him as "the James Dean of occultism"), and noted that although Parsons "would not live to see his dream of space travel come true, he was essential to making it a reality." Pendle considered that the cultural stigma attached to Parsons' occultism was the primary cause of his low public profile, noting that "Like many scientific mavericks, Parsons was eventually discarded by the establishment once he had served his purpose." It was this unorthodox mindset, creatively facilitated by his science fiction fandom and "willingness to believe in magic's efficacy", Pendle argued, "that allowed him to break scientific barriers previously thought to be indestructible"—later commenting that Parsons "saw both space and magic as ways of exploring these new frontiers—one breaking free from Earth literally and metaphysically." L. Ron Hubbard's role in Parsons' Agape Lodge—and the ensuing yacht scam—was explored in Russell Miller's 1987 Hubbard biography Bare-faced Messiah, which was met by legal challenges from the Church of Scientology. Parsons' involvement in the Agape Lodge would also be discussed by Martin P. Starr in his history of the American Thelemite movement, The Unknown God: W.T. Smith and the Thelemites, published by Teitan Press in 2003.
Before his death, Parsons appeared in science fiction writer Anthony Boucher's murder-mystery novel Rocket to the Morgue (1942) under the guise of Hugo Chantrelle. Another fictional character based on Parsons was Courtney James, who features in L. Sprague de Camp's 1956 work A Gun for Dinosaur. Pasadena Babalon, a stage play about Parsons written by George D. Morgan and directed by Brian Brophy, premiered at Caltech as a production by its theater Arts Group in 2010, and that same year Cellar Door Publishing released Richard Carbonneau and Robin Simon Ng's graphic novel, The Marvel: A Biography of Jack Parsons. In 2012 the Science Channel broadcast a documentary dramatization titled Magical Jet Propulsion in an episode of its Dark Matters: Twisted But True television series—in which Parsons was portrayed by English actor Adam Howden—while independent record label Drag City released Parsons' Blues, an instrumental tribute single by experimental rock act Six Organs of Admittance. In 2014 AMC Networks announced plans for a serial television dramatization of Parsons' life titled Strange Angel, with Ridley Scott and David Zucker set to be its executive producers.