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Bill Chalker

Australian scientist and UAP researcher who investigated Peter Khoury's alleged alien encounters, including DNA analysis of a hair sample recovered from the case.

Anomaly Physical Evidence Group (APEG); invisible college of UFO researchers · Scientist, UAP researcher, author

Bill Chalker is an Australian scientist and researcher of unidentified anomalous phenomena (UAP), trained in mathematics and chemistry, who became the first civilian researcher to gain access to the Royal Australian Air Force’s UAP files in the early 1980s.1 He is best known for his long-running investigation of the alleged alien encounters of Peter Khoury, including forensic DNA analysis of a hair sample said to have been recovered from one of the encounters, published in his book Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions (2005).

Chalker began researching Khoury’s case in 1993, the same year he learned of the 1993 Kelly Cahill case.2 He first heard of Khoury’s 1992 encounter many months after it had occurred,3 and Khoury initially chose not to share details of the experience with him,4 only revealing the full story of the 1992-07-23 Peter Khoury bedroom encounter in 1996.5 Given the significance of the hair evidence, Chalker set out to establish with some certainty that the sample had been obtained the way Khoury described.6 By early 1998 his network of scientific contacts, an informal “invisible college” of researchers who took the UFO phenomenon seriously,13 had expanded to include biochemists, who worked under strict anonymity given the subject’s standing as “forbidden science”.78 This group called itself the Anomaly Physical Evidence Group (APEG), with Chalker acting as its public face.9 The invisible college of UFO researchers discussed using polymerase chain reaction (PCR) amplification and sequencing of mitochondrial DNA on the hair sample.10

Two distinct phases of Deoxyribonucleic Acid (DNA) profiling analysis were carried out on the hair,11 which Chalker states is the only anomalous sample from the case and yielded a strange DNA profile.12 The original analysis confirmed the hair came from someone genetically close to normal humans but of a very unusual racial type.14 Chalker concluded there was no coherent evidence that Khoury had fabricated his account of encountering two women and recovering the hair sample in July 1992.15 The Deoxyribonucleic Acid (DNA) profiling technique used addresses the credibility of claims that alien abductors pursue a genetic agenda.34 Chalker separately DNA-tested a hair sample connected to Mike Wood (mid-north coast New South Wales businessman); it did not display the same anomalies as Khoury’s sample.35 A preliminary mitochondrial DNA PCR comparison found both that sample and one taken from Mike Wood’s daughter to be within the normal human consensus range, though different from one another.36

Chalker’s investigation extended to reconciling apparent inconsistencies in Khoury’s testimony. He wrote to Moira McGhee and Bryan Dickeson requesting a copy of their 1992 McGhee/Dickeson taped interview with Peter Khoury,17 which took several years for McGhee to locate and pass to him.18 Comparing the tape against Khoury’s later hypnotic recollections, Chalker concluded the evidence pointed to two separate encounters with the same two women rather than one, one in October 1991 and one in July 1992.19 Khoury’s hypnotic account of the 1992-07-23 Peter Khoury bedroom encounter was found to be largely consistent with his conscious recollections.20 Chalker played the full taped interview to Peter and Vivian Khoury together to see whether it would trigger further recollection or clarify the 1991-10 Peter Khoury bedroom encounter.21

Chalker’s engagement with the Peter Khoury alien abduction case followed his contact with Kelly Cahill, who first approached him on 1993-10-04 about her encounter.16 He was unable to gain full access to Phenomena Research Australia’s data on the Cahill case and came to regret involving that organisation in the investigation,23 a frustration that Chalker said made him more determined to extract the full potential of the physical evidence in the Khoury case.24 Chalker considered the Cahill case one of the few compelling exceptions to the ambiguity he otherwise found pervading the alien abduction phenomenon,28 saying he generally found physical traces in UFO landing events particularly compelling evidence for the physical reality of UFOs,29 and that most abduction cases he encountered conspicuously lacked compelling physical evidence.30 He has said he works alone on UFO research and works for “the Invisible College”.33

Beyond the Khoury and Cahill cases, Chalker interviewed former student Victor Zakry, who claimed to have seen the Westall object at ground level.37 He also befriended fellow Australian UAP researcher Harry Turner late in Turner’s life.38 Whitley Strieber asked Chalker to investigate a 1976 New South Wales encounter after receiving a letter describing it.25 Chalker interviewed Peter Khoury’s family, including his brother Sam Khoury and their father, while researching his book on the case, recording audio and taking notes but no video.3132 He was also present when Khoury confronted the Skeptics Association (Australia) at the Powerhouse Museum in Sydney.27

  1. First civilian researcher to gain access to RAAF UAP files in the early 1980s; trained in mathematics and chemistry
    “Bill Chalker, an Australian scientist and UAP researcher trained in mathematics and chemistry, was the first civilian researcher to gain access to the Royal Australian Air Force’s UAP files in the early 1980s.”
    In Plain Sight ch9:11178-11381 View the source record →
  2. Began researching Peter Khoury's alleged alien experiences the same year he learned of the Kelly Cahill case (1993)
    “another very striking case came to my notice the same year I began researching Peter’s alien experiences”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch11:226-319
  3. Heard about Peter Khoury's 1992 encounter many months after it occurred
    “Since I heard about Peter's 1992 encounter many months after its occurrence, I wanted to know if what Peter had told other people about this experience was consistent in every detail with what he told me.”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch14:96-297
  4. Peter Khoury initially chose not to share details of his 1992 experience with Chalker
    “Given Peter's experiences with his own group, it hardly seems surprising that he initially chose not to share details of his startling 1992 experience with me.”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch10:9892-10048
  5. Peter Khoury revealed the story to Chalker in 1996
    “After he revealed the story of the women to me in 1996, he said that he had made mention of the experience in his diaries, but because of renovations and building at his house at the time, he was unable to find them for several years. He finally found them in April 1999.”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch10:10706-10972
  6. Needed to establish with some certainty that the hair sample was procured as described, given its significance
    “Because of the significance of the hair evidence, I needed to establish with some degree of certainty that the hair was indeed procured in the way Peter described during his July 1992 experience.”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch10:10509-10693
  7. Chalker's group called itself the Anomaly Physical Evidence Group (APEG), with Chalker as its public face
    “our group, which called itself the Anomaly Physical Evidence Group (APEG),27 decided that I would be the public face of this biochemical variant of the UFO “invisible college.””
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch12:4019-4186
  8. By early 1998 his invisible college circle had expanded to include biochemical scientists
    “by early 1998 my circle of “invisible college” colleagues had expanded to include some scientists from the biochemical field”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch12:3276-3395
  9. The biochemists insisted on strict anonymity given the subject's status as 'forbidden science'
    “They were cautiously interested in UFOs, but mindful of the subject’s stature as “forbidden science,” they insisted that their involvement would need to be conducted strictly on an anonymous basis.”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch12:3403-3594
  10. Discussions focused on PCR amplification and sequencing of mitochondrial DNA from the hair sample
    “Our discussions then focused on the fact that techniques like polymerase chain reaction (PCR) amplification and sequencing of mitochondrial DNA on the hair sample might provide a real challenge to the credibility of abduction stories”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch12:4689-4915
  11. Two distinct phases of DNA analyses were undertaken on the hair sample, yielding a striking array of genetic findings
    “Together, the two distinct phases of DNA analyses undertaken on the "alien hair" sample recovered from Peter Khoury's bizarre 1992 experience provide a very striking array of genetic findings.”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch12:20877-21060
  12. The original analysis confirmed the hair came from someone genetically close to normal humans but of a very unusual racial type
    “And indeed our original analysis confirmed the “alien hair” in the Peter Khoury case came from someone who was genetically close to normal humans, but of a very unusual racial type.”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch15:22054-22230
  13. Chalker states only one anomalous hair sample from Khoury's case exists, with a strange DNA profile
    “But for now we have only this anomalous sample, which has provided us with a strange DNA profile.”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch12:21523-21612
  14. Chalker concludes there is no coherent evidence Khoury fabricated the July 1992 story
    “So we have no coherent evidence that supports a scenario that Peter Khoury fabricated his story of encountering two strange women and recovering a strange hair sample at the same time during July 1992.”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch14:4752-4948
  15. Kelly Cahill first contacted Chalker on 1993-10-04 about her Narre Warren North encounter
    “Kelly Cahill first contacted me back on October 4, 1993, seeking assistance in understanding a bizarre experience she had near the outer Melbourne suburban housing development of Narre Warren North, in the foothills of the Dandenongs, Victoria, between Belgrave and Fountain Gate, during the early hours of August 8, 1993.”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch11:2742-3059
  16. Chalker was unable to gain full access to Phenomena Research Australia's data on the Cahill case and came to regret involving PRA
    “Given my own inability to gain full access to their data on the case, particularly to what seemed provocative physical data, I grew to regret my decision to involve PRA in the first place.”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch11:32488-32670
  17. Frustrations over the Cahill case made Chalker more determined to extract the full potential of the physical evidence in Khoury's case
    “The difficulties and frustrations in gaining full disclosure to the research conducted in Kelly Cahill's case made me more determined than ever to try to extract the full potential of the physical evidence in Peter Khoury's extraordinary abduction encounter.”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch11:35384-35632
  18. Chalker wrote to Moira McGhee and Bryan Dickeson requesting a copy of their taped interview with Khoury
    “To try to clarify this situation, I wrote to both Moira McGhee and Bryan Dickeson, with Peter Khoury's written support, requesting a copy of the tape.”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch14:1207-1352
  19. It took years before McGhee could find, copy and give Chalker the tape
    “It took a few years before Moira was able to find, copy, and give me the tape of their interview with Peter.”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch14:1358-1460
  20. Chalker considers the evidence for two separate encounters with the strange women compelling
    “The evidence for two separate encounters with strange women is compelling. When this interpretation is embraced, the nature of the interactions becomes clearer, and in a way a kind of alien logic or behavior gets laid out for our contemplation.”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch14:48745-48975
  21. Peter Khoury's hypnotic account of the 23 July 1992 experience was largely consistent with his conscious recollections
    “Peter Khoury’s account of the July 1992 experience under hypnosis was largely consistent with his conscious recollections. There are some elaborations of detail and some elements that are new”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch14:37483-37671
  22. Chalker played the whole taped interview for Peter and Vivian Khoury together, to see if it triggered recollections
    “That night I played the whole interview for Peter and Vivian Khoury together, particularly in an effort to see if it triggered any recollections in either, but also to see if any aspect could shed light on the whole dilemma of the tape.”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch14:48010-48241
  23. Chalker has worked with other scientists on the UFO phenomenon within an informal invisible college network
    “Over the years I have been fortunate to work with other scientists on this controversial problem in a sort of "invisible college," an informal network of scientists who view the UFO phenomenon as worthy of serious attention.”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch11:33853-34067
  24. Chalker considers the 1993 Kelly Cahill case one of the few compelling exceptions to the ambiguity pervading the abduction experience
    “One of the few compelling exceptions to the ambiguity and uncertainty that pervade the alien abduction experience is the 1993 Kelly Cahill case.”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch11:1689-1828
  25. Chalker considers physical traces in UFO landing events to be compelling evidence for the physical reality of UFOs
    “Compelling evidence for the physical reality of UFOs comes from physical traces in UFO landing events, so-called EM (electromagnetic) effects in close encounter incidents, particularly car stalling type cases, radar sightings, physical effects on witnesses, and to a lesser extent photographic evidence.”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch11:1103-1397
  26. Chalker found the majority of alien abduction cases conspicuously lacking compelling physical evidence
    “I found the majority of abduction cases conspicuously devoid of compelling physical evidence.”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch11:781-865
  27. UFO Research New South Wales wanted to take over Khoury's abduction support group after Budd Hopkins's October 1992 lecture
    “The group now wanted to take over the abduction support group that had been nurtured principally by Peter Khoury.”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch10:5229-5335
  28. Peter Khoury and Jamie Leonarder formed UFOESA, formalised 14 April 1993
    “Many in the support group left with him, including Leonarder, and together they formed their own group, the UFO Experience Support Association (UFOESA), which was formalized on April 14, 1993.”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch10:7067-7254
  29. Chalker talked to professionals in Khoury's UFOESA group, most of whom recalled him describing the July 1992 experience
    “I talked to a number of these group professionals, and most had some recollection of Peter's telling them about the experience.”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch10:13473-13589
  30. Chalker was surprised how much Jamie Leonarder supported the validity of Khoury's episode
    “Though a rift would eventually develop between them, I was surprised how much Jamie supported the validity of Peter's July 1992 episode.”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch10:12671-12799
  31. Chalker interviewed Khoury's family, including his brother Sam Khoury and their father, while researching a book on Khoury's experiences
    “there's something interesting that happened when, when Bill Chalker was researching the book, he went and spoke to my family... he was speaking to my brother, my oldest brother, Sam, and him and my dad were present.”
    UFO Witness Reveals CHILLING Daytime Alien Encounter - Peter Khoury - DEBRIEFED ep. 58 00:29:48.8-00:30:00.5
  32. Chalker recorded audio and took notes during the interview, with no video recorded
    “we, Bill recorded an audio and took notes, but we didn't get a video of it”
    UFO Witness Reveals CHILLING Daytime Alien Encounter - Peter Khoury - DEBRIEFED ep. 58 00:31:41.0-00:31:45.4
  33. Chalker was present when Khoury confronted the Skeptics Association (Australia) at the Powerhouse Museum, Sydney
    “Look, I took on, Bill was present at the time. Um, it was at the powerhouse museum.”
    UFO Witness Reveals CHILLING Daytime Alien Encounter - Peter Khoury - DEBRIEFED ep. 58 01:38:13.8-01:38:18.3
  34. Chalker works alone on UFO research and works for the Invisible College
    “That's why Bill Chalker works alone. He works for the Invisible College, but that's why they call it the invisible because...”
    UFO Witness Reveals CHILLING Daytime Alien Encounter - Peter Khoury - DEBRIEFED ep. 58 01:36:26.4-01:36:32.3
  35. Whitley Strieber asked Chalker to investigate a 1976 New South Wales encounter
    “He asked me to investigate the experience detailed in the letter, since it had come from Australia.”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch15:1236-1325
  36. The focused DNA profiling technique used in the case addresses the credibility of claims of an alien genetic agenda
    “Therefore, the focused DNA profiling technique we used in the Peter Khoury case goes to the very heart of one of the key claims behind the alleged alien abduction agenda.”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch15:21574-21737
  37. Chalker also DNA-tested a hair sample from the Mike Wood case; it did not show the same anomalies as Khoury's sample
    “It should be noted that the “alien hair” sample obtained in the Peter Khoury case is not the only one we subjected to DNA analysis. There was another alleged “alien hair” sample, but it did not show the kind of anomalies we obtained in Peter’s case.”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch15:28122-28366
  38. Preliminary mitochondrial DNA PCR comparison found both the alien hair and Mike Wood's daughter's hair within the normal human consensus range, though different from each other
    “Ultimately we did the preliminary step of undertaking a mitochondrial DNA PCR profiling comparison against the “human consensus” on both the “alien hair” and Mike’s daughter’s sample. While different, both were within the normal “human consensus” DNA range.”
    Hair of the Alien: DNA and Other Forensic Evidence for Alien Abductions ch15:33177-33428
  39. Chalker interviewed former student Victor Zakry, who claimed to have seen the Westall object at ground level
    “Researcher Bill Chalker also interviewed former student Victor Zakry, who claimed to have seen the object at ground level, close enough to touch it.”
    In Plain Sight ch10:18264-18409 View the source record →
  40. Chalker befriended Harry Turner late in Turner's life
    “He befriended Harry Turner late in his life”
    In Plain Sight ch9:11388-11427 View the source record →

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