On June 26–27, 1959, Anglican missionary Father William Gill and 37 witnesses at Boianai mission, Papua New Guinea, observed a large disc hovering over the station on consecutive nights. Human-like figures were seen on the craft's upper surface and responded to the witnesses' waves.

Gill's written diary, corroborated by signed statements from named witnesses including teachers Stephen Moi and Ananias Rarata, described a circular object with four legs hovering as low as 100 meters. The RAAF interviewed Gill on December 29, 1959, through Squadron Leader F.A. Lang, concluding the objects were planets Jupiter, Saturn, and Mars, a finding Gill publicly rejected. In 1973, Dr. J. Allen Hynek located six surviving witnesses in Australia and Papua New Guinea, all of whom confirmed Gill's account.