World War II. Comet 85D/Boethin was quite faint for a visual discovery, which had been made possible only by the very dark skies of Abra province. Observers with telescopes much larger than Boethin's had difficulties to see the object. Marsden noted that this was also true for Boethin's earlier reports from 1973, probably contributing to the unsuccessful confirmation in that case. He offered a free subscription to the IAU Circulars, expressing his hope that Boethin could use the money saved from the subscription to pay for telegrams in case of future discoveries. Boethin never found a new comet again. In 2003, Gary Kronk and Brian Marsden noticed that the object that Leo Boethin observed in 1973 was actually 104P/Kowal 2, which had not been officially discovered until 1979. From Boethin's report, it was apparent that comet Kowal 2 had been in a short, major outburst in 1973. Orbit 85D/Boethin was a Jupiter-family comet with an orbital period of 11.81 years and a moderate inclination of 4.3°. It had been captured in a 1:1 orbital resonance with Jupiter for at least the last couple of centuries. At the time of its discovery, it was only the second object known to be in such resonance, after 56P/Slaughter–Burnham. It has been suggested that comets in this resonance might originate from the Jupiter trojans. 85D/Boethin came within 0.63 AU of Jupiter in August 1995. Target of EPOXI mission, loss of comet It was to be a target of NASA's EPOXI comet-exploration mission in December 2008; however, the comet was not recovered in time to set up the trajectory for the flyby with sufficient accuracy, and EPOXI switched to its backup target Hartley 2. It is thought that 85D/Boethin may have broken into pieces too small for visual detection. As a result, its designation was changed from 85P to 85D on 9 June 2017, signifying that it has been lost and has possibly broken up. References External links Orbital simulation from JPL (Java) / Horizons Ephemeris 85D/Boethin – Seiichi Yoshida @ aerith.net 85P past, present and future orbital elements Destination: Missing--Comet Once Targeted by NASA Mission Vanished (Scientific American – October 23, 2012) "Deep Impact Flyby Spacecraft Ready For New Mission" (from space.com, July 14, 2005) Periodic comets 0085 Lost comets 085P 19750104