Past affiliation(s) within the IAU

• Past President of Commission 6 Astronomical Telegrams (1988-1991)
• Past President of Commission 20 Positions & Motions of Minor Planets, Comets & Satellites (1982-1985)
• Past President of Commission 6 Astronomical Telegrams (1976-1979)
• Past Vice-President of Commission 6 Astronomical Telegrams (1985-1988)
• Past Vice-President of Commission 20 Positions & Motions of Minor Planets, Comets & Satellites (1979-1982)
• Past Vice-President of Commission 6 Astronomical Telegrams (1973-1976)
• Past Organizing Committee Member of Commission 6 Astronomical Telegrams (2006-2009)
• Past Organizing Committee Member of Commission 6 Astronomical Telegrams (2003-2006)
• Past Organizing Committee Member of Commission 6 Astronomical Telegrams (2000-2003)
• Past Organizing Committee Member of Commission 6 Astronomical Telegrams (1997-2000)
• Past Organizing Committee Member of Commission 6 Astronomical Telegrams (1994-1997)
• Past Organizing Committee Member of Commission 6 Astronomical Telegrams (1991-1994)
• Past Organizing Committee Member of Commission 20 Positions & Motions of Minor Planets, Comets & Satellites (1985-1988)
• Past Organizing Committee Member of Commission 15 Physical Study of Comets & Minor Planets (1976-1979)
• Past Organizing Committee Member of Commission 20 Positions & Motions of Minor Planets, Comets & Satellites (1976-1979)
• Past Organizing Committee Member of Commission 15 Physical Study of Comets & Minor Planets (1973-1976)
• Past Organizing Committee Member of Commission 20 Positions & Motions of Minor Planets, Comets & Satellites (1973-1976)
• Past Organizing Committee Member of Commission 15 Physical Study of Comets & Minor Planets (1970-1973)
• Past Organizing Committee Member of Commission 20 Positions & Motions of Minor Planets, Comets & Satellites (1970-1973)
• Past Organizing Committee Member of Commission 15 Physical Study of Comets & Minor Planets (1967-1970)
• Past Organizing Committee Member of Commission 15 Physical Study of Comets & Minor Planets (1964-1967)
• Past Member of Division A Fundamental Astronomy (until 2016)
• Past Member of Division B Facilities, Technologies and Data Science (until 2016)
• Past Member of Division F Planetary Systems and Astrobiology (until 2016)
• Past Member of Commission 6 Astronomical Telegrams (1991-2015)
• Past Member of Commission 8 Astrometry (until 2015)
• Past Member of Commission 15 Physical Study of Comets & Minor Planets (until 2015)
• Past Member of Commission 20 Positions & Motions of Minor Planets, Comets & Satellites (until 2015)
• Past Member of Division I Fundamental Astronomy (until 2012)
• Past Member of Division III Planetary Systems Sciences (until 2012)
• Past Member of Division XII Union-Wide Activities (until 2012)