Honorary Membership was limited to 10 from 1890-1900, and to 15 from 1901 onwards. Corresponding Membership was a lesser class of Honoris causa membership in the early years. A few honorary members, such as Barnard, were first made corresponding members for a short time before being recommissioned as honorary members.
| Nation(s) |
Start |
End | |
|---|---|---|---|
| Shklovsky, Dr. Iosif S. | USSR | 1966 | 1984 |
| Clemence, Dr. Gerald M. | USA | 1964 | 1974 |
| Schwarzschild, Dr. Martin | USA | 1963 | 1999 |
| van Biesbroeck, Dr. Georges-Achille | Belgium/USA | 1962 | 1974 |
| Plaskett, Prof. Harry H. | Canada/United Kingdom | 1961 | 1979 |
| Woolley, Dr. Richard v.d.R. | United Kingdom/South Africa | 1961 | 1986 |
| Joy, Dr. Alfred H. | USA | 1961 | 1973 |
| Bok, Dr. Bart J. | Holland, USA, Australia | 1961 | 1982 |
| Struvé, Dr. Otto | USA | 1959 | 1963 |
| Ambartsumian, Dr. Viktor Amazaspovitch | USSR/Armenia | 1959 | 1996 |