Ernst Julius Öpik (1893–1985)
Ernst Öpik was an Estonian astronomer
who moved to Armagh Observatory, Northern Ireland, in 1948 and
remained there for the rest of his life. His speciality was the
minor bodies of the Solar System – asteroids, comets, and
meteors – which at the time were an unfashionable area of
study. In 1932 he proposed that comets originate in a cloud
orbiting at the edge of the Solar System; this is now known as
the Oort Cloud, after the Dutch astronomer Jan Oort who revived
the idea. His grandson Lembit Öpik is now a Member of
Parliament and has helped draw attention to the dangers posed
to the Earth by collisions with asteroids.
1986 Mauritania
Öpik appeared on one of the four
members of a Halley’s Comet set issued by the African
republic of Mauritania in 1986. In the foreground is one of the
twin Russian Vega probes heading for the comet’s nucleus,
with the European Giotto probe in the distance towards the top.
Stanley Gibbons no. 866
1995 Mali
In 1995 the African republic of Mali issued
a series of stamps commemorating various anniversaries and
events. The lowest value member of the set recalled the impact
of Comet Shoemaker–Levy 9 with Jupiter the previous year.
Also shown is NASA’s Galileo probe which arrived at
Jupiter at the end of 1995, with Öpik above.
Stanley Gibbons no. 1359