Occultations of stars by comets,[ 95], [105] [106];
by the moon, [263]
by Mars, [276]
of Jupiter by the moon, [264]
Olbers, Bessel's first patron,[ 29],[ 30];
discoveries of minor planets,[ 74],[ 75]
origin by explosion,[ 75],[ 76]
career,[ 89],[ 90]
Biela's comet,[ 95]
comet of 1811 [ 99]
electrical theory of comets, [100] [104] [324] [347]
multiple tails, [100]
comet of 1819 [101]
cometary coruscations, [105]
November meteors, [329]
Olmsted, radiant of Leonids, [328];
orbit, [329]
Oppenheim, calculation of Schmidt's comet, [363]
Oppolzer, E. von, theory of sun-spots, [159];
variability of Eros, [285]
Oppolzer, Th. von, Winnecke's comet,[ 94];
comet of 1843 [350]
Oxygen in sun, [213]-215;
telluric absorption, [214]
in stars, [384]
Packer, variable stars in cluster, [436]
Palisa, search for Vulcan, [181] [250];
discoveries of minor planets, [283]
Pallas, discovery,[ 74];
inclination of orbit,[ 75], [286]
diameter,[ 75], [287] [288]