SKETCH OF PROFESSOR OTTO WILHELM STRUVE. 263 

 SKETCH OF PROFESSOR OTTO WILHELM STRUYE. 



By Professor SIMON NEWCOMB. 



OTTO WILHELM STRUVE, now Director of the Pulkowa Ob- 

 servatory, was born at Dorpat, Russia, May 7, 1819. His father 

 was Dr. Wilhelm Struve, Director of the Dorpat Observatory, and one 

 of the most distinguished of European astronomers. While the son Otto 

 was still a youth, the father imbued the Emperor Nicholas, whose con- 

 fidence he enjoyed in a high degree, with the notion of erecting the 

 greatest observatory in the world, and thus adding to the luster of his 

 reign and associating his name with the history of science. Thus arose 

 the great Observatory of Pulkowa, some twelve miles south of St. 

 Petersburg, which has sometimes been called the astronomical capital 

 of the world. The work of erecting the observatory, constructing the 

 instruments, and getting the whole established and at work, occupied 

 the years from 1835 to 1840. On the removal of the family to the new 

 establishment, Otto, although only a little over twenty years of age, 

 commenced work as an assistant to his father. His first serious work 

 was an examination of all the stars in the northern heavens, made with 

 the great refractor, in order to detect new double stars. The result 

 was a catalogue of many hundred double stars, all before unknown, 

 and many very close and difficult. The subject of double stars was 

 one which seemed to belong especially to the Struve family, their 

 observations and measurements having been at Dorpat the great work 

 of the father, who thus became preeminent in this branch of research. 

 His " Mensurae Micrometricse " is one of the standard astronomical 

 works of the century, a book whose magnificent proportions correspond 

 to the labor expended in its preparation. The next considerable work 

 of the son, and one which has been of enduring value, was a deter- 

 mination of the constant of precession, or, to speak more popularly, of 

 the annual amount of motion of the equinox among the stars. His 

 result has been the accepted standard for thirty years, and the work 

 won the gold medal of the Royal Astronomical Society in 1850. 



In 1847 and 1848 he made a series of observations of the satellites 

 of Uranus and Neptune with the great equatorial. His observations 

 of the satellites of Neptune gave the first mass of that planet, which 

 was received with much confidence, but the very unfavorable situation 

 of the planet rendered the result more erroneous than was at first sup- 

 posed. It has since been proved that the observations made about the 

 same time by Bond, at the Harvard Observatory, gave a result much 

 nearer the truth. While on this work he commenced a search for the 

 inner satellites of Uranus, which had been suspected by Sir William 

 Herschel, but have since been proved not to exist. He succeeded, 

 however, in making several observations of what he at the time sup- 

 posed to be a new inner satellite, but did not succeed in getting a suf- 



