Friedrich Georg Wilhelm von Struve (Russian: Василий Яковлевич Струве, trans. Vasily Yakovlevich Struve; 15 April 1793 – 23 November [O.S. 11 November] 1864) was a Baltic Germanastronomer and geodesist. He is best known for studying double stars and initiating a triangulation survey later named Struve Geodetic Arc in his honor.
In 1808 he entered the University of Tartu (Dorpat), where he first studied philology, but soon turned his attention to astronomy. From 1813 to 1820, he taught at the university and collected data at the Tartu Observatory, and in 1820 became a full professor and director of the observatory. His teachings have had a strong effect that is still felt at the university.[3][4][5]
Struve's name is best known for his observations of double stars, which he carried on for many years. Although double stars had been studied earlier by William Herschel, John Herschel and Sir James South, Struve outdid any previous efforts. While at Dorpat he obtained in 1824 a refracting telescope with an aperture of 23 cm (about 9 inches) made by Joseph von Fraunhofer, said to be a masterpiece of optical and mechanical quality.[10] With this telescope Struve discovered a very large number of double stars. In 1827 published his double star catalogue Catalogus novus stellarum duplicium.[5] Stars of his catalogue are sometimes indicated by the Greek letter sigma, Σ. Thus, 61 Cygni is also designated as Σ2758.
Since most double stars are true binary stars rather than mere optical doubles (as William Herschel had been the first to discover), they orbit around their common barycenter and slowly change position over the years. Thus Struve made micrometric measurements of 2714 double stars from 1824 to 1837 and published these in his work Stellarum duplicium et multiplicium mensurae micrometricae.[5]
Struve carefully measured the "constant of aberration" in 1843. He was also the first to measure the parallax of the star Vega, although Friedrich Bessel had been the first to measure the parallax of a star (61 Cygni).[5]
In an 1847 work, Etudes d'Astronomie Stellaire: Sur la voie lactee et sur la distance des etoiles fixes, Struve was one of the first astronomers to identify the effects of interstellar extinction (though he provided no mechanism to explain the effect). His estimate of the average rate of visual extinction, 1 mag per kpc, is remarkably close to modern estimates (0.7–1.0 mag per kpc).[5]
Struve was the second of a dynasty of astronomers through five generations. He was the great-grandfather of Otto Struve and the father of Otto Wilhelm von Struve. He was also the grandfather of Hermann von Struve, who was Otto Struve's uncle.
^ abcdefghiA. H. Batten (1977). "The Struves of Pulkovo – A Family of Astronomers". Journal of the Royal Astronomical Society of Canada. 71: 345. Bibcode:1977JRASC..71..345B.