Mr. W. M. H. Greaves

Abstract

THE King has approved, on the recommendation of the Secretary of State for Scotland, the appointment of Mr. W. M. H. Greaves, chief assistant of the Royal Observatory, Greenwich, to be astronomer royal for Scotland and professor of astronomy in the University of Edinburgh, in succession to Prof. R. A. Sampson, who retired recently. Mr. Greaves entered St. John‘s opens College, Cambridge, in 1917. He obtained a first class with distinction in Part II of the Mathematical Tripos and was awarded the Tyson Medal for astronomy. He obtained a Smith's Prize in 1921 for an essay on the movement of asteroids of the Trojan group, was awarded an Isaac Newton Studentship and in 1922 was elected a fellow of his College. Mr. Greaves was appointed chief assistant at the Royal Observatory, Greenwich, in 1924. The most important work undertaken by Mr. Greaves at Greenwich has been the development of methods for the determination of the colour temperatures of stars. The observations are divided into two parts: the determination of the relative gradients of the spectral energy curves and the fixing of the zero point of the temperature scale. The determination of the zero point is a long and intricate investigation, requiring reference to a terrestrial source ; it has been undertaken twice with concordant results. The mean colour temperature for stars of spectral type AO was found to be 18,000° K. ; this value is appreciably higher than had previously been accepted but has since been confirmed by other investigators. Mr. Greaves has also been in charge of the magnetic work at Greenwich and has made some valuable investigations of the relationships between sunspots and magnetic storms. Mr. Greaves was secretary to Section A (Mathematics and Physical Science) of the British Association from 1924 until 1931, and has been secretary of the Royal Astronomical Society since 1932.