Thomas George Cowling

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Thomas George Cowling (born June 17, 1906 in Walthamstow , Essex / England, † June 16, 1990 ) was a British astronomer and mathematician .

life and work

He studied from 1924 on a scholarship at Brasenose College, Oxford University , where he graduated in mathematics with top marks in 1927. From 1928 to 1930 he was the first student of the astrophysicist Edward Arthur Milne .

He then worked for three years at Imperial College London as assistant to Sydney Chapman and then taught at the universities of Swansea (Assistant Lecturer from 1933), Dundee (Lecturer from 1937), Manchester (Lecturer from 1939) and Bangor , where he from 1945 Was a professor. In 1948 he moved to Leeds University as a professor and stayed there until his death, even though he officially retired in 1970.

As assistant to Sydney Chapman, he wrote a well-known monograph on the statistical mechanics of gases, first published in 1939.

He was mainly active in the field of stellar astrophysics and was considered a specialist in the internal structure of stars. In the 1930s he developed a stellar model named after him in which the internal energy was not transported by radiation, as was usually assumed at the time, but by convection in the inner core. Also in the 1930s, independently of Ludwig Biermann , he developed improved boundary conditions for star models similar to the sun, in which convection prevailed outside, but energy was transported on the surface again by radiation (which was taken into account in the boundary conditions).

Cowling also dealt with magnetohydrodynamics , about which he wrote a textbook. In 1933 he showed that the magnetic fields in sunspots, for example, need a dynamo mechanism to generate them, otherwise they would have long since died down. At the same time he showed that the fields generating them could not be axially symmetrical, thereby refuting a hypothesis by Joseph Larmor . Examples of non-axially symmetric dynamo fields, for example for the earth's magnetic field or the magnetic fields of sunspots, were only found much later. In 1945, on the other hand, he showed that some magnetic fields, especially in very massive stars, can have a lifespan that exceeds the lifespan of the star itself. He is also known for his work on non-radial oscillations in stars.

Awards

He had been a Fellow of the Royal Society since 1947. From 1931 he was a member and from 1965 to 1967 President of the Royal Astronomical Society.

Fonts

  • Magnetohydrodynamics , Interscience 1957, 2nd edition, Hilger 1977
  • with Sydney Chapman : Mathematical theory of nonuniform gases , Cambridge University Press 1939, 1952, 1970
  • Molecules in motion , Hutchinson´s University Library, London, New York 1950
  • with Horace Babcock General magnetic fields in the sun and in the stars , Monthly Notices Royal Astronomical Society, Volume 113, 1953, pp. 357-381, online
  • Solar electrodynamics , in Gerard Peter Kuiper (Editor) The Sun , University of Chicago Press 1953
  • Magnetic Stars , in LH Aller , DB MacLaughlin Stellar Structure , University of Chicago Press 1965

literature

Web links

Individual evidence

  1. ^ Cowling The magnetic field of sunspots , Monthly Notices Royal Astronomical Society, Volume 94, 1933, pp. 39-48, online
  2. ↑ Cowling On the Sun's general magnetic field , Monthly Notices Royal Astronomical Society, Vol 105, 1945, pp 166, online
  3. ^ Cowling The non radial oscillations of polytropic stars , Monthly Notices Royal Astronomical Society, Volume 101, 1941, p. 367, online
personal data
SURNAME Cowling, Thomas George
BRIEF DESCRIPTION British astronomer and mathematician
DATE OF BIRTH June 17, 1906
PLACE OF BIRTH Walthamstow , Essex , England
DATE OF DEATH June 16, 1990