Hostname: page-component-cd9895bd7-7cvxr Total loading time: 0 Render date: 2024-12-26T15:21:04.249Z Has data issue: false hasContentIssue false

IV. The Abundances of the Chemical Elements in the Universe

Published online by Cambridge University Press:  25 April 2016

M. Minnaert
Affiliation:
Astronomical Observatory, Utrecht, Netherlands

Extract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

The analysis of the Sun by spectroscopic methods refers to an exceedingly thin layer, just above the photosphere, which has a thickness of only a few hundreds of kilometers. The deeper layers are inaccessible to our investigations, because there the matter becomes too opaque. The higher layers of the chromosphere and the corona again are less well known, because they are too transparent, so that deviations from thermodynamic equilibrium conditions may occur. So it is understandable that just the layer where the equilibrium is nearly established must be the only layer which can be fully investigated. Probably this is the best analysed sample of the universe. Whether the composition here found is really representative for the Sun as a whole depends on the importance of the convection, which tends to stir the gases into one homogeneous mixture.

Type
Part IV. Symposia
Copyright
Copyright © Cambridge University Press 1950

References

(1) Bowen, . P.A.S.P. 60, 16, 1948.Google Scholar
Cabannes, and Dufay, . C.R. 226, 1569, 1948.Google Scholar
(2) Dahme, . Zs.f. Ap. 11, 93, 1935.Google Scholar
(3) Goldberg, and Aller, . Atoms, Stars and Nebulae, p. 114, 1943.Google Scholar
(4) Minnaert, . B.A.N. 10, 399, 1940 and 10, 339, 1947.Google Scholar
(5) Rosenthal, . Nat. 134, 533, 1934.CrossRefGoogle Scholar
(6) Russell, . Ap. J. 70, 11, 1929.Google Scholar
(7) Strömgren, . Strömgren Festschrift, p. 218, 1940.Google Scholar
(8) Unsöld. ZS. f. Phys. 59, 353, 1930.Google Scholar
(9) Unsöld. ZS. f. Ap. 24, 22, 1947.Google Scholar
(10) Unsöld. ZS. f. Ap. 24, 306, 1948.CrossRefGoogle Scholar
(11) Hunaerts, . Ann. Ap. 10, 237, 1947.Google Scholar
(12) Rudkjøbing, . P.o.M. København, no. 140, 1945.Google Scholar
(13) Wildt, . Ap. J. 105, 36, 1947.Google Scholar
(14) Brück, and Moss, . M.N. 105, 17 and 282, 1945.Google Scholar