In the feature article “Ultracompact Binary Stars” by Gijs Nelemans (Physics Today, July 2006, page 26), box 1 all but declares that stars less than 8 solar masses fuse hydrogen into helium, and that’s it. Not so: Stars with more than about half a solar mass will go on to fuse helium into carbon and oxygen as well. In fact, the accepted picture of an entire class of stars, RR Lyrae variables, consists of stars less massive than the Sun that burn helium in their cores and hydrogen in a shell.
Plenty of readable descriptions of this are available, from basic but clear, 1 to intermediate, 2 to more advanced. 3
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V.
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, New York
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.2.
W. K.
Rose
, Advanced Stellar Astrophysics
, Cambridge U. Press
, New York
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), p. 19
;M.
Harwit
, Astrophysical Concepts
, 2nd ed., Springer
, New York
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), p. 15
.3.
R.
Kippenhahn
, A.
Weigert
, Stellar Structure and Evolution
, Springer
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. © 2007 American Institute of Physics.
2007
American Institute of Physics
