Roger Cayrel

Roger Victor Emile Cayrel (born 4 December, 1925, Bordeaux, France) is a French astronomer. His main interests are stellar atmospheres, galactic chemical evolution and metal-poor stars.

He attended the "Lycée Michel-Montaigne" in Bordeaux and studied physics at the École normale supérieure and the "Faculté des sciences de Paris".

Beside his scentific work, he had a number of high-ranking posts in the management of science: director of the Canada-France-Hawaii Telescope (CFHT, 1974-1980), president of the IAU commission on stellar atmospheres (1973-1976) and head of the Bureau des Longitudes (1995-1996).

Cayrel has ben a corresponding member of the Académie des Sciences since 1988.

Cayrel and his colleagues discovered thorium and uranium in the ultra-metal-poor halo star BPS CS31082-0001, which was named Cayrel's Star to honour him. From the thorium and uranium content, an age of 12.5 Billion years could be calculated.

Since 1954, he has been married to the astronomer Giusa de Strobel.

References

* Cayrel, R.; Hill, V.; Beers, T. C.; Barbuy, B.; Spite, M.; Spite, F.; Plez, B.; Andersen, J.; Bonifacio, P.; François, P.; Molaro, P.; Nordström, B.; Primas, F., Measurement of stellar age from uranium decay, Nature, Volume 409, Issue 6821, pp. 691-692 (2001)