Wanted: Astrometric and Photoelectric Observations of Gamma Virginis and Zeta Herculis

Volume 21 number 1 (1992)

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Dorrit Hoffleit

Yale University, New Haven, CT 06511

Abstract

Gamma Virginis and Zeta Herculis are both binary stars discovered by William Herschel. In 1836 one component of gamma Virginis was observed to have eclipsed the other in 1795 and 1826-31. Modern orbits for these binaries suggest that future eclipses, or close apparent approaches, should occur in the first decade of the 21st century.