A group of astronomers at the Universidad de Santiago de Compostela (USC) has discovered a huge planet in the star system Gliese 22, Spain's EFE news agency reported Wednesday. The finding has been reported in the Astronomy and Astrophysics magazine. Read more
Title: Visual orbit for the low-mass binary Gliese 22 AC from speckle interferometry Authors: J. Woitas, V.S. Tamazian, J.A. Docobo, Ch. Leinert
Based on 14 data points obtained with near-infrared speckle interferometry and covering an almost entire revolution, we present a first visual orbit for the low-mass binary system Gliese 22 AC. The quality of the orbit is largely improved with respect to previous astrometric solutions. The dynamical system mass is 0.592 +- 0.065 solar masses, where the largest part of the error is due to the Hipparcos parallax. A comparison of this dynamical mass with mass-luminosity relations on the lower main sequence and theoretical evolutionary models for low-mass objects shows that both probably underestimate the masses of M dwarfs. A mass estimate for the companion Gliese 22 C indicates that this object is a very low-mass star with a mass close to the hydrogen burning mass limit.