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[en] An extensive set of high-speed photometric observations obtained with the Whole Earth Telescope network is used to show that the complex light curve of the ZZ Zeti (DAV) star G29-38 is dominated by a single, constant amplitude period of 615 s during the time span of these observations. The pulse arrival times for this period exhibit a systematic variation in phase readily explained by light-travel time effects produced by reflex orbital motion about an unseen companion. The best-fit model to the observations indicates a highly eccentric orbit, a period of 109 + or - 13 days and a minimum mass of 0.5 solar mass for the companion. 23 refs

[en] The visual red-dwarf pair is found to have a period of 18.3 y and a combined mass of 0.43 solar masses. Flares of the primary star are likely, though probably not over 0.5 mag. During the latest observations it was quiescent

[en] We report a discovery of the circularly polarized CH A ²Δ-X ²Π and B ²Σ^--X ²Π molecular bands in the spectrum of the DQ white dwarf (WD) GJ 841B. This is only the second such object since the discovery of G99-37 in the 1970s. GJ 841B is also the first WD to unambiguously show polarization in the C₂ Swan bands. By modeling the intensity and circular polarization in the CH bands, we determine the longitudinal magnetic field strength of 1.3 ± 0.5 MG and the temperature of 6100 ± 200 K in the absorbing region. We also present new observations of G99-37 and obtain estimates of the magnetic field strength 7.3 ± 0.3 MG and temperature 6200 ± 200 K, in good agreement with previous results.

[en] Theory of star evolution is presented in popular form. Hypotheses of star birth, their development and death in the form of white dwarf, neutron star or black hole are considered

[en] A two-stage mechanism is proposed whereby detached dwarf systems like V471 Tau may evolve into cataclysmic binaries. The two stages are (1) angular momentum loss from the secondary due to braking by a stellar wind linked with magnetic fields, and (2) angular momentum gain by the secondary from the orbital motion, due to tidal friction. This combination may be able to remove angular momentum from short-period binaries on a timescale of approximately 10⁹yr. (Auth.)

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