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The bright F8 V star u Andromedae was previously reported to have a 4.6 day Doppler velocity periodicity, consistent with having a Jupiter-mass companion orbiting at 0.059 AU. Follow-up observations by both the Lick and Advanced Fiber-Optic Echelle spectrometer (AFOE) planet survey programs confirm this periodicity and reveal additional periodicities at 241 and 1267 days. These periodicities are consistent with Keplerian orbital motion and imply two additional companions orbiting at 0.83 and 2.5 AU, with minimum (M sin i) masses of 2.0 and 4.6 MJUP, respectively. Non-Keplerian explanations for the observed Doppler velocity variations, including radial and nonradial pulsations, rotational modulation of surface features, and stellar magnetic cycles, are examined. These explanations seem unlikely based on the observed photometric and chromospheric stability of the star. This putative three-planet system is found to be dynamically stable by both analytic techniques and numerical simulations. The outer two companions both reside in eccentric orbits, as do all nine known extrasolar planet candidates in distant orbits. If real, this multiple-planet system is the first around a main-sequence star, and its study should offer insights into planet formation, planet-planet interactions, and the observed eccentricities of planetary orbits.

The subgiant ? Boo (G5 IV) has been reported to show p-mode pulsations, as evidenced by variations in the equivalent width of its hydrogen Balmer lines (reported by Kjeldsen et al.). In an attempt to confirm this report, we observed ? Boo's radial velocity with the AFOE spectrograph for a total of 22 hours spread over seven successive nights in 1995 March. We find no evidence for the presence of excess power at the frequencies reported by Kjeldsen et al.; our upper limit corresponds to typical mode amplitudes of 0.5 m s-1, about 3 times smaller than the velocity amplitudes they inferred. Signals with amplitudes larger than 0.5 m s-1may be present at other frequencies within the 0-1000 ?Hz range, but evidence for such signals is scanty, and typical mode amplitudes greater than 1.5 m s-1are clearly inconsistent with our observations.