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Full-Text Articles in Physical Sciences and Mathematics
A Planet At 5 Au Around 55 Cancri, Geoffrey W. Marcy, R. Paul Butler, Debra A. Fischer, Greg Laughlin, Steve S. Vogt, Gregory W. Henry, Dimitri Pourbaix
A Planet At 5 Au Around 55 Cancri, Geoffrey W. Marcy, R. Paul Butler, Debra A. Fischer, Greg Laughlin, Steve S. Vogt, Gregory W. Henry, Dimitri Pourbaix
Information Systems and Engineering Management Research Publications
We report precise Doppler-shift measurements of 55 Cancri (G8 V) obtained from 1989 to 2002 at Lick Observatory. The velocities reveal evidence for an outer planetary companion to 55 Cancri orbiting at 5.5 AU. The velocities also confirm a second, inner planet at 0.11 AU. The outer planet is the first extrasolar planet found that orbits near or beyond the orbit of Jupiter. It was drawn from a sample of ~50 stars observed with sufficient duration and quality to detect a giant planet at 5 AU, implying that such planets are not rare. The properties of this Jupiter analog may …
A False Planet Around Hd 192263, Gregory W. Henry, Robert A. Donahue, Sallie L. Baliunas
A False Planet Around Hd 192263, Gregory W. Henry, Robert A. Donahue, Sallie L. Baliunas
Information Systems and Engineering Management Research Publications
We present new high-precision Strömgren photometry and Ca II H and K spectrophotometry of HD 192263. Based on radial velocity variations detected previously by two groups, this K2 V star was thought to host a 0.75 MJup (minimum mass) planetary companion in a 24 day orbit. Our photometric observations reveal periodic variations that match the purported planetary orbital period, while the Ca II H and K emission fluxes are modulated on half the planetary period. This suggests that rotational modulation of the visibility of stellar surface activity is the source of the observed radial velocity variations. Therefore, HD 192263 should …