A high-eccentricity low-mass companion to HD 89744

HD 89744 is an F7 V star with a mass of 1.4 M., an effective temperature of 6166 K, an age of 2.0 Gyr, and metallicity [Fe/H] = 0.18. The radial veloc ity of the star has been monitored with the Advanced Fiber-Optic Echelle sp ectrograph at the Whipple Observatory since 1996, and evidence has been fou nd for a low-mass companion. The data were complemented by additional data from the Hamilton spectrograph at Lick Observatory during the companion's p eriastron passage in the fall of 1999. As a result, we have determined the star's orbital wobble to have a period P = 256 days, an orbital amplitude K = 257 m s(-1), and an eccentricity e = 0.7. From the stellar mass, we infe r that the companion has a minimum mass m(2) sin i = 7.2 M-J in an orbit wi th a semimajor axis a(2) = 0.88 AU. The eccentricity of the orbit, among th e highest known for extrasolar planets, continues the trend that extrasolar planets with semimajor axes greater than about 0.15 AU tend to have much h igher eccentricities than are found in our solar system. The high metallici ty of the parent star reinforces the trend that parent stars of extrasolar planets tend to have high metallicity.