An extremely low mass companion to the solar-type star 70 Virginis is inferred from the observed periodic Doppler reflex motion of the primary during 8 yr. The minimum mass (M_2 sin i) of 70 Vir "B" is 6.6 Jovian masses (M_J), which falls in the mass range associated with "extrasolar giant planets" (0.3-15 M_J). An orbital fit to the velocities yields a period P = 116.6 days, an amplitude K = 318 m s~(-1), and an eccentricity e = 0.40. The residuals to the fit scatter by 8 m s~(-1), consistent with the errors. Thus 70 Vir B and 51 Peg B represent the first planets found outside our solar system. Alternatively, the probability that 70 Vir B is an orbiting brown dwarf of mass M > 40 M_J is ～1%, requiring an extreme (face-on) orbital inclination of i < 9°. With a likely mass of 6.6-9 M_J, 70 Vir B lies in the nebulously defined domain between solar system planets and brown dwarfs. Its effective temperature is computed to be ～90℃. The formation of such giant planets in eccentric orbits is not explained by current theory.
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机译：从8年期间观察到的初生儿童的周期性多普勒反射运动可以推断出，太阳型恒星70 Virginis的质量极低。 70 Vir“ B”的最小质量（M_2 sin i）为6.6木星质量（M_J），该质量属于与“太阳系超大行星”（0.3-15 M_J）相关的质量范围。与速度的轨道拟合得出周期P = 116.6天，振幅K = 318 m s〜（-1），偏心率e = 0.40。拟合的残差分散了8 m s〜（-1），与误差一致。因此，70 Vir B和51 Peg B代表了太阳系外发现的第一批行星。另外，70 Vir B是质量大于等于40 M_J的轨道棕矮星的概率约为1％，需要极大的（正面）轨道倾角i <9°。 70 Vir B的质量可能为6.6-9 M_J，位于太阳系行星和褐矮星之间的模糊范围内。计算出的有效温度为〜90℃。当前理论没有解释偏心轨道上这种巨型行星的形成。
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