GD 66 bとは 意味・読み方・使い方

GD 66 b is an unconfirmed extrasolar planet orbiting the DAV type pulsating white dwarf GD 66. Small variations in the phase of pulsation suggest that the star is moving in a small circle due to the gravitational pull of a smaller unseen body. This method is similar to that used to discover pulsar planets, except that the observations were in visible light instead of radio waves. The planet has not yet completed a full orbit during the time of observations and only one turning point of the observed-computed time curve has been observed, which makes it difficult to constrain the orbital parameters. The current best-fit circular orbit has a period of 5.69 years, with a planetary mass at least 2.36 times that of Jupiter (the measured quantity is the product of the true mass with the sine of the orbit's inclination angle). Observations made with the Spitzer Space Telescope failed to detect the planet, allowing an upper limit to be placed on its mass of 5–6 Jupiter masses.