The detected velocity variations were too small to be cause by a body orbiting star A, which is more massive (see HR 5544 on page 919).
Not exact matches
Due to the close binary orbital interactions of the host star with Alpha Centauri A and Star B's own increased stellar activity during recent years, the astronomers were only able to
detect the radial -
velocity variations of host star B that were caused by the 3.236 - day orbit of the planet (with a semi-major axis of 0.04 AU) only after more than four and a half years of careful observation.
However, no significant
velocity variations were
detected in subsequent studies (Pettersen and Griffin, 1980; Marcy and Benitz, 1989; and Henry and McCarthy, 1990, last page).
On March 25, 2015, a team of astronomers using the Hubble Space Telescope revealed observations which indicate via the transit method that Alpha Centauri B may have a second planet «c» in a hot inner orbit, just outside planet candidate «b.» After observing Alpha Centauri B in 2013 and 2014 for a total of 40 hours, the team failed to
detect any transits involving planet b (previously
detected using the radial
velocity variations method and recently determined not to be observed edge - on in a transit orbit around Star B).
Due to the close binary orbital interactions of the host star with Alpha Centauri A and Star B's own increased stellar activity during recent years, the astronomers were only able to
detect the radial -
velocity variations of host star B that were caused by the 3.236 - day orbit of the planet (with a semi-major axis of 0.04 AU) only after more than three years of careful observation.
No Jupiter - class planets within 3 AUs were
detected dusing radial -
velocity variations by 2006 (Wittenmyer et al, 2006, page 186, Table 5; (Cumming et al, 1999; Abt and Levy, 1976, page 286, Table 2 for HR 799).
Prior to 2009, small but significant
variations in radial
velocity had been
detected which may have been caused by a substellar companion of one to nine Jupiter - masses with an orbital period of 50 years of less (Campbell et al, 1988, pages 904, 906, and 919).
The transit signals were
detected in photometric data from the Kepler satellite, and were confirmed to arise from planets using a combination of large transit - timing
variations, radial -
velocity variations, Warm - Spitzer observations, and statistical analysis of false - positive probabilities.
As a subgiant star subject to pulsations which affect careful measurements of
variations in radial
velocity caused by the gravitational pull of substellar companions, astronomers would find it very difficult to
detect any Earth - type planet around Beta Hydri using present methods.
As CORVAL monitoring failed to
detect significant radial
velocity variations over period of 3,400 days — or over 9.3 years (Duquennoy and Mayor, 1991, pp. 492 and 506), the detection is now considered to be spurious.
An attempt to find large planets from December 1986 to February 1987 failed to
detect large periodic
variations in radial
velocities (McMillan and Smith, 1987; more discussion at Hatzes et al, 2004).
Radial
velocity variations have been
detected (Andrei A. Tokovinin, 1992).
However, no changes in radial
velocity were
detected between 1974 and 1984 to confirm possible
variations found around 1920 (R. F. Griffin, 1984; and Beardsley et al, 1974).