HD 190984 b

Extrasolar planet in the constellation Pavo

HD 190984 b (also known as HIP 99496 b) is an exoplanet which orbits the F-type main sequence star HD 190984, located approximately 486 light-years away in the constellation Pavo. This planet has a minimum mass three times that of Jupiter and takes 13 years and four-and-a-half months to orbit the star at a semimajor axis of 5.5 AU with an eccentricity of 0.57.^[1] This planet was detected by HARPS on October 19, 2009, together with 29 other planets.

Since this is a very long-period planet detected by the radial velocity method and this planet didn't complete its orbit during the continuous observations, the error range for orbital period is very large, at 4885 ± 1600 days or 13.37 ± 4.4 years. This puts it in the range of semimajor axes between 4.2 and 6.6 AU. So this planet will need more years of observations to better constrain the period and semimajor axis.

In 2023, the inclination and true mass of HD 190984 b were determined via astrometry, and its orbit was updated, finding a longer period and larger semi-major axis than previously estimated, although still with a large margin of error.^[2]

References

^ ^a ^b ^c Santos, Nuno C.; Mayor, Michel; Benz, Willy; Bouchy, François; et al. (2010). "The HARPS Search for Southern Extra-solar Planets XXI. Three New Giant Planets Orbiting the Metal-poor Stars HD 5388, HD 181720, and HD 190984". Astronomy and Astrophysics. 512 (A47): A47. arXiv:0912.3216. Bibcode:2010A&A...512A..47S. doi:10.1051/0004-6361/200913489. S2CID 118675798.
^ ^a ^b ^c Xiao, Guang-Yao; Liu, Yu-Juan; et al. (May 2023). "The Masses of a Sample of Radial-Velocity Exoplanets with Astrometric Measurements". Research in Astronomy and Astrophysics. 23 (5): 055022. arXiv:2303.12409. Bibcode:2023RAA....23e5022X. doi:10.1088/1674-4527/accb7e.

Constellation of Pavo

Stars

Bayer	α (Peacock) β γ δ ε ζ η θ ι κ λ μ¹ μ² ν ξ ο π ρ σ τ υ φ¹ φ² ω
Variable	R V X Y SX AR BD KZ MW NU NZ V346 V347
HR	6586 6624 6634 6740 6760 6796 6805 6808 6828 6899 6908 6939 6996 7004 7012 7015 7022 7027 7111 7130 7161 7221 7278 7320 7383 7434 7435 7455 7498 7513 7527 7531 7558 7579 7587 7588 7644 7663 7691 7707 7732 7838 7872 7959 8019 8061 8073 8081 8125 8159
HD	161475 162521 164427 175007 175167 176522 179419 181433 186302 190984 192887 195190 195772 196050
Other	Gliese 693 SCR 1845−6357 SCR 1826−6542