HD 13189

HD 13189
HD 13189 1AU Celestia.jpg
HD 13189 as seen in Celestia.
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Triangulum
Right ascension  02h 09m 40.1721s[1]
Declination +32° 18′ 59.1607″[1]
Apparent magnitude (V) +7.57[2]
Spectral type K1II-III[3]
Radial velocity (Rv)25.39[4] km/s
Proper motion (μ) RA: 2.465±0.085[1] mas/yr
Dec.: 4.934±0.089[1] mas/yr
Parallax (π)1.9813 ± 0.0621[1] mas
Distance1,650 ± 50 ly
(500 ± 20 pc)
Absolute magnitude (MV)–3.8[5]
Mass2–7[2] M
Radius45.5[6] to 50.4[7] R
Luminosity3,980[5] L
Surface gravity (log g)1.74[7] cgs
Temperature4,365[6] K
Metallicity [Fe/H]-0.58 ± 0.04[8] dex
Other designations
BD+31° 370, HIP 10085, SAO 55309.[9]
Database references

Coordinates: Sky map 02h 09m 40.1717s, +32° 18′ 59.1690″

HD 13189 is an 8th magnitude star in Triangulum constellation.

In 2005, a planetary companion or brown dwarf was announced in orbit around this star. At the time, the parallax estimate was 0.54 ± 0.93 mas, which would suggest a distance of 6,040 ly (1,850 pc) with a high margin of error.[2] In 2007, van Leeuwen published a revised parallax measurement of 1.78 ± 0.73, which corresponds to a distance of 1,830 ly (560 pc) with a smaller but still significant margin of error.[10] In 2018 the Gaia spacecraft measured a parallax of 1.9813±0.0621 which is a distance of 1,650 ly (510 pc) with an error of only 50 ly (15 pc).[1]

It has a spectral classification of K1II-III, making it a giant star that has evolved away from the main sequence. The mass is 2–7 times the Sun,[2] while measurements of the star's radius give estimates of 45.5[6] or 50.4[7] solar radii. The atmosphere of the star displays short period radial velocity variations with a primary period of 4.89 days. This behavior is typical for giant K-type stars such as this and it is not the result of a close-orbit planetary companion.[5]

The star is possibly the most massive of all planet-harboring stars.[11]

HD 13189 b[]

HD 13189 b
Discovered byHatzes et al.
Discovery siteTautenburg, Germany
Discovery date2005
Radial Velocity
Orbital characteristics
1.85 ± 0.35 AU (277,000,000 ± 52,000,000 km)
Eccentricity0.28 ± 0.06
471.6 ± 6 d
2452327.9 ± 20.2
160.7 ± 12
Semi-amplitude6.8 ± 1.5
Physical characteristics
Mass>14 ± 6 MJ

HD 13189 b is an exoplanet or brown dwarf with mass ranges from 8 to 20 Jupiter mass. This object is located at a mean distance of 277 Gm (1.85 AU) from the star, taking 472 days to make one elliptical orbit.

This object was discovered in Tautenburg, Germany in 2005.[12]


  1. ^ a b c d e f Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
  2. ^ a b c d Hatzes, A. P.; et al. (2005). "A giant planet around the massive giant star HD 13189". Astronomy and Astrophysics. 437 (2): 743–751. Bibcode:2005A&A...437..743H. doi:10.1051/0004-6361:20052850.
  3. ^ Lee, B.-C.; et al. (May 2011). "A likely exoplanet orbiting the oscillating K-giant α Arietis". Astronomy & Astrophysics. 529: A134. arXiv:1104.4431. Bibcode:2011A&A...529A.134L. doi:10.1051/0004-6361/201016293.
  4. ^ Famaey, B.; et al. (January 2005). "Local kinematics of K and M giants from CORAVEL/Hipparcos/Tycho-2 data. Revisiting the concept of superclusters". Astronomy and Astrophysics. 430 (1): 165–186. arXiv:astro-ph/0409579. Bibcode:2005A&A...430..165F. doi:10.1051/0004-6361:20041272.
  5. ^ a b c Hatzes, Artie P.; Zechmeister, Mathias (October 2008). "Stellar oscillations in planet-hosting giant stars". Journal of Physics: Conference Series. 118 (1): 012016. Bibcode:2008JPhCS.118a2016H. doi:10.1088/1742-6596/118/1/012016.
  6. ^ a b c van Belle, Gerard T.; von Braun, Kaspar (April 2009). "Directly Determined Linear Radii and Effective Temperatures of Exoplanet Host Stars". The Astrophysical Journal. 694 (2): 1085–1098. arXiv:0901.1206. Bibcode:2009ApJ...694.1085V. doi:10.1088/0004-637X/694/2/1085. See Table 3 of the online data.
  7. ^ a b c Baines, Ellyn K.; et al. (June 2008). "CHARA Array Measurements of the Angular Diameters of Exoplanet Host Stars". The Astrophysical Journal. 680 (1): 728–733. arXiv:0803.1411. Bibcode:2008ApJ...680..728B. doi:10.1086/588009.
  8. ^ Kim, J. H.; et al. (December 2005). "High-Resolution Spectroscopy of the Planetary Host HD 13189: Highly-Evolved and Metal-Poor". Bulletin of the American Astronomical Society. 37 (1): 1269. Bibcode:2006PhuZ...37....4.. doi:10.1002/piuz.200690006. Archived from the original on 2007-03-29.
  9. ^ "HD 13189 -- Star". SIMBAD. Retrieved 2011-12-13.
  10. ^ van Leeuwen, F. (November 2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357.
  11. ^ "Notes for planet HD 13189 b". The Extrasolar Planets Encyclopaedia. Retrieved 2015-09-15.
  12. ^ A Giant Planet Around The Massive Giant Star HD 13189 Archived 2015-07-20 at the Wayback Machine

External links[]