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Artistic rendering of HD 13189 b |
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| Observation data Epoch J2000.0 Equinox J2000.0 |
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|---|---|
| Constellation | Triangulum |
| Right ascension | 02h 09m 40.17260s[1] |
| Declination | +32° 18′ 59.1649″[1] |
| Apparent magnitude (V) | +7.57[2] |
| Characteristics | |
| Spectral type | K1II-III[3] |
| Astrometry | |
| Radial velocity (Rv) | 25.39[4] km/s |
| Proper motion (μ) | RA: 2.62[1] mas/yr Dec.: 5.32[1] mas/yr |
| Parallax (π) | 1.78 ± 0.73[1] mas |
| Distance | approx. 1800 ly (approx. 600 pc) |
| Absolute magnitude (MV) | –3.8[5] |
| Details | |
| Mass | 2–7[2] M☉ |
| Radius | 45.5[6] to 50.4[7] R☉ |
| Surface gravity (log g) | 1.74[7] |
| Luminosity | 3,980[5] L☉ |
| Temperature | 4,365[6] K |
| Metallicity [Fe/H] | -0.58 ± 0.04[8] dex |
| Other designations | |
Coordinates: 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.[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. This mass range is typical of a B-type main sequence star,[10] suggesting the star belong to stellar class B when it was on the main sequence. 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]
| Extrasolar planet | List of extrasolar planets | |
|---|---|---|
| Orbital elements | ||
| Semimajor axis | (a) | 1.85 ± 0.35 AU |
| Eccentricity | (e) | 0.28 ± 0.06 |
| Orbital period | (P) | 471.6 ± 6 d |
| Argument of periastron |
(ω) | 160.7 ± 12° |
| Time of periastron | (T0) | 2452327.9 ± 20.2 JD |
| Semi-amplitude | (K) | 6.8 ± 1.5 m/s |
| Physical characteristics | ||
| Mass | (m) | >14 ± 6 MJ |
| Discovery information | ||
| Discovery date | 2005 | |
| Discoverer(s) | Hatzes et al. | |
| Detection method | Radial Velocity | |
| Discovery site | Texas, United States | |
| Discovery status | Published | |
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 Texas in 2005.