HD 27894

Last updated
HD 27894
Observation data
Epoch J2000.0       Equinox J2000.0
Constellation Reticulum
Right ascension 04h 20m 47.046106s [1]
Declination −59° 24 39.024641 [1]
Apparent magnitude  (V)9.42
Characteristics
Spectral type K2 V [2]
U−B color index +0.90 [3]
B−V color index +1.005 [3]
Astrometry
Radial velocity (Rv)82.74±0.15 [1]  km/s
Proper motion (μ)RA: 182.473±0.012  mas/yr [1]
Dec.: 270.012±0.017  mas/yr [1]
Parallax (π)22.8888 ± 0.0121  mas [1]
Distance 142.50 ± 0.08  ly
(43.69 ± 0.02  pc)
Details
Mass 0.86 ± 0.06 [4]   M
Surface gravity (log g)4.54 ± 0.05 [4]   cgs
Temperature 4920 ± 45 [4]   K
Metallicity [Fe/H]+0.20 [5]   dex
Age 7.7 ± 2.3 [4]   Gyr
Other designations
CD−59° 829, HD  27894, HIP  20277, LTT  1953. [3]
Database references
SIMBAD data

HD 27894 is a 9th magnitude star located approximately 143 light years away in the constellation of Reticulum. It is an orange dwarf (spectral type K2V), a type dimmer and cooler than the Sun.

Contents

In 2005, the Geneva Extrasolar Planet Search Team announced the discovery of an extrasolar planet orbiting the star. [6] In 2017, the discovery of two additional exoplanets was announced. One is very close to the star like the one discovered earlier, while the other one orbits the star at a much larger distance. It is the first system where such a large gap between orbital distances has been found. [7] [8] In 2022, the inclination and true mass of HD 27894 d were measured via astrometry. The study only found strong evidence for planets b and d. [9]

The HD 27894 planetary system [7] [9]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b ≥0.665+0.009
−0.007
  MJ
0.125±0.000118.02+0.01
−0.02
0.047+0.012
−0.008
c ≥0.162+0.011
−0.040
  MJ
0.198±0.00136.07+0.26
−0.09
0.015+0.020
−0.002
d 6.493+0.987
−0.353
  MJ
5.362+0.206
−0.223
5019.5+32.6
−31.1
0.343+0.031
−0.026
101.524+14.742
−31.503
°

See also

Related Research Articles

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References

  1. 1 2 3 4 5 6 Vallenari, A.; et al. (Gaia Collaboration) (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics . arXiv: 2208.00211 . doi: 10.1051/0004-6361/202243940 . Gaia DR3 record for this source at VizieR.
  2. Houk, Nancy (1979). Michigan catalogue of two-dimensional spectral types for the HD stars. Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan. Bibcode:1978mcts.book.....H. LCCN   78010745.
  3. 1 2 3 "LTT 1953 -- High proper-motion Star", SIMBAD Astronomical Database, Centre de Données astronomiques de Strasbourg , retrieved 2012-02-05
  4. 1 2 3 4 Trevisan, M.; et al. (November 2011), "Analysis of old very metal rich stars in the solar neighbourhood", Astronomy & Astrophysics, 535: A42, arXiv: 1109.6304 , Bibcode:2011A&A...535A..42T, doi:10.1051/0004-6361/201016056, S2CID   49565866 . See table 13.
  5. Sousa, S. G.; et al. (August 2008), "Spectroscopic parameters for 451 stars in the HARPS GTO planet search program. Stellar [Fe/H] and the frequency of exo-Neptunes", Astronomy and Astrophysics, 487 (1): 373–381, arXiv: 0805.4826 , Bibcode:2008A&A...487..373S, doi:10.1051/0004-6361:200809698, S2CID   18173201
  6. Moutou, C.; et al. (2005). "The HARPS search for southern extra-solar planets IV. Three close-in planets around HD 2638, HD 27894 and HD 63454". Astronomy and Astrophysics. 439 (1): 367–373. Bibcode:2005A&A...439..367M. doi: 10.1051/0004-6361:20052826 .
  7. 1 2 Trifonov, T.; Kürster, M.; Zechmeister, M.; Zakhozhay, O. V.; Reffert, S.; Lee, M. H.; Rodler, F.; Vogt, S. S.; Brems, S. S. (2017). "Three planets around HD 27894. A close-in pair with a 2:1 period ratio and an eccentric Jovian planet at 5.4 AU". Astronomy & Astrophysics. 602: L8. arXiv: 1706.00509 . Bibcode:2017A&A...602L...8T. doi:10.1051/0004-6361/201731044. S2CID   119105619.
  8. Tomasz Nowakowski (June 12, 2017). "Two new massive planets detected around the star HD 27894" . Retrieved June 12, 2017.
  9. 1 2 Feng, Fabo; Butler, R. Paul; et al. (August 2022). "3D Selection of 167 Substellar Companions to Nearby Stars". The Astrophysical Journal Supplement Series . 262 (21): 21. arXiv: 2208.12720 . Bibcode:2022ApJS..262...21F. doi:10.3847/1538-4365/ac7e57. S2CID   251864022.