HD 72561 is a star in the constellation Hydra. Its apparent magnitude is 5.867.[2] Based on parallax shift, it is located about 1,600 light-years (500 parsecs) away.[1]

HD 72561
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Hydra
Right ascension 08h 33m 43.47908s[1]
Declination +04° 45′ 25.1949″[1]
Apparent magnitude (V) 5.867[2]
Characteristics
Spectral type G5 III[3]
U−B color index +0.87[4]
B−V color index +1.07[4]
Astrometry
Radial velocity (Rv)+1.60 ± 0.3[5] km/s
Proper motion (μ) RA: −13.18[1] mas/yr
Dec.: −6.84[1] mas/yr
Parallax (π)1.98 ± 0.41 mas[1]
Distanceapprox. 1,600 ly
(approx. 500 pc)
Details[6][note 1]
Mass4.58 ± 0.40 M
Radius48.41 ± 9.26 R
Luminosity1109.6 ± 422.9 L
Surface gravity (log g)1.80 ± 0.15 cgs
Temperature4792 ± 36 K
Metallicity [Fe/H]−0.16 ± 0.10 dex
Age0.15 ± 0.04 Gyr
Other designations
BD+05° 1997, HIP 42008, HR 3378, SAO 116890[3]
Database references
SIMBADdata

HD 72561 is a G-type giant star. It is over 4 times as massive as the Sun and 48 times as wide. It is about 150 million years old.[6]

References edit

  1. ^ a b c d e f van Leeuwen, F. (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. S2CID 18759600.
  2. ^ a b Høg, E.; et al. (2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics. 355: L27–L30. Bibcode:2000A&A...355L..27H.
  3. ^ a b "HR 3378". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 23 August 2017.
  4. ^ a b Johnson, H. L. (1966). "UBVRIJKL Photometry of the Bright Stars". Communications of the Lunar and Planetary Laboratory. 4: 99. Bibcode:1966CoLPL...4...99J.
  5. ^ Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. S2CID 119231169.
  6. ^ a b Reffert, Sabine; Bergmann, Christoph; Quirrenbach, Andreas; Trifonov, Trifon; Künstler, Andreas (2015). "Precise radial velocities of giant stars". Astronomy & Astrophysics. 574: A116. arXiv:1412.4634. Bibcode:2015A&A...574A.116R. doi:10.1051/0004-6361/201322360. hdl:10722/215277. S2CID 59334290.

Notes edit

  1. ^ The Reffert et al. paper gives two different sets of results, depending on whether the star is a horizontal branch star or a red giant branch star. The parameters given here are for a horizontal branch star, since the probability of it being a horizontal branch star is 99%.