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HD 28375

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HD 28375
Location of HD 28375 (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Taurus
Right ascension 04h 28m 32.12178s[1]
Declination +01° 22′ 50.9687″[1]
Apparent magnitude (V) 5.53[2]
Characteristics
Spectral type B3V[3]
U−B color index -0.55[4]
B−V color index −0.099±0.008[2]
Astrometry
Radial velocity (Rv)18.0±4.3[5] km/s
Proper motion (μ) RA: +19.530[1] mas/yr
Dec.: −20.272[1] mas/yr
Parallax (π)6.8102 ± 0.1690 mas[1]
Distance480 ± 10 ly
(147 ± 4 pc)
Absolute magnitude (MV)0.19[2]
Details
Mass5.0±0.1[6] M
Luminosity126.75[2] L
Surface gravity (log g)4[3] cgs
Temperature13,000[3] K
Metallicity [Fe/H]0.05±0.06[7] dex
Rotational velocity (v sin i)13±3[8] km/s
Age3.1±2.1[6] Myr
Other designations
BD+01°757, FK5 1123, GC 5441, HD 28375, HIP 20884, HR 1415, SAO 111845[9]
Database references
SIMBADdata

HD 28375 is a single[10] star in the equatorial constellation of Taurus, near the southern constellation border with Eridanus. It was previously known by the Flamsteed designation 44 Eridani, although the name has fallen out of use because constellations were redrawn, placing the star out of Eridanus and into Taurus. The star is blue-white in hue and is dimly visible to the naked eye with an apparent visual magnitude of 5.53.[2] The distance to this star is approximately 480 light-years based on parallax.[1] It is drifting further away with a radial velocity of 18 km/s,[5] after having come to within an estimated 249 light-years some 3.7 million years ago.[2]

Cowley (1972) and later Bragança et al. (2012) found a stellar classification of B3V[11][12] for this object, matching a B-type main-sequence star. Houk and Swift assigned it a class of B5 III/IV,[13] suggesting it is a more evolved star that is entering the giant stage. It has five times the mass of the Sun and is around three million years old,[6] with a projected rotational velocity of just 13 km/s.[8] The star is radiating 127[2] times the luminosity of the Sun from its photosphere at an effective temperature of about 13,000 K.[3]

An infrared excess has been detected, indicating the presence of a circumstellar disk. The dust has a temperature of about 119 K and is orbiting 67 AU from the star.[3]

References

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  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 e f g Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015, S2CID 119257644.
  3. ^ a b c d e Liu, Qiong; Wang, Tinggui; Jiang, Peng (2014). "Bright Debris Disk Candidates Detected with Theakari/far-Infrared Surveyor". The Astronomical Journal. 148 (1): 3. arXiv:1308.5593. Bibcode:2014AJ....148....3L. doi:10.1088/0004-6256/148/1/3. S2CID 117353888.
  4. ^ Johnson, H. L. (1966). "UBVRIJKL Photometry of the Bright Stars". Communications of the Lunar and Planetary Laboratory. 4: 99. Bibcode:1966CoLPL...4...99J.
  5. ^ a b 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 c Tetzlaff, N.; et al. (January 2011), "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun", Monthly Notices of the Royal Astronomical Society, 410 (1): 190–200, arXiv:1007.4883, Bibcode:2011MNRAS.410..190T, doi:10.1111/j.1365-2966.2010.17434.x, S2CID 118629873
  7. ^ Gáspár, András; et al. (2016), "The Correlation between Metallicity and Debris Disk Mass", The Astrophysical Journal, 826 (2): 171, arXiv:1604.07403, Bibcode:2016ApJ...826..171G, doi:10.3847/0004-637X/826/2/171, S2CID 119241004.
  8. ^ a b Bragança, G. A.; Daflon, S.; Cunha, K.; Bensby, T.; Oey, M. S.; Walth, G. (2012). "Projected Rotational Velocities and Stellar Characterization of 350 B Stars in the Nearby Galactic Disk". The Astronomical Journal. 144 (5): 130. arXiv:1208.1674. Bibcode:2012AJ....144..130B. doi:10.1088/0004-6256/144/5/130. S2CID 118868235.
  9. ^ "HD 28375". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-12-18.
  10. ^ Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869–879, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
  11. ^ Cowley, A. (November 1972), "Spectral classification of the bright B8 stars", Astronomical Journal, 77: 750–755, Bibcode:1972AJ.....77..750C, doi:10.1086/111348.
  12. ^ Bragança, G. A.; et al. (November 2012), "Projected Rotational Velocities and Stellar Characterization of 350 B Stars in the Nearby Galactic Disk", The Astronomical Journal, 144 (5): 10, arXiv:1208.1674, Bibcode:2012AJ....144..130B, doi:10.1088/0004-6256/144/5/130, S2CID 118868235, 130.
  13. ^ Houk, N.; Swift, C. (1999), "Michigan catalogue of two-dimensional spectral types for the HD Stars", Michigan Spectral Survey, 5, Bibcode:1999MSS...C05....0H