HD 16955

In this article we will explore in depth the topic of HD 16955, its impact on today's society and its relevance in different areas. Throughout history, HD 16955 has been a topic of great interest and research, with multiple perspectives and approaches that have contributed to the understanding and development of new ideas. From its influence on the economy, culture and politics, to its impact on people's daily lives, HD 16955 has proven to be a multidimensional issue that deserves to be analyzed and discussed. Through exhaustive analysis, this article will seek to provide a clear and comprehensive view on HD 16955, offering readers a deeper and more meaningful understanding of its importance today.

HD 15524
Observation data
Epoch J2000      Equinox J2000
Constellation Aries
Right ascension 02h 43m 51.24421s[1]
Declination +25° 38′ 18.0493″[1]
Apparent magnitude (V) 6.376[2]
Characteristics
Spectral type A3 V[3]
B−V color index 0.089±0.002[4]
Astrometry
Radial velocity (Rv)−10.3±3.1[5] km/s
Proper motion (μ) RA: −4.98±0.70[1] mas/yr
Dec.: +6.04±0.52[1] mas/yr
Parallax (π)9.59±0.76 mas[1]
Distance340 ± 30 ly
(104 ± 8 pc)
Absolute magnitude (MV)+1.18±0.13[2]
Details
HD 16955 A
Mass2.25±0.08[6] M☉
Luminosity26.9+3.3
−2.9[2] L☉
Temperature8,450±164[2] K
Rotational velocity (v sin i)175[7] km/s
Other designations
BD+25° 441, HD 16955, HIP 12744, HR 803, SAO 75539[8]
Database references
SIMBADdata

HD 16955, also known as HR 803, is a double or multiple star. With an apparent visual magnitude of 6.376,[2] is lies at or below the nominal limit for visibility with a typical naked eye. The measured annual parallax shift is 9.59 milliarcseconds, which yields an estimated distance of around 340 light years. The star is moving closer to the Sun with a heliocentric radial velocity of around -10 km/s.[5]

This is an A-type main-sequence star with a stellar classification of A3 V.[3] Hauck et al. (1995) identified this as a Lambda Boötis star with a circumstellar shell,[9] but this now appears to be unlikely.[2] It has 2.25[6] times the mass of the Sun and is spinning rapidly with a projected rotational velocity of 175 km/s.[7] The star is radiating about 27[2] times the Sun's luminosity from its photosphere at an effective temperature of roughly 8,450 K.[2]

HD 16955 has a magnitude 10.36 companion, component B, which is located, as of 2015, at an angular separation of 3.0 arcseconds along a position angle of 19°.[10] This is the likely source for the detected X-ray emission with a luminosity of 262.5×1020 W coming from these coordinates, since A-type stars are not expected to emit X-rays.[11] Component C is a more distant magnitude 12.94 companion located at a separation of 51.10 arcseconds along a position angle of 92°, as of 2015.[10]

References

  1. ^ a b c d e 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 c d e f g h Murphy, Simon J.; Paunzen, Ernst (April 2017), "Gaia's view of the λ Boo star puzzle", Monthly Notices of the Royal Astronomical Society, 466 (1): 546−555, arXiv:1612.01528, Bibcode:2017MNRAS.466..546M, doi:10.1093/mnras/stw3141, S2CID 119328659
  3. ^ a b Cowley, A.; et al. (April 1969). "A study of the bright A stars. I. A catalogue of spectral classifications". Astronomical Journal. 74: 375–406. Bibcode:1969AJ.....74..375C. doi:10.1086/110819.
  4. ^ 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.
  5. ^ a b Gontcharov, G. A. (November 2006). "Pulkovo Compilation of Radial Velocities for 35495 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 Zorec, J.; Royer, F. (2012). "Rotational velocities of A-type stars. IV. Evolution of rotational velocities". Astronomy & Astrophysics. 537: A120. arXiv:1201.2052. Bibcode:2012A&A...537A.120Z. doi:10.1051/0004-6361/201117691. S2CID 55586789.
  7. ^ a b Royer, F.; et al. (February 2007). "Rotational velocities of A-type stars. III. Velocity distributions". Astronomy and Astrophysics. 463 (2): 671–682. arXiv:astro-ph/0610785. Bibcode:2007A&A...463..671R. doi:10.1051/0004-6361:20065224. S2CID 18475298.
  8. ^ "HD 16955". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-02-26.
  9. ^ Hauck, B.; et al. (March 1995), "Three other λ Bootis stars with a shell", Astronomy and Astrophysics Supplement, 109: 505−510, Bibcode:1995A&AS..109..505H
  10. ^ a b Mason, B. D.; et al. (2014), "The Washington Visual Double Star Catalog", The Astronomical Journal, 122 (6): 3466–3471, Bibcode:2001AJ....122.3466M, doi:10.1086/323920.
  11. ^ Schröder, C.; Schmitt, J. H. M. M. (November 2007), "X-ray emission from A-type stars", Astronomy and Astrophysics, 475 (2): 677−684, Bibcode:2007A&A...475..677S, doi:10.1051/0004-6361:20077429.