Iota2 Normae

ι2 Normae, Latinised as Iota2 Normae, is a single,[9] blue-white star located in the southern constellation of Norma. It is positioned to the west of Rigil Kentaurus but can be difficult to spot against the Milky Way. It is faintly visible to the naked eye with an apparent visual magnitude of +5.57.[2] Measuring its parallax reveals it is located 280±10 light-years away from the sun.[1] At that distance, the visual magnitude is diminished by an interstellar extinction factor of 0.24 due to intervening dust.[10] The radial velocity of this star is zero, indicating it is neither moving toward nor away from the Sun.[4]

For other star systems with this Bayer designation, see ι Normae.
ι2 Normae
Location of ι2 Normae (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Norma
Right ascension  16h 09m 18.54876s[1]
Declination −57° 56′ 03.5420″[1]
Apparent magnitude (V) 5.57[2]
Characteristics
Spectral type B9.5 V[3]
B−V color index 0.04[2]
Astrometry
Radial velocity (Rv)0.00±0.37[4] km/s
Proper motion (μ) RA: −13.35±0.48[1] mas/yr
Dec.: −59.33±0.46[1] mas/yr
Parallax (π)11.65 ± 0.57[1] mas
Distance280 ± 10 ly
(86 ± 4 pc)
Absolute magnitude (MV)+0.91[5]
Details[6]
Mass2.59 M☉
Radius3.1[7] R☉
Luminosity40[8] L☉
Surface gravity (log g)4.34 cgs
Temperature10,593±360 K
Rotational velocity (v sin i)111 km/s
Age257 Myr
Other designations
ι2 Nor, CPD−57° 7613, FK5 3273, HD 144480, HIP 79153, HR 5994, SAO 243368
Database references
SIMBADdata

Iota2 Normae is a B-type main-sequence star with a stellar classification of B9.5 V.[3] It is larger than the Sun with 2.6[6] times the mass of the Sun and about 3.1[7] times the Sun's radius. The star is estimated to be 257 million years old and is spinning with a projected rotational velocity of 111 km/s. It is radiating approximately 40 times the Sun's luminosity from its photosphere at an effective temperature of 10,593 Kelvin.[6]

References
  1. van Leeuwen, F. (2007). "Validation of the New Hipparcos Reduction". Astronomy and Astrophysics. 474 (2): 653–64. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357.
  2. Lake, R. (1965). "Photometric Magnitudes and Colours for Bright Southern Stars (Sixth List)". Monthly Notes of the Astronomical Society of Southern Africa. 24: 41. Bibcode:1965MNSSA..24...41L.
  3. Houk, N.; Cowley, A. P. (1975). "University of Michigan Catalogue of two-dimensional spectral types for the HD stars. Volume I. Declinations -90_ to -53_ƒ0". University of Michigan Catalogue of two-dimensional spectral types for the HD stars. Volume I. Declinations -90_ to -53_ƒ0. Bibcode:1975mcts.book.....H.
  4. Kharchenko, N. V.; Scholz, R.-D.; Piskunov, A. E.; Röser, S.; Schilbach, E. (2007). "Astrophysical supplements to the ASCC-2.5: Ia. Radial velocities of ˜55000 stars and mean radial velocities of 516 Galactic open clusters and associations". Astronomische Nachrichten. 328 (9): 889. arXiv:0705.0878. Bibcode:2007AN....328..889K. doi:10.1002/asna.200710776.
  5. 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.
  6. David, Trevor J.; Hillenbrand, Lynne A. (2015). "The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets". The Astrophysical Journal. 804 (2): 146. arXiv:1501.03154. Bibcode:2015ApJ...804..146D. doi:10.1088/0004-637X/804/2/146.
  7. Pasinetti Fracassini, L. E.; et al. (February 2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS)", Astronomy and Astrophysics (Third ed.), 367: 521–524, arXiv:astro-ph/0012289, Bibcode:2001A&A...367..521P, doi:10.1051/0004-6361:20000451.
  8. McDonald, I.; Zijlstra, A. A.; Boyer, M. L. (2012). "Fundamental parameters and infrared excesses of Hipparcos stars". Monthly Notices of the Royal Astronomical Society. 427: 343. arXiv:1208.2037. Bibcode:2012MNRAS.427..343M. doi:10.1111/j.1365-2966.2012.21873.x.
  9. Chini, R.; et al. (2012), "A spectroscopic survey on the multiplicity of high-mass stars", Monthly Notices of the Royal Astronomical Society, 424 (3): 1925, arXiv:1205.5238, Bibcode:2012MNRAS.424.1925C, doi:10.1111/j.1365-2966.2012.21317.x.
  10. Gontcharov, G. A. (November 2012), "Spatial distribution and kinematics of OB stars", Astronomy Letters, 38 (11): 694–706, arXiv:1606.09028, Bibcode:2012AstL...38..694G, doi:10.1134/S1063773712110035.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.