Theta Normae

Theta Normae
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Norma
Right ascension 16h 15m 15.31794s[1]
Declination −47° 22′ 19.2710″[1]
Apparent magnitude (V) 5.13[2]
Characteristics
Spectral type B8 V[3]
B−V color index −0.12[2]
Astrometry
Radial velocity (Rv)+1.4±4.2[4] km/s
Proper motion (μ) RA: −34.771 mas/yr
Dec.: −45.813 mas/yr
Parallax (π)9.2718 ± 0.1692 mas[5]
Distance352 ± 6 ly
(108 ± 2 pc)
Absolute magnitude (MV)−0.23[6]
Details
Mass3.6[7] M☉
Radius3.05[8] R☉
Luminosity184[9] L☉
Surface gravity (log g)4.5[7] cgs
Temperature12,341[9] K
Rotational velocity (v sin i)251[10] km/s
Age17[7] Myr
Other designations
θ Nor, CPD−47° 10611, HD 145842, HIP 79653, HR 6045, SAO 226600[11]
Database references
SIMBADdata

θ Normae, Latinised as Theta Normae, is a binary star system in the constellation Norma. It has an apparent visual magnitude of 5.13[2] and is visible to the naked eye as a faint, blue-white-hued point of light. Based upon an annual parallax shift of 9.27 mas as seen from Earth,[5] this system is located about 352 light-years from the Sun. At that distance, the visual magnitude of these stars is diminished by an extinction of 0.45 due to interstellar dust.[12]

Chini et al. (2012) identified this as a single-lined spectroscopic binary system.[13] The visible component is a B-type main-sequence star with a stellar classification of B8 V.[3] It is about 17[7] million tears old and is spinning rapidly with a projected rotational velocity of 251 km/s.[10] The star has 3.6[7] times the mass of the Sun and 3.05[8] times the Sun's radius. It is radiating about 184 times the Sun's luminosity from its photosphere at an effective temperature of 12,341 K.[9] This system displays an infrared excess, suggesting a debris disk is orbiting at a mean radius of 21.8 AU with a temperature of 220 K.[8]

  1. ^ a b Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  2. ^ a b c Cite error: The named reference Corben1968 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference houk1978 was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference deBruijne2012 was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference vanLeeuwen2007 was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  7. ^ a b c d e Cite error: The named reference gullikson2016 was invoked but never defined (see the help page).
  8. ^ a b c Cite error: The named reference Cotten2016 was invoked but never defined (see the help page).
  9. ^ a b c Cite error: The named reference Mcdonald2012 was invoked but never defined (see the help page).
  10. ^ a b Cite error: The named reference uesugi_fukuda70 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference Gontcharov2012 was invoked but never defined (see the help page).
  13. ^ Cite error: The named reference chini2012 was invoked but never defined (see the help page).