Eta Normae

Eta Normae
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Norma
Right ascension 16h 03m 12.89783s[1]
Declination −49° 13′ 46.9151″[1]
Apparent magnitude (V) 4.65[2]
Characteristics
Evolutionary stage horizontal branch
Spectral type G8III[3]
U−B color index +0.64[2]
B−V color index +0.92[2]
Astrometry
Radial velocity (Rv)−0.3±2.8[4] km/s
Proper motion (μ) RA: 42.05[1] mas/yr
Dec.: 9.14[1] mas/yr
Parallax (π)14.86 ± 0.25 mas[1]
Distance219 ± 4 ly
(67 ± 1 pc)
Absolute magnitude (MV)0.524[5]
Details
Mass2.78[5] M☉
Radius11.07+0.23
−0.09[6] R☉
Luminosity71.9±3.1[6] L☉
Surface gravity (log g)2.84[5] cgs
Temperature5052+16
−51[6] K
Metallicity [Fe/H]−0.05[5] dex
Other designations
η Nor, CD−48° 10512, HD 143546, HIP 78639, HR 5962, SAO 226466[7]
Database references
SIMBADdata

Eta Normae, Latinized from η Normae, is a single[8] star in the southern constellation of Norma. It is visible to the naked eye as a faint, yellow-hued star with an apparent visual magnitude of 4.65.[2] The distance to this star is about 219 light years, based on parallax.[1] The Gamma Normids radiate from a position near this star.[9]

This is an aging giant star with a stellar classification of G8III,[3] having exhausted the supply of hydrogen at its core then swollen and cooled off the main sequence. At present it has a diameter of 11[6] times that of the Sun. It is a red clump[5] giant, meaning it is on the horizontal branch and is generating energy through core helium fusion. The star has 2.78[5] times the mass of the Sun and is radiating 72[6] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 5,052 K.[6] It is a source for X-ray emission.[10]

  1. ^ a b c d e f Cite error: The named reference vanLeeuwen2007 was invoked but never defined (see the help page).
  2. ^ a b c d Cite error: The named reference clpl4_99 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 c d e f Cite error: The named reference Liu2007 was invoked but never defined (see the help page).
  6. ^ a b c d e f Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  7. ^ "eta Nor". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2017-08-12.{{cite web}}: CS1 maint: postscript (link)
  8. ^ Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference Lunsford2009 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference Haakonsen2009 was invoked but never defined (see the help page).