Nu Pavonis

Nu Pavonis
Location of 𝜈 Pavonis (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Pavo
Right ascension 18h 31m 22.42509s[1]
Declination −62° 16′ 41.8853″[1]
Apparent magnitude (V) 4.64 (4.60 - 4.64[2])
Characteristics
Evolutionary stage main sequence[3]
Spectral type B7III[4]
U−B color index −0.39[5]
B−V color index −0.11[5]
Variable type SPB[2]
Astrometry
Radial velocity (Rv)+16.95[6] km/s
Proper motion (ÎŒ) RA: âˆ’1.11[1] mas/yr
Dec.: âˆ’45.31[1] mas/yr
Parallax (π)7.43 Â± 0.24 mas[1]
Distance440 ± 10 ly
(135 ± 4 pc)
Absolute magnitude (MV)-1.01[4]
Orbit[7]
Period (P)1.711529±0.000005 d
Eccentricity (e)0.0
Periastron epoch (T)2,450,276.5502±0.0007 HJD
Argument of periastron (ω)
(secondary)
127±12°
Semi-amplitude (K1)
(primary)
43.8±0.1 km/s
Details
Mass4.39[8] M
Luminosity659[8] L
Temperature12,764[8] K
Rotational velocity (v sin i)125.0[9] km/s
Other designations
Îœ Pav, CD−62°1213, GC 25227, HD 169978, HIP 90797, HR 6916, SAO 254273, WDS J18314-6217AB[10]
Database references
SIMBADdata

Nu Pavonis is a possible triple star system[11] in the southern constellation of Pavo. It is visible to the naked eye as a faint star that varies in apparent visual magnitude from 4.60 to 4.64 over a period of 0.85584 days.[2] The system lies approximately 440 light years from the Sun based on parallax,[1] and is drifting further away with a radial velocity of +17 km/s.[6] It is a possible member of the Wolf 630 group of co-moving stars.[3]

A light curve for Nu Pavonis, plotted from TESS data[12]

This is a single-lined spectroscopic binary system with an orbital period of just 1.71 days in a circular orbit.[7] The unresolved[3] components are close enough that their tidal interaction is significant.[7] The visible component is a slowly pulsating B-type star with a stellar classification of B7III.[4] This implies it is an evolved giant star, but it is actually more likely to be on the main sequence. An X-ray emission has been detected from the pair.[3]

The third component is a visible companion, probably a pre-main-sequence star, at magnitude 13.7 and separation 3.1″. This star is estimated at 0.15 solar masses and an effective temperature of 3,192 K.[8] It too is an X-ray source.[3]

  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 Cite error: The named reference AAVSO was invoked but never defined (see the help page).
  3. ^ a b c d e Cite error: The named reference Huélamo2003 was invoked but never defined (see the help page).
  4. ^ a b c Cite error: The named reference XHIP was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference Ducati2002 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference Pourbaiz2004 was invoked but never defined (see the help page).
  7. ^ a b c Cite error: The named reference DeCat2000 was invoked but never defined (see the help page).
  8. ^ a b c d Cite error: The named reference Hubrig was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference Glebocki2005 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference MAST was invoked but never defined (see the help page).