Phi1 Lupi

For other stars with this Bayer designation, see φ Lupi.
φ1 Lupi
Location of φ1 Lupi (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Lupus
Right ascension 15h 21m 48.36967s[1]
Declination −36° 15′ 40.9525″[1]
Apparent magnitude (V) 3.58[2]
Characteristics
Spectral type K5 III[3]
U−B color index +1.85[2]
B−V color index +1.534±0.005[4]
Astrometry
Radial velocity (Rv)−29.4±0.7[5] km/s
Proper motion (μ) RA: −92.33[1] mas/yr
Dec.: −85.67[1] mas/yr
Parallax (π)11.86 ± 0.16 mas[1]
Distance275 ± 4 ly
(84 ± 1 pc)
Absolute magnitude (MV)−1.55[6]
Details
Radius40[7] R☉
Luminosity711.28[4] L☉
Temperature3,894±59[8] K
Other designations
φ1 Lup, CD−35°10236, FK5 566, HD 136422, HIP 75177, HR 5705, SAO 206552[9]
Database references
SIMBADdata
A light curve for Phi1 Lupi, plotted from Hipparcos data[10]

Phi1 Lupi is a solitary[11] star in the southern constellation of Lupus. It is visible to the naked eye with an apparent visual magnitude of 3.58.[2] Based upon an annual parallax shift of 11.86 mas as seen from Earth, it is located around 275 light years from the Sun. The star is drifting closer with a radial velocity of −29 km/s.[5] It has an absolute magnitude of −1.55.[6]

This is an evolved K-type giant star with a stellar classification of K5 III,[3] which means it has used up its core hydrogen and has expanded. At present it has 40 times the radius of the Sun.[7] It is a variable star of unknown type, with an amplitude of 0.008 in visual magnitude and a period of 4.82 days.[12] The star is radiating 711[4] times the luminosity of the Sun from its enlarged photosphere at an effective temperature of 3,894 K.[8]

  1. ^ a b c d e Cite error: The named reference vanLeeuwen2007 was invoked but never defined (see the help page).
  2. ^ a b c Cite error: The named reference Mermilliod1986 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference houk1979 was invoked but never defined (see the help page).
  4. ^ a b c Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference deBruijne2012 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference Ginestet2000 was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference dr2 was invoked but never defined (see the help page).
  8. ^ a b Cite error: The named reference Strassmeier2000 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference CDS 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 Koen2002 was invoked but never defined (see the help page).