Iota Lupi

ι Lupi
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Lupus
Right ascension 14h 19m 24.22219s[1]
Declination −46° 03′ 29.1437″[1]
Apparent magnitude (V) 3.54[2]
Characteristics
Spectral type B2.5 IV[3]
U−B color index −0.742[2]
B−V color index −0.180[2]
Astrometry
Radial velocity (Rv)21.6±4.1[4] km/s
Proper motion (μ) RA: −12.56[1] mas/yr
Dec.: −4.76[1] mas/yr
Parallax (π)9.65 ± 0.20 mas[1]
Distance338 ± 7 ly
(104 ± 2 pc)
Absolute magnitude (MV)−1.48[5]
Details
Mass6.9±0.1[6] M☉
Radius4.05±0.33[7] R☉
Luminosity (bolometric)2,082[8] L☉
Surface gravity (log g)3.94±0.07[7] cgs
Temperature18,605±221[7] K
Metallicity [Fe/H]+0.19±0.15[7] dex
Rotational velocity (v sin i)370[9] km/s
Age20.3±4.8[6] Myr
Other designations
ι Lup, CD−45° 9084, HD 125238, HIP 69996, HR 5354, SAO 224833.[10]
Database references
SIMBADdata

ι Lupi, Latinised as Iota 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 3.54.[2] Based upon an annual parallax shift of 9.65 mas as seen from Earth, it is located around 338 light years from the Sun. At that distance, the visual magnitude of the star is diminished by an extinction factor of 0.23 due to interstellar dust.[5] Relative to its neighbors, this star has a peculiar velocity of 27.4±4.9 km/s.[6] It appears to be a member of the Scorpio-Centaurus OB association.[12]

This star has the spectrum of a B-type subgiant star with a stellar classification of B2.5 IV,[3] which may indicate that it has used up its core supply of hydrogen and has begun to expand off the main-sequence. It is rotating rapidly with a projected rotational velocity of 370 km/s.[9] This is giving the star an oblate shape with an equatorial bulge that is an estimated 12% larger than the polar radius.[13] It is about 20[6] million years old with 6.9[6] times the mass of the Sun and 4[7] times the Sun's radius. The star radiates 2,082[8] times the solar luminosity from its outer atmosphere at an effective temperature of 18,605[7] K.

  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 d Cite error: The named reference apjs15 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference Hiltner1969 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 Gontcharov2012 was invoked but never defined (see the help page).
  6. ^ a b c d e Cite error: The named reference Tetzlaff2011 was invoked but never defined (see the help page).
  7. ^ a b c d e f Cite error: The named reference Fitzpatrick2005 was invoked but never defined (see the help page).
  8. ^ a b Cite error: The named reference Hohle2010 was invoked but never defined (see the help page).
  9. ^ a b Cite error: The named reference UesugiFukuda70 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 deGeus1989 was invoked but never defined (see the help page).
  13. ^ Cite error: The named reference belle2012 was invoked but never defined (see the help page).