Lambda Scorpii

λ Scorpii
Location of λ Scorpii (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Scorpius
Pronunciation /ˈʃɔːlə/[1][2]
Right ascension 17h 33m 36.520s[3]
Declination −37° 06′ 13.76″[3]
Apparent magnitude (V) 1.62 + 14.9 + 12.0[3][4]
Characteristics
Spectral type B1.5IV + B2IV[5][6]
U−B color index −0.880[7]
B−V color index −0.240[7]
Variable type Beta Cephei (A)[8]
Astrometry
Radial velocity (Rv)−3.00[9] km/s
Proper motion (μ) RA: −8.90[3] mas/yr[3]
Dec.: −29.95 mas/yr[3]
Parallax (π)5.71 ± 0.90 mas[3]
Distanceapprox. 570 ly
(approx. 180 pc)
Absolute magnitude (MV)−3.70[10]
Orbit[11]
PrimaryA
CompanionB
Period (P)2.8825 yr
Semi-major axis (a)49.3 mas
Eccentricity (e)0.121
Inclination (i)77.2°
Orbit[11]
PrimaryAa
CompanionAb
Period (P)5.9520 d
Eccentricity (e)0.26
Semi-amplitude (K1)
(primary)		39.3 km/s
Details
λ Sco Aa
Mass10.4[5] M☉
Radius8.8±1.2[8] R☉
Luminosity36,300[8] L☉
Surface gravity (log g)3.8[6] cgs
Temperature25,000±1,000[8] K
Rotation3.4±0.5 d[8]
Rotational velocity (v sin i)150[8] km/s
λ Sco B
Mass8.1[5] M☉
Radius4.7±1.0[8] R☉
Surface gravity (log g)4.0[6] cgs
Temperature25,000±1,000[8] K
λ Sco Ab
Mass1.8[5] M☉
Other designations
Shaula, 35 Scorpii, 35 Sco, CD−37 11673, FK5 652, HD 158926, HIP 85927, HR 6527, SAO 208954, CCDM J17336-3706A/B/C
Database references
SIMBADdata

Lambda Scorpii is a triple star system and the second-brightest object in the constellation of Scorpius. It is formally named Shaula; Lambda Scorpii is its Bayer designation, which is Latinised from λ Scorpii and abbreviated Lambda Sco or λ Sco. With an apparent visual magnitude of 1.62, it is one of the brightest stars in the night sky.

  1. ^ Cite error: The named reference Kunitzsch was invoked but never defined (see the help page).
  2. ^ Cite error: The named reference IAU-CSN was invoked but never defined (see the help page).
  3. ^ a b c d e f Cite error: The named reference hipparcos was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference REED was invoked but never defined (see the help page).
  5. ^ a b c d Cite error: The named reference tango was invoked but never defined (see the help page).
  6. ^ a b c Cite error: The named reference variability was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference hamdy was invoked but never defined (see the help page).
  8. ^ a b c d e f g h Cite error: The named reference handler was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference Gontcharov2006 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference balona was invoked but never defined (see the help page).
  11. ^ a b Cite error: The named reference msc was invoked but never defined (see the help page).