Lambda Capricorni

Lambda Capricorni is a solitary^[7] star in the southern constellation of Capricornus. Its name is a Bayer designation that is Latinized from λ Capricorni, and abbreviated Lamdba Cap or λ Cap. This star is faintly visible to the naked eye with an apparent visual magnitude of +5.56.^[3] Based upon an annual parallax shift of 11.58 mas as seen from the Earth,^[2] the star is located 271 light-years (83 pc) from the Sun. At that distance, the visual magnitude is diminished by an extinction factor of 0.11 due to interstellar dust.^[8] It is drifting closer with a line of sight velocity of −2 km/s.^[2] This star is subject to lunar occultations because of its position near the ecliptic.^[9]

Lambda Capricorni

Location of λ Capricorni (circled)
Observation data Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation	Capricornus[1]
Right ascension	21h 46m 32.097s[2]
Declination	−11° 21′ 57.44″[2]
Apparent magnitude (V)	+5.56[3]
Characteristics
Evolutionary stage	main sequence
Spectral type	A1 V[4]
B−V color index	−0.01[3]
Astrometry
Radial velocity (Rv)	−2.32±0.51[2] km/s
Proper motion (μ)	RA: +29.007 mas/yr[2] Dec.: −9.420 mas/yr[2]
Parallax (π)	12.0253±0.0711 mas[2]
Distance	271 ± 2 ly (83.2 ± 0.5 pc)
Absolute magnitude (MV)	+0.89[1]
Details
Mass	2.50±0.04[2] M☉
Radius	2.21±0.05[2] R☉
Luminosity	48.89+0.8 −0.7[2] L☉
Surface gravity (log g)	3.99+0.02 −0.01[2] cgs
Temperature	10,247+51 −42[2] K
Rotational velocity (v sin i)	192.5±5.7[5] km/s
Age	271±64[2] Myr
Other designations
λ Cap, 48 Cap, BD−12°6087, FK5 818, HD 207052, HIP 107517, HR 8319, SAO 164639[6]
Database references
SIMBAD	data

This is a white-hued A-type main sequence star with a stellar classification of A1 V.^[4] It has been listed as a magnetic Ap star, indicating the spectrum displays chemically peculiar features.^[5] However, its status as a true Ap star is disputed.^[10] The star has an estimated 2.50 times the mass of the Sun and about 2.21 times the Sun's radius.^[2] It is 271^[2] million years old and is spinning rapidly with a projected rotational velocity of 192.5 km/s.^[5] Lambda Capricorni is radiating 49 times the Sun's luminosity from its photosphere at an effective temperature of 10,247 K.^[2]

This star is a member of the HSC 396 cluster of stars, which was discovered in 2023.^[10]