Lambda1 Tucanae

This article is about Lambda1 Tucanae. For other stars with this Bayer designation, see Lambda Tucanae.
Lambda1 Tucanae
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Tucana
A
Right ascension 00h 52m 24.5198s[1]
Declination −69° 30′ 13.5440″[1]
Apparent magnitude (V) 6.70[2]
B
Right ascension 00h 52m 28.3487s[3]
Declination −69° 30′ 10.3819″[3]
Apparent magnitude (V) 7.35[2]
Characteristics
A
Spectral type F7 IV-V[4]
U−B color index +0.07[5]
B−V color index +0.55[5]
B
Spectral type G0/2V[4]
Astrometry
A
Radial velocity (Rv)+29.4±0.2[6] km/s
Proper motion (μ) RA: 3.849±0.050[1] mas/yr
Dec.: −67.462±0.040[1] mas/yr
Parallax (π)16.4907 ± 0.0293 mas[1]
Distance197.8 ± 0.4 ly
(60.6 ± 0.1 pc)
Absolute magnitude (MV)+2.68[7]
B
Proper motion (μ) RA: 9.966±0.062[3] mas/yr
Dec.: −79.096±0.052[3] mas/yr
Parallax (π)16.5242 ± 0.0361 mas[3]
Distance197.4 ± 0.4 ly
(60.5 ± 0.1 pc)
Details
A
Mass1.55[8] M☉
Luminosity7[9] L☉
Surface gravity (log g)3.90[10] cgs
Temperature6,325[10] K
Metallicity [Fe/H]+0.09[10] dex
Age2.6[10] Gyr
B
Mass1.38[8] M☉
Radius1.86[3] R☉
Luminosity3.534[3] L☉
Surface gravity (log g)3.94[11] cgs
Temperature5,797[3] K
Metallicity [Fe/H]+0.04[11] dex
Rotational velocity (v sin i)3.6[12] km/s
Other designations
DUN 2, CCDM J00524-6930AB, WDS J00524-6930AB[13]
A: λ1 Tucanae, CPD−70 37, HD 5190, HIP 4084, HR 252, SAO 248269[13]
B: CPD−70 38, HD 5208, HIP 4088, SAO 248271[13]
Database references
SIMBADdata
companion

Lambda1 Tucanae is the Bayer designation for one member of a pair of stars sharing a common proper motion through space,[8] which lie within the southern constellation of Tucana. As of 2013, the pair had an angular separation of 20.0 arc seconds along a position angle of 82°.[2] Together, they are barely visible to the naked eye with a combined apparent visual magnitude of 6.21.[5] Based upon an annual parallax shift for both stars of approximately 16.5[1][3] mas as seen from Earth, this system is located roughly 198 light years from the Sun.

The brighter member, component A, is a magnitude 6.70[2] F-type star with a stellar classification of F7 IV-V.[4] The luminosity class may indicate that, at the age of 2.6 billion years,[10] it is beginning to evolve away from the main sequence. It has an estimated 1.55[8] times the mass of the Sun and is radiating 7[9] times the solar luminosity from its photosphere at an effective temperature of 6,325 K.[10] The magnitude 7.35[2] companion, component B, has 1.38[8] times the mass of the Sun. If the pair are gravitationally bound, then their estimated orbital period is 27,000 years.[8]

  1. ^ a b c d e f Cite error: The named reference Gaia DR2 A was invoked but never defined (see the help page).
  2. ^ a b c d e Cite error: The named reference WDSC2014 was invoked but never defined (see the help page).
  3. ^ a b c d e f g h i Cite error: The named reference Gaia DR2 B was invoked but never defined (see the help page).
  4. ^ a b c Cite error: The named reference houk1979 was invoked but never defined (see the help page).
  5. ^ a b c Cite error: The named reference Cousins1971 was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference deBruijne2012 was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  8. ^ a b c d e f Cite error: The named reference Tokovinin2014 was invoked but never defined (see the help page).
  9. ^ a b Cite error: The named reference Mcdonald2012 was invoked but never defined (see the help page).
  10. ^ a b c d e f Cite error: The named reference Casagrande2011 was invoked but never defined (see the help page).
  11. ^ a b Cite error: The named reference cassagrande2011 was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference globocki2005 was invoked but never defined (see the help page).
  13. ^ a b c Cite error: The named reference Simbad was invoked but never defined (see the help page).