| appmag_v = 6.21[7]
}}{{Starbox character
| class = F7 IV-V[8]
| b-v = +0.55[7]
| u-b = +0.07[7]
| r-i =
| variable =
}}{{Starbox astrometry
| component1 = λ1 Tuc A
| radial_v = {{Val|+29.4|0.2}}[11]
| prop_mo_ra = {{val|3.849|0.050}}[1]
| prop_mo_dec = {{val|−67.462|0.040}}[1]
| parallax = 16.4907
| p_error = 0.0293
| parallax_footnote = [1]
| absmag_v = +2.68[15]
| component2 = λ1 Tuc B
| radial_v2 =
| prop_mo_ra2 = {{val|9.966|0.062}}[4]
| prop_mo_dec2 = {{val|−79.096|0.052}}[4]
| parallax2 = 16.5242
| p_error2 = 0.0361
| parallax_footnote2 = [4]
| absmag_v2 =
}}{{Starbox detail
| source =
| component1 = λ1 Tuc A
| mass = 1.55[19]
| radius =
| luminosity = 7[20]
| temperature = 6,325[21]
| gravity = 3.90[21]
| metal_fe = +0.09[21]
| rotational_velocity =
| rotation =
| age_gyr = 2.6[21]
| component2 = λ1 Tuc B
| mass2 = 1.38[19]
}}{{Starbox catalog
| names = {{odlist | name=DUN 2 | B=λ1 Tuc | CCDM=J00524-6930AB | WDS=J00524-6930AB }}[26]
| component1 = λ1 Tuc A
| names1 = {{odlist | B=λ1 Tucanae A | CPD=−70 37 | HD=5190 | HIP=4084 | HR=252 | SAO=248269 | WDS=J00524-6930A }}[26]
| component2 = λ1 Tuc B
| names2 = {{odlist | B=λ1 Tucanae B | CPD=−70 38 | HD=5208 | HIP=4088 | SAO=248271 | WDS=J00524-6930B }}[26]
}}{{Starbox reference
| Simbad = lam01+Tuc
}}{{Starbox end}}Lambda1 Tucanae is the Bayer designation for a pair of stars sharing a common proper motion[19] through space, 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°.[ Together, they are barely visible to the naked eye with a combined apparent visual magnitude of 6.21.[7] Based upon an annual parallax shift for both stars of approximately 16.5[1][4] 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[ F-type star with a stellar classification of F7 IV-V.[8] The luminosity class may indicate that, at the age of 2.6 billion years,[21] it is beginning to evolve away from the main sequence. It has an estimated 1.55[19] times the mass of the Sun and is radiating 7[20] times the solar luminosity from its photosphere at an effective temperature of 6,325 K.[21] The magnitude 7.35][ companion, component B, has 1.38[19] times the mass of the Sun. If the pair are gravitationally bound, then their estimated orbital period is 27,000 years.[19]]
References
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7. ^1 {{citation | title=XHIP: An extended hipparcos compilation | last1=Anderson | first1=E. | last2=Francis | first2=Ch. | journal=Astronomy Letters | volume=38 | issue=5 | pages=331 | year=2012 | bibcode=2012AstL...38..331A | doi=10.1134/S1063773712050015 | arxiv=1108.4971 | postscript=. }}
8. ^1 2 3 4 5 6 {{cite DR2|4691995692046507520}}
9. ^1 2 3 4 5 6 {{cite DR2|4691996001284152576}}
10. ^1 2 3 {{cite simbad | title=Lambda1 Tucanae | accessdate=2018-11-26}}