Beta Tucanae

Starbox short
name=β¹^,² Tucanae
epoch=J2000.0
constell=Tucana
ra=00^h 31^m 32.7^s
dec=−62° 57' 29"
spectral=AB: A2V+B9V
CD: A2V+A7V
appmag_v=β¹: +4.36
β²: +4.53
dist_ly=140 ± 3
dist_pc=43 ± 1
names=HR 126 + HR 126,
HD 2884 + HD 2885,
CP-63 50, HIP 2484 +
HIP 2487, SAO 248201 +
SAO 248202, GC 625,
CCDM 00316-6258

Beta Tucanae (β Tuc / β Tucanae) is a group of six stars which appear to be at least loosely bound into a system in the constellation Tucana. Three of the stars are luminous enough to have been given their own Bayer designations, β¹ Tucanae through β³ Tucanae. The system is approximately 140 light years from Earth.

β¹^,² Tucanae

The two brightest stars, Beta-1 Tucanae and Beta-2 Tucanae, also referred to as Beta Tucanae A and Beta Tucanae C, are 27 arcseconds, or at least 1100 Astronomical Units (AU) apart. They are both main sequence dwarfs, Beta-1 a blue-white B-type star with an apparent magnitude of +4.36, and Beta-2 a white A-type star with an apparent magnitude of +4.53.

Both of these bright stars have at least one closer main sequence companion. Beta Tucanae B is a magnitude +13.5 A-type star which is a close companion to Beta-1, being 2.4 arcseconds, or at least 100 AU away. Beta-2's companion, the 6th magnitude Beta Tucanae D is another A-type star which is separated by approximately 0.38 arcseconds (16 AU) from Beta-2.

β³ Tucanae

Starbox short
name=β³ Tucanae
epoch=J2000.0
constell=Tucana
ra=00^h 32^m 43.8^s
dec=−63° 01' 52"
spectral=A0V+A2V
appmag_v="combined": +5.07
AB: 5.8 + 6.0
dist_ly=152 ± 3
dist_pc=46 ± 1
names=HR 136, HD 3003,
CP-63 52, HIP 2578,
SAO 248208, GC 651,
CCDM 00327-6302

Beta-3 Tucanae is a binary star which is separated from Beta-1 and Beta-2 Tucanae by 9 arcminutes on the sky, which puts the two systems at least 23 000 Astronomical Units (AU) or 0.37 light years apart. It's not clear how tightly Beta-3 Tucanae is gravitationally bound to the rest of the β Tucanae system, but all the stars have similar distances from Earth and have the same proper motion on the sky, indicating they are gravitationally influencing each other to some degree.

Both components of the binary system are white A-type main sequence dwarfs and they have apparent magnitudes of +5.8 and +6.0. They are separated by 0.1 arcseconds, or at least 4 Astronomical Units.