Gamma2 Octantis

{{other stars by Bayer designation|Gamma Octantis{{!}}γ Octantis}}

{{Starbox begin

| name = γ² Octantis

}}

{{Starbox observe

| epoch = J2000.0 (ICRS)

| constell = Octans

| ra = {{RA|23|57|32.8617}}

| dec = {{DEC|-82|10|11.310}}

| appmag_v = 5.72{{±|0.01}}

}}

{{Starbox character

| type = red clump

| class = K0 III

| b-v = +1.05

| u-b = +0.92

}}

{{Starbox astrometry

| radial_v = 27.2{{±|2.9}}

| parallax = 10.1771

| p_error = 0.0345

| parallax_footnote =

| prop_mo_ra = −22.246

| prop_mo_dec = −23.235

| pm_footnote =

| absmag_v = +0.87

}}

{{Starbox detail

| source =

| mass = 1.15{{±|0.15}}

| radius = 10.54{{±|0.28}}

| luminosity = 52.6{{±|1.3}}

| gravity = 2.53{{±|0.13}}

| temperature = 4,788{{±|58}}

| metal_fe = −0.04{{±|0.04}}

| rotational_velocity = 2.8{{±|1.1}}

| age_gyr =

}}

{{Starbox catalog

| names = {{odlist|B = γ² Oct|HD = 224362|CPD = −82°907|HIP = 118114|HR = 9061|SAO = 258996|Gould = 87 G. Octantis}}

}}

{{Starbox reference

| Simbad = gam02+Oct

}}

γ² Octantis, Latinized to Gamma² Octantis (Gamma² Oct), is a solitary star in the southern circumpolar constellation Octans. It has an apparent magnitude of 5.72, allowing it to be faintly seen with the naked eye. Parallax measurements place the object at a distance of 320 light years and is currently receding with a heliocentric radial velocity of {{val|27|ul=km/s}}.

Gamma² Oct has a stellar classification of K0 III, indicating that it is a red giant. At present it has 115% the mass of the Sun but has expanded to 10.54 times its girth. It shines at 52.6 times the luminosity of the Sun from its enlarged photosphere at an effective temperature of {{val|4788|ul=K|fmt=commas}}, giving it a yellow-orange glow. Gamma² Oct has a metallicity around 91% that of the Sun and spins with a projected rotational velocity of about {{val|3|ul=km/s}}.

References

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}}

Category:K-type giants