Upsilon Octantis

{{Starbox begin

| name = υ Octantis

}}

{{Starbox image

| image ={{Location mark

| image=Octans IAU.svg | alt= | float=center | width=250

| label= | position=center

| mark=Red circle.svg | mark_width=7 | mark_link=Upsilon Octantis

| x = 430 | y = 440

}}

| caption = Location of υ Octantis (circled)

}}

{{Starbox observe

| epoch = J2000.0 (ICRS)

| constell = Octans

| ra = {{RA|22|31|37.5152}}

| dec = {{DEC|-85|58|02.110}}

| appmag_v = 5.75{{±|0.01}}

}}

{{Starbox character

| class = K0 III

| b-v = +1.02

| u-b = +0.88

}}

{{Starbox astrometry

| radial_v = 19{{±|7.8}}

| parallax = 9.5042

| p_error = 0.0351

| parallax_footnote =

| prop_mo_ra = −37.556

| prop_mo_dec = +61.431

| pm_footnote =

| absmag_v = +0.77

}}

{{Starbox detail

| source =

| mass = 2.12{{±|0.07}}

| radius = 10.3{{±|0.2}}

| luminosity = 56{{±|1.1}}

| gravity = 2.7{{±|0.1}}

| temperature = 4,910{{±|42}}

| metal_fe = 0.00{{±|0.03}}

| rotational_velocity = 1.5{{±|1.3}}

| age_gyr =

}}

{{Starbox catalog

| names = {{odlist|B = υ Oct|CPD = −86°406|FK5 = 1670|GC = 31327|HD = 211539|HIP = 111196|HR = 8505|SAO = 258932|Gould = 71 G. Octantis}}

}}

{{Starbox reference

| Simbad = ups+Oct

}}

Upsilon Octantis (Upsilon Oct), Latinized from υ Octantis, is a solitary star in the southern circumpolar constellation Octans. It is faintly visible to the naked eye with an apparent magnitude of 5.75 and is located 343 light years away from the Solar System. However, it is receding with a heliocentric radial velocity of {{val|19|ul=km/s}}.

Upsilon Oct has a stellar classification of K0 III, indicating that it is a red giant. At present it has 2.12 times the mass of the Sun but has expanded to 10.3 times its girth. It shines with a luminosity of {{val|56|ul=solar luminosity}} from its enlarged photosphere at an effective temperature of {{val|4910|ul=K|fmt=commas}}, giving a yellowish orange hue when viewed at night. Upsilon Oct has a solar metallicity, with an iron abundance equivalent to the Sun's. It spins leisurely with a poorly-constrained projected rotational velocity of {{val|1.5|ul=km/s}}.

References

{{reflist||refs=

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{{cite journal |last1=Johnson |first1=H. L. |last2=Mitchell |first2=R. I. |last3=Iriarte |first3=B. |last4=Wisniewski |first4=W. Z. |title=UBVRIJKL Photometry of the Bright Stars |journal=Communications of the Lunar and Planetary Laboratory |date=1966 |volume=4 |pages=99–110 |bibcode=1966CoLPL...4...99J}}

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{{cite journal |last1=Anderson |first1=E. |last2=Francis |first2=Ch. |title=XHIP: An extended hipparcos compilation |journal=Astronomy Letters |date=May 2012 |volume=38 |issue=5 |pages=331–346 |doi=10.1134/S1063773712050015 |language=en |issn=1063-7737 |bibcode=2012AstL...38..331A |arxiv=1108.4971|s2cid=119257644 }}

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{{cite journal |last1=Ottoni |first1=G. |last2=Udry |first2=S. |last3=Ségransan |first3=D. |last4=Buldgen |first4=G. |last5=Lovis |first5=C. |last6=Eggenberger |first6=P. |last7=Pezzotti |first7=C. |last8=Adibekyan |first8=V. |last9=Marmier |first9=M. |last10=Mayor |first10=M. |last11=Santos |first11=N. C. |last12=Sousa |first12=S. G. |last13=Lagarde |first13=N. |last14=Charbonnel |first14=C. |title=CORALIE radial-velocity search for companions around evolved stars (CASCADES): I. Sample definition and first results: Three new planets orbiting giant stars |journal=Astronomy & Astrophysics |date=January 2022 |volume=657 |pages=A87 |doi=10.1051/0004-6361/202040078 |issn=0004-6361 |bibcode=2022A&A...657A..87O |arxiv=2201.01528 |doi-access=free}}

{{cite journal | last=Gould | first=Benjamin Apthorp | title=Uranometria Argentina : brillantez y posicion de las estrellas fijas, hasta la septima magnitud, comprendidas dentro de cien grados del polo austral : con atlas | journal=Resultados del Observatorio Nacional Argentino | volume=1 | bibcode=1879RNAO....1.....G | year=1878 | page=}}

{{cite journal | last1 = Eggleton | first1 = P. P. | last2 = Tokovinin | first2 = A. A. | title = A catalogue of multiplicity among bright stellar systems | journal = Monthly Notices of the Royal Astronomical Society | date = 11 September 2008 | volume = 389 | issue = 2 | pages = 869–879 | issn = 0035-8711 | eissn = 1365-2966 | doi = 10.1111/j.1365-2966.2008.13596.x | bibcode = 2008MNRAS.389..869E | arxiv = 0806.2878 | doi-access = free }}

}}

Category:K-type giants