epsilon Piscis Austrini

This is a B-type main sequence star with a stellar classification of B8 Ve. It is a Be star that is spinning rapidly with a projected rotational velocity of 216 km/s, compared to an equatorial critical velocity of 301 km/s. The star has 6.0 times the mass of the Sun, 7.5 times the Sun's radius, and is radiating 661 times the solar luminosity from its photosphere at an effective temperature of 11,066 K.

Epsilon Piscis Austrini is part of a wide binary star system, the companion is likely a low-mass red dwarf with a projected separation of 11,700 astronomical units. It also exhibits a strong discrepancy between proper motion measurements taken by the Hipparcos and Gaia satellites, hinting the presence of an astrometric companion, possibly a solar-mass star, with a separation between 6 and 30 au.

The star is moving through the Galaxy at 18.7 km/s relative to the Sun. Its projected Galactic orbit carries it between {{convert|7333|pc|ly|0|disp=output number only}} and {{convert|8627|pc|ly|0|disp=out|abbr=off}} from the center of the Galaxy.

In Chinese, {{lang|zh|羽林軍}} ({{lang|zh-Latn|Yǔ Lín Jūn}}), meaning Palace Guard, refers to an asterism consisting of:

{{cols|rules=yes|colwidth=8em}}

• ε Piscis Austrini
• 29 Aquarii
• 35 Aquarii
• 41 Aquarii
• 47 Aquarii
• 49 Aquarii
• λ Piscis Austrini
• HD 212448
• 21 Piscis Austrini
• 20 Piscis Austrini
• υ Aquarii
• 68 Aquarii
• 66 Aquarii
• 61 Aquarii
• 53 Aquarii
• 50 Aquarii
• 56 Aquarii
• 45 Aquarii
• 58 Aquarii
• 64 Aquarii
• 65 Aquarii
• 70 Aquarii
• 74 Aquarii
• τ² Aquarii
• τ¹ Aquarii
• δ Aquarii
• 77 Aquarii
• 88 Aquarii
• 89 Aquarii
• 86 Aquarii
• 101 Aquarii
• 100 Aquarii
• 99 Aquarii
• 98 Aquarii
• 97 Aquarii
• 94 Aquarii
• ψ³Aquarii
• ψ²Aquarii
• ψ¹Aquarii
• 87 Aquarii
• 85 Aquarii
• 83 Aquarii
• χ Aquarii
• ω¹ Aquarii
• ω² Aquarii

{{colend}}

Consequently, the Chinese name for ε Piscis Austrini itself is {{lang|zh|羽林軍八}} ({{lang|zh-Latn|Yǔ Lín Jūn bā}}, {{langx|en|the Eighth Sixth Star of Palace Guard}}.){{in lang|zh}} [http://aeea.nmns.edu.tw/2006/0607/ap060707.html AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 7 日] {{Webarchive|url=https://web.archive.org/web/20110521232711/http://aeea.nmns.edu.tw/2006/0607/ap060707.html |date=2011-05-21 }}

{{reflist|refs=

{{Cite DR3|6622561673163882752 }}

{{citation

| last1=Anderson | first1=E. | last2=Francis | first2=Ch.

| title=XHIP: An extended hipparcos compilation

| journal=Astronomy Letters | postscript=.

| volume=38 | issue=5 | pages=331 | year=2012

| bibcode=2012AstL...38..331A | arxiv=1108.4971

| doi=10.1134/S1063773712050015 | s2cid=119257644 }}

{{Citation |last=Kervella |first=Pierre |last2=Arenou |first2=Frédéric |last3=Thévenin |first3=Frédéric |date=January 2022 |title=Stellar and substellar companions from Gaia EDR3. Proper-motion anomaly and resolved common proper-motion pairs |journal=Astronomy and Astrophysics |language=en |volume=657 |pages=A7 |doi=10.1051/0004-6361/202142146 |doi-access=free |bibcode=2022A&A...657A...7K |arxiv=2109.10912 |issn=0004-6361 |postscript=.}} Radius and mass are available only in the [https://vizier.cds.unistra.fr/viz-bin/VizieR?-source=J/A%2BA/657/A7&HIP=111954 VizieR catalog].

{{citation

| title=XHIP: An extended hipparcos compilation

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{{citation

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}}

{{citation

| last1=Abt | first1=Helmut A. | last2=Levato | first2=Hugo | last3=Grosso | first3=Monica

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| journal=The Astrophysical Journal | postscript=.

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{{citation

| last1=Feinstein | first1=A. | last2=Marraco | first2=H. G.

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| volume=84 | pages=1713–1725 | date=November 1979

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{{citation

| title=eps PsA -- Be Star

| work=SIMBAD Astronomical Database

| publisher=Centre de Données astronomiques de Strasbourg

| url=http://simbad.u-strasbg.fr/simbad/sim-id?Ident=eps+PsA

| accessdate=2017-05-18 | postscript=. }}

}}

{{Stars of Piscis Austrinus|state=collapsed}}

{{DEFAULTSORT:Epsilon Piscis Austrini}}

Category:B-type main-sequence stars

Category:Be stars

Category:Piscis Austrinus

Piscis Austrini, Epsilon

Category:Durchmusterung objects

Piscis Austrini, 18

214748

111954

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