Pi Ceti

{{Short description|Spectroscopic binary star system in the constellation Cetus}}

{{Starbox begin

| name = Pi Ceti

}}

{{Starbox image

| image=

{{Location mark

|image=Eridanus constellation map.svg|alt=|float=center|width=280

|label=|position=right

|mark=Red circle.svg|mark_width=11|mark_link=α Ceti

|x=790|y=330

}}

|caption=Location of Pi Ceti (circled)

}}

{{Starbox observe

| epoch = J2000.0

| equinox = J2000.0 (ICRS)

| constell = Cetus

| ra = {{RA|02|44|07.34928}}

| dec = {{DEC|−13|51|31.3130}}

| appmag_v = 4.238

}}

{{Starbox character

| class = B7 V or B7 IV

| b-v = −0.130

| u-b = −0.396

| r-i =

| variable =

}}

{{Starbox astrometry

| radial_v =

| prop_mo_ra = −8.62

| prop_mo_dec = −9.07

| parallax = 8.30

| p_error = 0.21

| parallax_footnote =

| absmag_v = −1.16

}}

{{Starbox orbit

| reference =

| period_unitless = {{Val|2722|14|fmt=commas|u=d}}

| eccentricity = {{Val|0.0|0.7}}

| periastron = {{nowrap|2444852 ± 29 JD}}

| periarg = 0.0

| k1 = {{Val|4.33|0.25}}

}}

{{Starbox detail

| source =

| component1 = π Cet A

| mass = {{Val|4.4|0.2}}

| radius = {{Val|4.3|0.3}}

| luminosity = 468

| temperature = {{Val|12900|400|fmt=commas}}

| gravity = {{Val|3.8|0.2}}

| metal_fe = {{Val|0.28|0.16}}

| rotational_velocity = {{Val|20.9|1.2}}

| age_myr = {{Val|0.3|0.1|0.1}}

}}

{{Starbox catalog

| names = π Cet, 89 Ceti, BD−14 519, FK5 97, HD 17081, HIP 12770, HR 811, SAO 148575.

}}

{{Starbox reference

| Simbad = pi+Cet

}}

Pi Ceti, Latinized from π Ceti, is the Bayer designation for a star system in the equatorial constellation of Cetus. It is visible to the naked eye with an apparent visual magnitude of 4.238. Observed to have an Earth half yearly parallax shift of 8.30 mas, it is around 393 light years from the Sun.

This is a single-lined spectroscopic binary system with a nearly circular orbit and a period of 7.45 years. The fact that the system has a negligible eccentricity is surprising for such a long period, and may suggest that the secondary is a white dwarf that had its orbit circularized during a mass-transfer event.

The primary, component A, is a normal B-type star that has been given stellar classifications of B7 V and B7 IV. It appears very young – less than half a million years in age – and may still be on a pre-main sequence track. The star shows no magnetic field but it does emit an infrared excess.

Name

This star, along with ε Cet, ρ Cet and σ Cet, was Al Sufi's Al Sadr al Ḳaiṭos, the Whale's breast/chest (upper torso).{{cite book | last=Allen | first=R. H. | date=1963 | author-link=Richard Hinckley Allen | title=Star Names: Their Lore and Meaning | url=https://archive.org/details/starnamestheirlo00alle/page/162 | access-date=2010-12-12 | edition=Reprint | publisher=Dover Publications Inc. | location=New York | isbn=0-486-21079-0 | page=[https://archive.org/details/starnamestheirlo00alle/page/162 162] | url-access=registration }}

Per Jack Rhoads's Reduced Star Catalog Containing 537 Named Stars, Al Sufi's numerically ordered stars (1 to 4), were ρ (rho), σ (sigma), ε (epsilon) and this star.[https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19720005197_1972005197.pdf Jack W. Rhoads - Technical Memorandum 33-507-A Reduced Star Catalog Containing 537 Named Stars, Jet Propulsion Laboratory, California Institute of Technology; November 15, 1971]

In Chinese, {{lang|zh|天苑}} ({{lang|zh-Latn|Tiān Yuàn}}), meaning Celestial Meadows, refers to an asterism consisting of π Ceti, and 15 stars in Eridanus: γ, π, δ, ε, ζ, η, and the string of τ (Tau)¹, ², ³, ⁴, ⁵, ⁶, ⁷, ⁸ and ⁹. Consequently, the Chinese name for the star is {{lang|zh|天苑七}} ({{lang|zh-Latn|Tiān Yuàn qī}}) meaning Celestial Meadows: seven.{{in lang|zh}} [http://aeea.nmns.edu.tw/2006/0607/ap060712.html AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 12 日] {{Webarchive|url=https://web.archive.org/web/20110522001503/http://aeea.nmns.edu.tw/2006/0607/ap060712.html |date=2011-05-22 }}

References

{{reflist|refs=

{{citation

| title=Validation of the new Hipparcos reduction

| last1=van Leeuwen | first1=F.

| journal=Astronomy and Astrophysics

| volume=474 | issue=2 | pages=653–664 | date=2007

| arxiv=0708.1752 | bibcode=2007A&A...474..653V

| doi=10.1051/0004-6361:20078357 | s2cid=18759600 | postscript=. }}

{{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 | s2cid=119257644 | postscript=. }}

{{citation

| title=Chemical abundances of magnetic and non-magnetic Herbig Ae/Be stars

| display-authors=1 | last1=Folsom | first1=C. P.

| last2=Bagnulo | first2=S. | last3=Wade | first3=G. A.

| last4=Alecian | first4=E. | last5=Landstreet | first5=J. D.

| last6=Marsden | first6=S. C. | last7=Waite | first7=I. A.

| journal=Monthly Notices of the Royal Astronomical Society

| volume=422 | issue=3 | pages=2072–2101 | date=May 2012

| doi=10.1111/j.1365-2966.2012.20718.x | doi-access=free | bibcode=2012MNRAS.422.2072F

| arxiv=1202.1845 | s2cid=119100447 | postscript=. }}

{{citation

| title=The Spectroscopic Orbit of Pi Ceti

| display-authors=1 | last1=Lacy | first1=C. H. S.

| last2=Fekel | first2=F. C. | last3=Mathieu | first3=R. D.

| last4=Morrell | first4=N. I. | last5=Morse | first5=J. A.

| last6=Torres | first6=G. | last7=Willmarth | first7=D.

| journal=Astronomical Journal | postscript=.

| volume=113 | page=1088 | date=March 1997

| doi=10.1086/118325 | bibcode=1997AJ....113.1088L | doi-access=free }}

{{citation

| display-authors=1 | last1=Hohle | first1=M. M.

| last2=Neuhäuser | first2=R. | last3=Schutz | first3=B. F.

| title=Masses and luminosities of O- and B-type stars and red supergiants

| journal=Astronomische Nachrichten

| volume=331 | issue=4 | page=349 | date=April 2010

| doi=10.1002/asna.200911355 | bibcode=2010AN....331..349H

| arxiv=1003.2335 | s2cid=111387483 | postscript=. }}

{{citation

| title=The atmospheric parameters and spectral interpolator for the MILES stars

| journal=Astronomy & Astrophysics

| volume=531 | page=A165 | date=July 2011

| doi=10.1051/0004-6361/201116769 | bibcode=2011A&A...531A.165P

| postscript=. | arxiv=1104.4952 | s2cid=54940439 }}

{{citation

| last=Buscombe | first=W.

| title=Spectral classification of Southern fundamental stars

| journal=Mount Stromlo Observatory Mimeogram

| volume=4 | year=1962

| page=1

| bibcode=1962MtSOM...4....1B | postscript=. }}

{{citation

| display-authors=1 | last1=Gutierrez-Moreno | first1=Adelina

| last2=Moreno | first2=H. | last3=Stock | first3=J.

| last4=Torres | first4=C. | last5=Wroblewski | first5=H.

| title=A System of photometric standards

| journal=Publications of the Department of Astronomy University of Chile | publisher=Publicaciones Universidad de Chile, Department de Astronomy

| volume=1 | pages=1–17 | year=1966

| bibcode=1966PDAUC...1....1G | postscript=. }}

{{citation

| title=pi. Cet -- Spectroscopic binary

| work=SIMBAD Astronomical Database

| publisher=Centre de Données astronomiques de Strasbourg

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

| access-date=2017-02-08 | postscript=. }}

}}

Category:B-type main-sequence stars

Category:Spectroscopic binaries