en>K9re11: removed Category:Group theory using HotCat as there are already more specific subcategories

2014-11-15T20:16:48Z

removed Category:Group theory using HotCat as there are already more specific subcategories

en>Qetuth: more specific stub type

2012-01-01T10:36:04Z

more specific stub type

New page

{{Starbox 2
| name=α Caeli
| image=[[File:Caelum constellation map.png|250px]]
| caption=Alpha Caeli is at lower center.
| constell=[[Caelum (constellation)|Caelum]]
| epoch=[[J2000.0]] ([[International Celestial Reference System|ICRS]])
| equinox=[[J2000.0]]
| component_a=A
| component_b=B
| ra_a_h=04
| ra_a_m=40
| ra_a_s=33.7125
| radec_a_footnote=<ref name="hipparcos">{{cite journal
| author=Perryman, M. A. C. ''et al''
| title=The HIPPARCOS Catalogue
| journal=Astronomy & Astrophysics | volume=323
| pages=L49–L52 |date=April 1997
| bibcode=1997A&A...323L..49P }}</ref>
| dec_a_d=–41
| dec_a_m=51
| dec_a_s=49.509
| appmag_v_a=4.456
| class_a=F2V<ref name="aj132">{{cite journal
| author=Gray, R. O. | coauthors=''et al''.
| title=Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 pc-The Southern Sample |date=July 2006
| journal=The Astronomical Journal | volume=132
| issue=1 | pages=161–170 | doi=10.1086/504637 | bibcode=2006AJ....132..161G |arxiv = astro-ph/0603770 }}</ref>
| b-v_a=+0.34<ref name="clpl4">{{cite journal
| author=Johnson, H. L.; Iriarte, B.; Mitchell, R. I.; Wisniewskj, W. Z.
| title=UBVRIJKL photometry of the bright stars
| journal=Communications of the Lunar and Planetary Laboratory | volume=4 | issue=99 | year=1966
| bibcode=1966CoLPL...4...99J }}</ref>
| u-b_a=+0.01<ref name="clpl4" />
| radial_v_a={{nowrap|–0.6 ± 0.9}}<ref>{{cite conference
| last=Evans | first=D. S.
| title=The Revision of the General Catalogue of Radial Velocities
| booktitle=Determination of Radial Velocities and their Applications, Proceedings from IAU Symposium no. 30 | location=University of Toronto
| date=June 20–24, 1966 | publisher=Academic Press
| bibcode=1967IAUS...30...57E
| accessdate=2009-09-24 }}</ref>
| prop_mo_ra_a=–141.18<ref name="hipparcos" />
| prop_mo_dec_a=–74.95<ref name="hipparcos" />
| parallax=49.67
| p_error=0.53
| parallax_footnote=<ref name="hipparcos" />
| absmag_v_a=3.39<ref>{{cite journal
| last=Reiners | first=A.
| title=Rotation- and temperature-dependence of stellar latitudinal differential rotation
| journal=Astronomy and Astrophysics| volume=446
| issue=1 |date=January 2006
| pages=267–277 | doi=10.1051/0004-6361:20053911 | bibcode=2006A&A...446..267R|arxiv = astro-ph/0509399 }}</ref>
| mass_a=1.48<ref name="aaa418" />
| radius_a=1.3<ref name="aaa367" />
| temperature_a=6,991<ref name="aj132" />
| metal_a=<math>\begin{smallmatrix}\left[\frac{M}{H}\right]\ =\ -0.10\end{smallmatrix}</math><ref name="aj132" />
| gravity_a=4.01<ref name="aj132" />
| rotational_v_a={{nowrap|47.8 ± 2.4}}<ref name="aaa412" />
| age_a={{nowrap|0.9 (0.7–1.3) × 10<sup>9</sup>}}<ref name="aaa418" />
| names='''A''': [[Catalog of Components of Double and Multiple Stars|CCDM]] J04406-4152A, [[Bonner Durchmusterung|CD]]−42°1587, [[Bonner Durchmusterung|CPD]]−42°513, [[Fifth Fundamental Catalogue|FK5]] 1129, GC 5708, [[Gliese-Jahreiss catalogue|Gl]] 174.1 A, [[Gliese-Jahreiss catalogue|GJ]] 9164 A, [[Henry Draper Catalogue|HD]] 29875, [[Hipparcos catalogue|HIP]] 21770, [[Harvard Revised catalogue|HR]] 1502, [[Index Catalogue of Double Stars|IDS]] 04373-4203 A, [[Smithsonian Astrophysical Observatory catalogue|SAO]] 216926.<ref>[http://simbad.u-strasbg.fr/simbad/sim-id?Ident=alf+cae * alf Cae -- Star in double system], database entry, [[SIMBAD]]. Accessed on line November 4, 2009.</ref><br />'''B''': [[Catalog of Components of Double and Multiple Stars|CCDM]] J04406-4152B, [[Bonner Durchmusterung|CD]]−42°1587B, [[Bonner Durchmusterung|CPD]]−42°513B, [[Gliese-Jahreiss catalogue|Gl]] 174.1 B, [[Gliese-Jahreiss catalogue|GJ]] 9164 B, [[Index Catalogue of Double Stars|IDS]] 04373-4203 B.<ref name=sb1 />
| simbad_a=alf+cae
| ra_b_h=04
| ra_b_m=40
| ra_b_s=34.0
| dec_b_d=−41
| dec_b_m=51
| dec_b_s=51
| radec_b_footnote=<ref name=sb1 />
| prop_mo_ra_b=−147<ref name=sb1 />
| prop_mo_dec_b=−78<ref name=sb1 />
| class_b=M0.5<ref name=sb1 />
| radial_v_b=−0.6 ± 0.9<ref name=sb1 />
| appmag_v_b= 12.5<ref name=sb1 />
| radec_b_footnote=<ref name=sb1>[http://simbad.u-strasbg.fr/simbad/sim-id?Ident=alf+cae+b GJ 174.1 B -- Flare Star], database entry, [[SIMBAD]]. Accessed on line November 5, 2009.</ref>
| mass_b=0.3<ref name=kaler>[http://stars.astro.illinois.edu/sow/alphacae.html Alpha Cae], ''Stars'', Jim Kaler. Accessed on line November 5, 2009.</ref>
| temperature_b=3800<ref name=kaler />
| simbad_b=alf+cae+b
}}

'''Alpha Caeli''' (α Cae, α Caeli) is a [[double star]] system in the [[constellation]] [[Caelum]].

Alpha Caeli A is an [[F-type main sequence star]] with a [[stellar classification]] of F2V and an [[apparent magnitude]] of +4.44. It has 1.48 times the [[solar mass|mass of the Sun]]<ref name="aaa418" /> and 1.3 times the [[solar radius]].<ref name="aaa367">{{cite journal
| author=Pasinetti Fracassini, L. E.; Pastori, L.; Covino, S.; Pozzi, A.
| title=Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third edition - Comments and statistics
| journal=Astronomy and Astrophysics | volume=367
| issue=2
| pages=521–524 |date=February 2001
| doi=10.1051/0004-6361:20000451 | bibcode=2001A&A...367..521P|arxiv = astro-ph/0012289 }}</ref> The [[stellar rotation|projected rotational velocity]] at the stellar equator is 47.8 km/s.<ref name="aaa412">{{cite journal
| author=Reiners, A.; Schmitt, J. H. M. M.
| title=Differential rotation in rapidly rotating F-stars
| journal=Astronomy and Astrophysics | volume=412
| issue=3
| pages=813–819 |date=December 2003
| doi=10.1051/0004-6361:20034255 | bibcode=2003A&A...412..813R|arxiv = astro-ph/0309616 }}</ref> It is suspected of being a [[Delta Scuti variable]] star.<ref>{{cite journal
| last=Petit | first=M. |date=November 1977
| title=Etoiles Proches Suspectees de Variabilite
| journal=Information Bulletin on Variable Stars
| volume=1362 | pages=1–3
| bibcode=1977IBVS.1362....1P
| accessdate=2009-09-24 }}</ref>

The companion is a spectral class M0.5V [[red dwarf]] star with [[absolute magnitude]] 9.80.<ref>{{cite journal
| author=Hawley, Suzanne L.; Gizis, John E.; Reid, Neill I. | title=Erratum: The Palomar/MSU Nearby Star Spectroscopic Survey.II.The Southern M Dwarfs and Investigation of Magnetic Activity
| journal=Astronomical Journal | volume=113
| page=1458 |date=April 1997
| doi=10.1086/118363 | bibcode=1997AJ....113.1458H}}</ref> It is a [[UV Ceti variable]] star that undergoes random increases in luminosity.<ref>{{cite journal
| author=Gershberg, R. E. | coauthors=''et al''.
| title=Catalogue and bibliography of the UV Cet-type flare stars and related objects in the solar vicinity |date=November 1999
| journal=Astronomy and Astrophysics Supplement
| volume=139
| issue=3 | pages=555–558
| doi=10.1051/aas:1999407 | bibcode=1999A&AS..139..555G }}</ref> This star is currently separated from the primary by an angle of 6.6 [[arcsecond]]s, which indicates an orbit with a [[semimajor axis]] whose expected value is 206 [[astronomical unit|AU]].<ref>{{cite journal
| author=Poveda, A. | coauthors=''et al''.
| title=Statistical studies of visual double and multiple stars. II. A catalogue of nearby wide binary and multiple systems |date=April 1994
| journal=Revista Mexicana Astronomía y Astrofísica
| volume=28 | issue=1 | pages=43–89
| bibcode=1994RMxAA..28...43P
| accessdate=2009-09-24 }}</ref>

Alpha Caeli is approximately 65.7 [[light years]] from [[Earth]] and is an estimated 900 million years old. The [[Space velocity (astronomy)|space velocity]] components of this system are U = 10, V = 6 and W = -10 km/s. It is orbiting the [[Milky Way]] galaxy at an average distance of 8.006 kpc from the core and with an [[orbital eccentricity]] of 0.07. This orbit lies close to the galactic plane, and the system travels no more than 0.05 kpc above or below this plane.<ref name="aaa418">{{cite journal
| last=Holmberg | first=J. | coauthors=''et al''.
| title=The Geneva-Copenhagen survey of the Solar neighbourhood II. New uvby calibrations and rediscussion of stellar ages, the G dwarf problem, age-metallicity diagram, and heating mechanisms of the disk
| journal=Astronomy and Astrophysics | volume=475
| issue=2
| pages=519–537 |date=November 2007
| doi=10.1051/0004-6361:20077221 | bibcode=2007A&A...475..519H |arxiv = 0707.1891 }} See the [http://vizier.cfa.harvard.edu/viz-bin/VizieR-5?-out.add=.&-source=V/117A/newcat&recno=3027 entry for HIP 21770] in the [[VizieR]] table with [[Centre de Données astronomiques de Strasbourg|CDS]] ID [http://vizier.cfa.harvard.edu/viz-bin/Cat?V/117A V/117A].</ref> Alpha Caeli is probably a member of the [[Ursa Major moving group]] of stars that have similar kinematic properties and probably originated from the same [[star cluster]].<ref>{{cite journal
| author=King, Jeremy R. | coauthors=''et al''.
| title=Stellar Kinematic Groups. II. A Reexamination of the Membership, Activity, and Age of the Ursa Major Group
| journal=The Astronomical Journal | volume=125
| issue=4 | pages=1980–2017 |date=April 2003 | doi=10.1086/368241 | bibcode=2003AJ....125.1980K }}</ref>

==References==
{{reflist|2}}
{{Nearest bright star systems|7.}}
{{Stars of Caelum}}

[[Category:Bayer objects|Caeli, Alpha]]
[[Category:Caelum (constellation)]]
[[Category:F-type main-sequence stars]]
[[Category:Henry Draper Catalogue objects|29875]]
[[Category:Hipparcos objects|021770]]
[[Category:Durchmusterung objects|CD-42 1587]]
[[Category:Binary stars]]

CEP subgroup - Revision history

en>K9re11: removed Category:Group theory using HotCat as there are already more specific subcategories

en>Qetuth: more specific stub type