Star in the constellation Fornax
Chi1 Fornacis , Latinised from χ1 Fornacis is a solitary white-hued star located in the southern constellation Fornax . It is barely visible to the naked eye with an apparent magnitude of 6.39,[ 2] which is near the limit for naked eye visibility. Gaia DR3 parallax measurements imply a distance of 339 light-years [ 1] and it is currently drifitng away with a heliocentric radial velocity of 19.0 km/s .[ 6] At its current distance, Chi1 Fornacis' brightness is diminshed by an interstellar extinction of 0.08 magnitudes [ 15] and it has an absolute magnitude of +1.42.[ 7]
Chi1 Fornacis has a stellar classification of A1 IV,[ 4] indicating that it is a slightly evolved A-type star that is ceasing hydrogen fusion at its core. Alternatively, it has been given a class of A1 Vbn,[ 16] indicating that it is instead a slightly less luminous A-type main-sequence star with broad or nebulous absorption lines due to rapid rotation. It has 2.05 times the mass of the Sun [ 8] and 2.20 times the radius of the Sun .[ 9] It radiates 31.24 times the luminosity of the Sun from its photosphere at an effective temperature of 8,870 K .[ 3] Chi1 Fornacis has a solar metallicity [ 8] and it is estimated to be only 5.5 million years old.[ 12] It spins rapidly with a projected rotational velocity of 136 km/s .[ 11]
It is the brightest star and titular member in the χ1 Fornacis cluster, a star cluster around 104 parsecs from Earth .[ 17]
χ1 Fornacis cluster
The χ1 Fornacis cluster , or Alessi 13,[ 18] is one of the four star clusters known within 110 parsecs from Earth. [ 17] Despite its closeness, the χ1 Fornacis cluster has barely been studied. Its age is 40 million years and its distance is 104 parsecs.[ 17] The χ1 Fornacis cluster appears to be closely related to the Tucana–Horologium and Columba associations .[ 17] A remarkable, unprecedented aspect of the cluster is the large percentage of M-type stars with warm excess infrared emission due to orbiting dust grains.[ 17]
References
^ a b c d e Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties" . Astronomy and Astrophysics . 674 : A1. arXiv :2208.00211 . Bibcode :2023A&A...674A...1G . doi :10.1051/0004-6361/202243940 . S2CID 244398875 .
Gaia DR3 record for this source at VizieR .
^ a b Høg, E.; Fabricius, C.; Makarov, V. V.; Urban, S.; Corbin, T.; Wycoff, G.; Bastian, U.; Schwekendiek, P.; Wicenec, A. (March 2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics . 355 : L27 – L30 . Bibcode :2000A&A...355L..27H . ISSN 0004-6361 . S2CID 17128864 .
^ a b c d Zorec, J.; Royer, F. (January 2012). "Rotational velocities of A-type stars IV: Evolution of rotational velocities" . Astronomy & Astrophysics . 537 : A120. arXiv :1201.2052 . Bibcode :2012A&A...537A.120Z . doi :10.1051/0004-6361/201117691 . eISSN 1432-0746 . ISSN 0004-6361 . S2CID 55586789 .
^ a b Houk, N. (1982). Michigan Catalogue of Two-dimensional Spectral Types for the HD stars. Declinations −40° to −26° . Vol. 3. Bibcode :1982mcts.book.....H .
^ Johnson, H. L.; Mitchell, R. I.; Iriarte, B.; Wisniewski, W. Z. (1966). "UBVRIJKL Photometry of the Bright Stars". Communications of the Lunar and Planetary Laboratory . 4 : 99– 110. Bibcode :1966CoLPL...4...99J .
^ a b Gontcharov, G. A. (November 2006). "Pulkovo Compilation of Radial Velocities for 35,495 Hipparcos stars in a common system". Astronomy Letters . 32 (11): 759– 771. arXiv :1606.08053 . Bibcode :2006AstL...32..759G . doi :10.1134/S1063773706110065 . eISSN 1562-6873 . ISSN 1063-7737 . S2CID 119231169 .
^ a b Anderson, E.; Francis, Ch. (May 2012). "XHIP: An extended hipparcos compilation". Astronomy Letters . 38 (5): 331– 346. arXiv :1108.4971 . Bibcode :2012AstL...38..331A . doi :10.1134/S1063773712050015 . eISSN 1562-6873 . ISSN 1063-7737 . S2CID 119257644 .
^ a b c d Bochanski, John J.; Faherty, Jacqueline K.; Gagné, Jonathan; Nelson, Olivia; Coker, Kristina; Smithka, Iliya; Desir, Deion; Vasquez, Chelsea (12 March 2018). "Fundamental Properties of Co-moving Stars Observed byGaia " . The Astronomical Journal . 155 (4): 149. arXiv :1801.00537 . Bibcode :2018AJ....155..149B . doi :10.3847/1538-3881/aaaebe . eISSN 1538-3881 . S2CID 119256051 .
^ a b Kervella, P.; Thévenin, F.; Di Folco, E.; Ségransan, D. (October 2004). "The angular sizes of dwarf stars and subgiants. Surface brightness relations calibrated by interferometry" . Astronomy & Astrophysics . 426 (1): 297– 307. arXiv :astro-ph/0404180 . Bibcode :2004A&A...426..297K . doi :10.1051/0004-6361:20035930 . eISSN 1432-0746 . ISSN 0004-6361 . S2CID 6077801 .
^ Stassun, Keivan G.; et al. (9 September 2019). "The Revised TESS Input Catalog and Candidate Target List" . The Astronomical Journal . 158 (4): 138. arXiv :1905.10694 . Bibcode :2019AJ....158..138S . doi :10.3847/1538-3881/ab3467 . eISSN 1538-3881 . hdl :1721.1/124721 . S2CID 166227927 .
^ a b Royer, F.; Gerbaldi, M.; Faraggiana, R.; Gómez, A. E. (January 2002). "Rotational velocities of A-type stars. I. Measurement of vsini in the southern hemisphere" . Astronomy & Astrophysics . 381 (1): 105– 121. arXiv :astro-ph/0110490 . Bibcode :2002A&A...381..105R . doi :10.1051/0004-6361:20011422 . eISSN 1432-0746 . ISSN 0004-6361 .
^ a b Ujjwal, K.; Kartha, Sreeja S.; Mathew, Blesson; Manoj, P.; Narang, Mayank (Apr 1, 2020). "Analysis of Membership Probability in Nearby Young Moving Groups with Gaia DR2" . The Astronomical Journal . 159 (4): 166. arXiv :2002.04801 . Bibcode :2020AJ....159..166U . doi :10.3847/1538-3881/ab76d6 . ISSN 0004-6256 .
^ Gould, Benjamin Apthorp (1878). "Uranometria Argentina : brillantez y posicion de las estrellas fijas, hasta la septima magnitud, comprendidas dentro de cien grados del polo austral : con atlas". Resultados del Observatorio Nacional Argentino . 1 . Bibcode :1879RNAO....1.....G .
^ "*chi01 Fornacis" . SIMBAD . Centre de données astronomiques de Strasbourg . Retrieved May 3, 2024 .
^ Gontcharov, George A.; Mosenkov, Aleksandr V. (28 September 2017). "Verifying reddening and extinction for Gaia DR1 TGAS main sequence stars" . Monthly Notices of the Royal Astronomical Society . 472 (4): 3805– 3820. arXiv :1709.01160 . Bibcode :2017MNRAS.472.3805G . doi :10.1093/mnras/stx2219 . eISSN 1365-2966 . ISSN 0035-8711 . S2CID 118879856 .
^ Paunzen, E.; Duffee, B.; Heiter, U.; Kuschnig, R.; Weiss, W. W. (July 2001). "A spectroscopic survey for λ Bootis stars" . Astronomy & Astrophysics . 373 (2): 625– 632. Bibcode :2001A&A...373..625P . doi :10.1051/0004-6361:20010630 . eISSN 1432-0746 . ISSN 0004-6361 .
^ a b c d e Zuckerman, B.; Klein, Beth; Kastner, Joel (2019). "The Nearby, Young, χ1 Fornacis Cluster: Membership, Age, and an Extraordinary Ensemble of Dusty Debris Disks" . The Astrophysical Journal . 887 (1). 87. arXiv :1909.08764 . Bibcode :2019ApJ...887...87Z . doi :10.3847/1538-4357/ab45ea .
^ P. A. B. Galli; H. Bouy; J. Olivares; N. Miret-Roig; L. M. Sarro; D. Barrado; A. Berihuete (2021). "χ1 Fornacis cluster DANCe: Census of stars, structure, and kinematics of the cluster with Gaia -EDR3" (PDF) . Astronomy and Astrophysics . 654 . A122. arXiv :2108.11208 . Bibcode :2021A&A...654A.122G . doi :10.1051/0004-6361/202141366 . Retrieved 28 November 2023 .