HD 200044
M-type star in the constellation Delphinus
HD 200044 (HR 8044 ) is a solitary[ 13] star in the equatorial constellation Delphinus . It has an apparent magnitude of 5.7,[ 2] allowing it to be faintly seen with the naked eye . The object is located 598 light years away,[ 1] but is approaching the Solar System with a heliocentric radial velocity of −15.07 km/s .[ 7]
HD 200044 has a spectral classification of M3 IIIab,[ 4] indicating that its an ageing red giant . It is currently on the asymptotic giant branch and is fusing hydrogen and helium in shells around an inert carbon core.[ 3] As a consequence, it has expanded to 58 times the radius of the Sun and is now radiating with a luminosity over 500 times greater than that of the Sun . HD 200044's large size and high luminosity yield an effective temperature of 3,707 K , giving it a red glow. HD 200044 is suspected to be a variable star with an amplitude of 0.05 magnitudes.[ 6]
There is a 10th magnitude optical companion separated 49.3″ away and at a position angle of 337° as of 2014. However, the separation is increasing due to HD 200044's high proper motion.[ 14]
References
^ a b c d e Brown, A. G. A. ; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties" . Astronomy & Astrophysics . 649 : A1. arXiv :2012.01533 . Bibcode :2021A&A...649A...1G . doi :10.1051/0004-6361/202039657 . S2CID 227254300 . (Erratum: doi :10.1051/0004-6361/202039657e ) . Gaia EDR3 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 .
^ a b Eggen, Olin J. (July 1992). "Asymptotic giant branch stars near the sun" . The Astronomical Journal . 104 : 275. Bibcode :1992AJ....104..275E . doi :10.1086/116239 . ISSN 0004-6256 .
^ a b Yamashita, Y. (1967). "MK Spectral Types of Bright M-Type Stars". Publications of the Dominion Astrophysical Observatory Victoria . 13 : 44. Bibcode :1967PDAO...13...47Y . ISSN 0078-6950 .
^ Haggkvist, L.; Oja, T. (1970). "Results of BV photometry 1969-70 (Uppsala refractor)". Private Communication . Bibcode :1970Priv.........0H .
^ a b Samus’, N. N.; Kazarovets, E. V.; Durlevich, O. V.; Kireeva, N. N.; Pastukhova, E. N. (January 2017). "General catalogue of variable stars: Version GCVS 5.1". Astronomy Reports . 61 (1): 80–88. Bibcode :2017ARep...61...80S . doi :10.1134/S1063772917010085 . eISSN 1562-6881 . ISSN 1063-7729 . S2CID 255195566 .
^ a b Famaey, B.; Pourbaix, D.; Frankowski, A.; Van Eck, S.; Mayor, M.; Udry, S.; Jorissen, A. (18 February 2009). "Spectroscopic binaries among Hipparcos M giants" . Astronomy & Astrophysics . 498 (2): 627–640. arXiv :0901.0934 . Bibcode :2009A&A...498..627F . doi :10.1051/0004-6361/200810698 . eISSN 1432-0746 . ISSN 0004-6361 .
^ 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 . ISSN 1063-7737 . S2CID 255204555 .
^ Kervella, Pierre; Arenou, Frédéric; Thévenin, Frédéric (2022). "Stellar and substellar companions from Gaia EDR3. Proper-motion anomaly and resolved common proper-motion pairs". Astronomy and Astrophysics . 657 : 657. arXiv :2109.10912 . Bibcode :2022A&A...657A...7K . doi :10.1051/0004-6361/202142146 . S2CID 237605138 .
^ a b 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 . ISSN 0004-6256 .
^ Brown, A. G. A. ; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties" . Astronomy & Astrophysics . 616 . A1. arXiv :1804.09365 . Bibcode :2018A&A...616A...1G . doi :10.1051/0004-6361/201833051 . Gaia DR2 record for this source at VizieR .
^ McDonald, I.; Zijlstra, A. A.; Watson, R. A. (2017). "Fundamental parameters and infrared excesses of Tycho-Gaia stars" . Monthly Notices of the Royal Astronomical Society . 471 (1): 770. arXiv :1706.02208 . Bibcode :2017MNRAS.471..770M . doi :10.1093/mnras/stx1433 .
^ Eggleton, P. P.; Tokovinin, A. A. (September 2008). "A catalogue of multiplicity among bright stellar systems" . Monthly Notices of the Royal Astronomical Society . 389 (2): 869–879. arXiv :0806.2878 . Bibcode :2008MNRAS.389..869E . doi :10.1111/j.1365-2966.2008.13596.x . S2CID 14878976 .
^ Mason, Brian D.; Wycoff, Gary L.; Hartkopf, William I.; Douglass, Geoffrey G.; Worley, Charles E. (December 2001). "The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog" . The Astronomical Journal . 122 (6): 3466–3471. Bibcode :2001AJ....122.3466M . doi :10.1086/323920 . ISSN 0004-6256 .