HD 170642

	HD 170642
Observationsdata; Epok: J2000.0
Stjärnbild	Södra kronan
Rektascension	18t 32m 21,33140s
Deklination	-39° 42′ 14,4023″
Skenbar magnitud ()	5,16 ± 0,01
Stjärntyp
Spektraltyp	A3 V eller A3 Van
B–V	+0,08
Astrometri
Radialhastighet ()	-6 ± 4,2 km/s
Egenrörelse (µ)	RA: +32,47 mas/år; Dek.: -37,47 mas/år
Parallax ()	14,23 ± 0,23
Avstånd	229 ± 4 lå (70 ± 1 pc)
Absolut magnitud ()	+0,93
Detaljer
Massa	2,25 M☉
Radie	2,59 ± 0,13 R☉
Luminositet	32,6 L☉
Temperatur	8 938 ± 161 K
Metallicitet	+0,24
Vinkelhastighet	177 ± 1 km/s
Ålder	480 miljoner år
Andra beteckningar
	13 G Coronae Australis,, HD 170642, CD-39 12696, CPD-39 8114, HIC 90887, HIP 90887, HR 6942, 2MASS J18322132-3942144, PLX 4255, PPM 297850, SAO 210277, TD1 22574, TYC 7906-1557-1, uvby98 100170642, Gaia DR2 6723805631578978816, Gaia DR3 6723805631578978816

HD 170642 eller HR 6942, är en ensam stjärna^[16] belägen i mellersta delen av stjärnbilden Södra kronan. Den har en skenbar magnitud av ca 5,16^[2] och är svagt synlig för blotta ögat där ljusföroreningar ej förekommer. Baserat på parallaxmätning inom Hipparcosuppdraget på ca 14,23 mas^[1] beräknas den befinna sig på ett avstånd av ca 229 ljusår (ca 70 parsec) från solen. Den rör sig närmare solen med en heliocentrisk radialhastighet av ca -6 km/s.^[6] Stjärnan minskas på dess nuvarande avstånd i ljusstyrka genom skymning av interstellärt stoft med 0,28 magnitud^[17] och den har en absolut magnitud på +0,93.^[7]

Egenskaper

HD 170642 är en vit till blå stjärna i huvudserien av spektralklass A3 V.^[3] Andra källor inkluderar breda/diffusa absorptionslinjer på grund av snabb rotation.^[18]^[4] Den har en massa av ca 2,3^[8] solmassor, en radie av ca 2,6^[9] solradier och utsänder energi från dess fotosfär motsvarande ca 33^[10] gånger solen vid en effektiv temperatur av ca 8 900^[11] K. Den har en järnmängd på 74 procent av solens.^[12] Liksom de flesta heta stjärnor roterar den snabbt med en projicerad rotationshastighet på 177 km/s.^[19]

Referenser

Den här artikeln är helt eller delvis baserad på material från engelskspråkiga Wikipedia, HD 170642, 14 maj 2023..

Noter

^ [a b c d e f] van Leeuwen, Floor (13 August 2007). "Validation of the new Hipparcos reduction". Astronomy & Astrophysics. 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. eISSN 1432-0746. ISSN 0004-6361. Hipparcos 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] Houk, N. (1982). Michigan Catalogue of Two-dimensional Spectral Types for the HD stars. Volume III: Declinations −40° to −26°. Bibcode:1982mcts.book.....H.
^ [a b] Gray, R. O.; Garrison, R. F. (July 1989). "The late A-type stars - Refined MK classification, confrontation with Stromgren photometry, and the effects of rotation". The Astrophysical Journal Supplement Series. 70: 623. Bibcode:1989ApJS...70..623G. doi:10.1086/191349. eISSN 1538-4365. ISSN 0067-0049.
^ Lake, R. (1965). "Photometric Magnitudes and Colours for Bright Southern Stars (Sixth List)". Monthly Notes of the Astronomical Society of South Africa. 24: 41. Bibcode:1965MNSSA..24...41L. ISSN 0024-8266.
^ [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] David, Trevor J.; Hillenbrand, Lynne A. (12 May 2015). "The Ages of Early-type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets". The Astrophysical Journal. 804 (2): 146. arXiv:1501.03154. Bibcode:2015ApJ...804..146D. doi:10.1088/0004-637X/804/2/146. eISSN 1538-4357.
^ [a b] David, Trevor J.; Hillenbrand, Lynne A. (12 May 2015). "The Ages of Early-type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets". The Astrophysical Journal. 804 (2): 146. arXiv:1501.03154. Bibcode:2015ApJ...804..146D. doi:10.1088/0004-637X/804/2/146. eISSN 1538-4357.
^ [a b] McDonald, I.; Zijlstra, A. A.; Boyer, M. L. (21 November 2012). "Fundamental parameters and infrared excesses of Hipparcos stars: Parameters and IR excesses from Hipparcos". Monthly Notices of the Royal Astronomical Society. 427 (1): 343–357. arXiv:1208.2037. Bibcode:2012MNRAS.427..343M. doi:10.1111/j.1365-2966.2012.21873.x. eISSN 1365-2966. ISSN 0035-8711.
^ [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. eISSN 1538-3881. hdl:1721.1/124721. S2CID 166227927.
^ [a b] Erspamer, D.; North, P. (28 January 2003). "Automated spectroscopic abundances of A and F-type stars using echelle spectrographs". Astronomy & Astrophysics. 398 (3): 1121–1135. arXiv:astro-ph/0210065. Bibcode:2003A&A...398.1121E. doi:10.1051/0004-6361:20021711. eISSN 1432-0746.ISSN 0004-6361.
^ [a b] 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.
^ https://simbad.cds.unistra.fr/simbad/sim-id?Ident=HR+6942. Hämtad 2024-11-02.
^ "HD 170642". SIMBAD. Centre de données astronomiques de Strasbourg. Hämtade 25 december 2022.
^ Eggleton, P. P.; Tokovinin, A. A. (11 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. eISSN 1365-2966. ISSN 0035-8711. S2CID 14878976.
^ 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.
^ Evans, D. S. (1966). "Fundamental data for Southern stars (6th list)". Royal Greenwich Observatory Bulletins. 110: 185. Bibcode:1966RGOB..110..185E.
^ Díaz, C. G.; González, J. F.; Levato, H.; Grosso, M. (July 2011). "Accurate stellar rotational velocities using the Fourier transform of the cross correlation maximum". Astronomy & Astrophysics. 531: A143. arXiv:1012.4858. Bibcode:2011A&A...531A.143D. doi:10.1051/0004-6361/201016386. eISSN 1432-0746. ISSN 0004-6361.

Externa länkar

https://www.universeguide.com/star/90887/hd170642

[A-1] [a b c d e f] van Leeuwen, Floor (13 August 2007). "Validation of the new Hipparcos reduction". Astronomy & Astrophysics. 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. eISSN 1432-0746. ISSN 0004-6361. Hipparcos record for this source at VizieR.

[B-2] [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.

[C-3] [a b] Houk, N. (1982). Michigan Catalogue of Two-dimensional Spectral Types for the HD stars. Volume III: Declinations −40° to −26°. Bibcode:1982mcts.book.....H.

[D-4] [a b] Gray, R. O.; Garrison, R. F. (July 1989). "The late A-type stars - Refined MK classification, confrontation with Stromgren photometry, and the effects of rotation". The Astrophysical Journal Supplement Series. 70: 623. Bibcode:1989ApJS...70..623G. doi:10.1086/191349. eISSN 1538-4365. ISSN 0067-0049.

[E-5] Lake, R. (1965). "Photometric Magnitudes and Colours for Bright Southern Stars (Sixth List)". Monthly Notes of the Astronomical Society of South Africa. 24: 41. Bibcode:1965MNSSA..24...41L. ISSN 0024-8266.

[F-6] [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.

[G-7] [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.

[H-8] [a b c] David, Trevor J.; Hillenbrand, Lynne A. (12 May 2015). "The Ages of Early-type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets". The Astrophysical Journal. 804 (2): 146. arXiv:1501.03154. Bibcode:2015ApJ...804..146D. doi:10.1088/0004-637X/804/2/146. eISSN 1538-4357.

[I-9] [a b] David, Trevor J.; Hillenbrand, Lynne A. (12 May 2015). "The Ages of Early-type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets". The Astrophysical Journal. 804 (2): 146. arXiv:1501.03154. Bibcode:2015ApJ...804..146D. doi:10.1088/0004-637X/804/2/146. eISSN 1538-4357.

[J-10] [a b] McDonald, I.; Zijlstra, A. A.; Boyer, M. L. (21 November 2012). "Fundamental parameters and infrared excesses of Hipparcos stars: Parameters and IR excesses from Hipparcos". Monthly Notices of the Royal Astronomical Society. 427 (1): 343–357. arXiv:1208.2037. Bibcode:2012MNRAS.427..343M. doi:10.1111/j.1365-2966.2012.21873.x. eISSN 1365-2966. ISSN 0035-8711.

[L-11] [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. eISSN 1538-3881. hdl:1721.1/124721. S2CID 166227927.

[K-12] [a b] Erspamer, D.; North, P. (28 January 2003). "Automated spectroscopic abundances of A and F-type stars using echelle spectrographs". Astronomy & Astrophysics. 398 (3): 1121–1135. arXiv:astro-ph/0210065. Bibcode:2003A&A...398.1121E. doi:10.1051/0004-6361:20021711. eISSN 1432-0746.ISSN 0004-6361.

[N-13] [a b] 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.

[SIMBAD-14] ttps://simbad.cds.unistra.fr/simbad/sim-id?Ident=HR+6942. Hämtad 2024-11-02.

[O-15] "HD 170642". SIMBAD. Centre de données astronomiques de Strasbourg. Hämtade 25 december 2022.

[P-16] Eggleton, P. P.; Tokovinin, A. A. (11 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. eISSN 1365-2966. ISSN 0035-8711. S2CID 14878976.

[Q-17] 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.

[R-18] Evans, D. S. (1966). "Fundamental data for Southern stars (6th list)". Royal Greenwich Observatory Bulletins. 110: 185. Bibcode:1966RGOB..110..185E.

[M-19] Díaz, C. G.; González, J. F.; Levato, H.; Grosso, M. (July 2011). "Accurate stellar rotational velocities using the Fourier transform of the cross correlation maximum". Astronomy & Astrophysics. 531: A143. arXiv:1012.4858. Bibcode:2011A&A...531A.143D. doi:10.1051/0004-6361/201016386. eISSN 1432-0746. ISSN 0004-6361.

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Observationsdata Epok: J2000.0
HD 170642

Stjärnbild	Södra kronan
Rektascension	18^t 32^m 21,33140^s^[1]
Deklination	-39° 42′ 14,4023″^[1]
Skenbar magnitud ( $V$ )	5,16 ± 0,01^[2]
Stjärntyp
Spektraltyp	A3 V^[3] eller A3 Van^[4]
B–V	+0,08^[5]
Astrometri
Radialhastighet ( $R_{v}$ )	-6 ± 4,2^[6] km/s
Egenrörelse (µ)	RA: +32,47^[1] mas/år Dek.: -37,47^[1] mas/år
Parallax ( $\pi$ )	14,23 ± 0,23^[1]
Avstånd	229 ± 4 lå (70 ± 1 pc)
Absolut magnitud ( $M_{V}$ )	+0,93^[7]
Detaljer
Massa	2,25^[8] M_☉
Radie	2,59 ± 0,13^[9] R_☉
Luminositet	32,6^[10] L_☉
Temperatur	8 938 ± 161^[11] K
Metallicitet	+0,24^[12]
Vinkelhastighet	177 ± 1^[13] km/s
Ålder	480^[8] miljoner år
Andra beteckningar
13 G Coronae Australis,^[13], HD 170642, CD-39 12696, CPD-39 8114, HIC 90887, HIP 90887, HR 6942, 2MASS J18322132-3942144, PLX 4255, PPM 297850, SAO 210277, TD1 22574, TYC 7906-1557-1, uvby98 100170642, Gaia DR2 6723805631578978816, Gaia DR3 6723805631578978816^[14]^[15]