| Observation data Epoch J2000.0 Equinox J2000.0 ( ICRS) | |
|---|---|
| Constellation | Serpens |
| Right ascension | 15h 36m 28.1827s [2] |
| Declination | +15° 06′ 05.240″ [2] |
| Apparent magnitude (V) | 5.89 to 7.07 [3] |
| Characteristics | |
| Spectral type | M5IIIa [4] |
| B−V color index | 1.2 [5] |
| Variable type | SRB [3] |
| Astrometry | |
| Radial velocity (Rv) | −26±5 [5] km/s |
| Proper motion (μ) |
RA: −3.623
[2]
mas/
yr Dec.: +4.476 [2] mas/ yr |
| Parallax (π) | 4.5628 ± 0.2728 mas [2] |
| Distance | 710 ± 40
ly (220 ± 10 pc) |
| Absolute magnitude (MV) | −0.03 [6] |
| Details | |
| Mass | 3.9 [7] M☉ |
| Radius | 239 [8] R☉ |
| Luminosity | 4,969 [8] L☉ |
| Surface gravity (log g) | −0.14 [7] cgs |
| Temperature | 3,178 [7] K |
| Metallicity [Fe/H] | +0.21 [7] dex |
| Other designations | |
| Database references | |
| SIMBAD | data |
Tau4 Serpentis, Latinized from τ4 Serpentis, is a variable M-type giant star in the constellation of Serpens, approximately 710 light-years from the Earth. [5]
With a spectral classification M5IIIa, Tau4 Serpentis is a cool red giant star. The spectrum varies, [4] and some sources classify it between M4IIIe and M6IIIe. [9] Some of its spectral lines show an inverse P Cygni profile, [10] where cold infalling gas on to the star creates redshifted hydrogen absorption lines next to the normal emission lines. [11] It is classified as a semiregular late-type variable, and its magnitude varies between +5.89 and +7.07 with a period of approximately 100 days. [3]
τ4 is unique among the stars with the Bayer designation τ Serpentis as being the only one with no HR catalog number.
- ^ "ASAS-SN Variable Stars Database". ASAS-SN Variable Stars Database. ASAS-SN. Retrieved 6 January 2022.
- ^ 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 c tau 4 Ser, database entry, The combined table of GCVS Vols I-III and NL 67-78 with improved coordinates, General Catalogue of Variable Stars Archived 2017-06-20 at the Wayback Machine, Sternberg Astronomical Institute, Moscow, Russia. Accessed on line September 19, 2008.
- ^ a b Keenan, Philip C.; McNeil, Raymond C. (1989). "The Perkins catalog of revised MK types for the cooler stars". Astrophysical Journal Supplement Series. 71: 245. Bibcode: 1989ApJS...71..245K. doi: 10.1086/191373. S2CID 123149047.
- ^ a b c d V* tau04 Ser -- Pulsating variable Star, database entry, SIMBAD. Accessed on line September 19, 2008.
- ^ Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv: 1108.4971, Bibcode: 2012AstL...38..331A, doi: 10.1134/S1063773712050015, S2CID 119257644.
- ^ a b c d Anders, F.; et al. (August 2019). "Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia DR2 stars brighter than G = 18". Astronomy & Astrophysics. 628: A94. arXiv: 1904.11302. Bibcode: 2019A&A...628A..94A. doi: 10.1051/0004-6361/201935765. ISSN 0004-6361.
- ^ a b 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. S2CID 73594365.
- ^ Skiff, B. A. (2014). "VizieR Online Data Catalog: Catalogue of Stellar Spectral Classifications (Skiff, 2009-2016)". VizieR On-line Data Catalog: B/Mk. Originally Published in: Lowell Observatory (October 2014). 1. Bibcode: 2014yCat....1.2023S.
- ^ Kolotilov, E. A.; Russev, R. M. (January 1980). "Inverse P Cyg Profile of Halpha in the Spectrum of the Red Giant HD 139216 = tau4 Ser". Information Bulletin on Variable Stars. 1730: 1. Bibcode: 1980IBVS.1730....1K.
- ^ Galactic Star and Planet Formation Research Group. "Lecture 7: The Collapse of Cores and Infall" (PDF). Department of Physics and Astronomy, University of Toledo. Retrieved 17 July 2015.
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| Observation data Epoch J2000.0 Equinox J2000.0 ( ICRS) | |
|---|---|
| Constellation | Serpens |
| Right ascension | 15h 36m 28.1827s [2] |
| Declination | +15° 06′ 05.240″ [2] |
| Apparent magnitude (V) | 5.89 to 7.07 [3] |
| Characteristics | |
| Spectral type | M5IIIa [4] |
| B−V color index | 1.2 [5] |
| Variable type | SRB [3] |
| Astrometry | |
| Radial velocity (Rv) | −26±5 [5] km/s |
| Proper motion (μ) |
RA: −3.623
[2]
mas/
yr Dec.: +4.476 [2] mas/ yr |
| Parallax (π) | 4.5628 ± 0.2728 mas [2] |
| Distance | 710 ± 40
ly (220 ± 10 pc) |
| Absolute magnitude (MV) | −0.03 [6] |
| Details | |
| Mass | 3.9 [7] M☉ |
| Radius | 239 [8] R☉ |
| Luminosity | 4,969 [8] L☉ |
| Surface gravity (log g) | −0.14 [7] cgs |
| Temperature | 3,178 [7] K |
| Metallicity [Fe/H] | +0.21 [7] dex |
| Other designations | |
| Database references | |
| SIMBAD | data |
Tau4 Serpentis, Latinized from τ4 Serpentis, is a variable M-type giant star in the constellation of Serpens, approximately 710 light-years from the Earth. [5]
With a spectral classification M5IIIa, Tau4 Serpentis is a cool red giant star. The spectrum varies, [4] and some sources classify it between M4IIIe and M6IIIe. [9] Some of its spectral lines show an inverse P Cygni profile, [10] where cold infalling gas on to the star creates redshifted hydrogen absorption lines next to the normal emission lines. [11] It is classified as a semiregular late-type variable, and its magnitude varies between +5.89 and +7.07 with a period of approximately 100 days. [3]
τ4 is unique among the stars with the Bayer designation τ Serpentis as being the only one with no HR catalog number.
- ^ "ASAS-SN Variable Stars Database". ASAS-SN Variable Stars Database. ASAS-SN. Retrieved 6 January 2022.
- ^ 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 c tau 4 Ser, database entry, The combined table of GCVS Vols I-III and NL 67-78 with improved coordinates, General Catalogue of Variable Stars Archived 2017-06-20 at the Wayback Machine, Sternberg Astronomical Institute, Moscow, Russia. Accessed on line September 19, 2008.
- ^ a b Keenan, Philip C.; McNeil, Raymond C. (1989). "The Perkins catalog of revised MK types for the cooler stars". Astrophysical Journal Supplement Series. 71: 245. Bibcode: 1989ApJS...71..245K. doi: 10.1086/191373. S2CID 123149047.
- ^ a b c d V* tau04 Ser -- Pulsating variable Star, database entry, SIMBAD. Accessed on line September 19, 2008.
- ^ Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv: 1108.4971, Bibcode: 2012AstL...38..331A, doi: 10.1134/S1063773712050015, S2CID 119257644.
- ^ a b c d Anders, F.; et al. (August 2019). "Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia DR2 stars brighter than G = 18". Astronomy & Astrophysics. 628: A94. arXiv: 1904.11302. Bibcode: 2019A&A...628A..94A. doi: 10.1051/0004-6361/201935765. ISSN 0004-6361.
- ^ a b 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. S2CID 73594365.
- ^ Skiff, B. A. (2014). "VizieR Online Data Catalog: Catalogue of Stellar Spectral Classifications (Skiff, 2009-2016)". VizieR On-line Data Catalog: B/Mk. Originally Published in: Lowell Observatory (October 2014). 1. Bibcode: 2014yCat....1.2023S.
- ^ Kolotilov, E. A.; Russev, R. M. (January 1980). "Inverse P Cyg Profile of Halpha in the Spectrum of the Red Giant HD 139216 = tau4 Ser". Information Bulletin on Variable Stars. 1730: 1. Bibcode: 1980IBVS.1730....1K.
- ^ Galactic Star and Planet Formation Research Group. "Lecture 7: The Collapse of Cores and Infall" (PDF). Department of Physics and Astronomy, University of Toledo. Retrieved 17 July 2015.
| Stars |
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|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
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|
Star clusters |
| ||||||||||||
| Nebulae |
| ||||||||||||
| Galaxies |
| ||||||||||||
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