| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Sculptor[1] |
| Right ascension | 01h 26m 58.09462s[2] |
| Declination | −32° 32′ 35.4377″[2] |
| Apparent magnitude (V) | +5.5 - 8.0[3] |
| Characteristics | |
| Evolutionary stage | AGB[4] |
| Spectral type | C6,5ea(Np)[5] |
| U−B color index | +7.67[6] |
| B−V color index | +3.87[6] |
| Variable type | SRb[7] |
| Astrometry | |
| Radial velocity (Rv) | −5.40[8] km/s |
| Proper motion (μ) | RA: −9.784[2] mas/yr Dec.: −30.900[2] mas/yr |
| Parallax (π) | 2.2724±0.1471 mas[2] |
| Distance | 1,180±140 ly (361±44 pc)[9] |
| Absolute magnitude (MV) | −0.45[1] |
| Details | |
| Mass | 1.3±0.7 [10] M☉ |
| Radius | 411±43[11] R☉ |
| Luminosity | 8,000±1,000[11] L☉ |
| Surface gravity (log g) | −0.5±0.1[11] cgs |
| Temperature | 2640±80 [10] K |
| Metallicity [Fe/H] | 0.0[5] dex |
| Other designations | |
| R Scl, CD−33°525, HD 8879, HIP 6759, HR 423, SAO 193122, WDS J01270-3233A, AAVSO 0122-33[12] | |
| Database references | |
| SIMBAD | data |
R Sculptoris is a variable star system in the southern constellation of Sculptor.[13][14] Parallax measurements provide a distance estimate of approximately 1,435 ± 98 light-years from the Sun.[2] An independent estimate based on measurements of an ejected shell surrounding the star yield a distance of 1,180 ± 140 light-years.[9] The star is drifting closer with a radial velocity of −5.4 km/s.[8]
Benjamin Apthorp Gould discovered that the star's brightness varies, in 1872. It was listed with its variable star designation, R Sculptoris, in Annie Jump Cannon's 1907 work Second Catalog of Variable Stars.[15] Both AAVSO and ASAS data shows that R Sculptoris is occasionally brighter than 6th magnitude, and faintly visible to the naked eye under excellent observing conditions.[16][17]
This is an aging giant star on the asymptotic giant branch with a stellar classification of C6,5ea(Np),[5] which indicates a carbon-rich atmosphere. It is a semi-regular pulsating star of the SRb[7] type that is nearing the end of its fusing lifespan. A sine curve fitted to the last ten pulsation cycles prior to 2017 give a pulsation period of 376 days with an amplitude of 0.75 magnitude. The star is shedding its outer atmosphere, and it is surrounded by a thin shell of dust and gas that was created during the most recent thermal pulse around 2,000 years ago.[9]
Observations have revealed a spiral structure in the material around the star.[19] The spiral is suspected to be caused by an unseen companion star.[13] The spiral windings are consistent with an orbital period of ~350 years.[19]
Gallery
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This image captures approximately 20x20 milliarcseconds.[20]
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Spiral spotted by ALMA around the star (data visualisation).
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R Sculptoris and its hidden companion, taken by Hubble Space Telescope
![👁 This image captures approximately 20x20 milliarcseconds.[20]](https://upload.wikimedia.org/wikipedia/commons/thumb/2/2b/R_Sculptoris_A_red_giant_sheds_its_skin.jpg/120px-R_Sculptoris_A_red_giant_sheds_its_skin.jpg){kind=link}
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References
[edit]- ^ a b 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. XHIP record for this object at VizieR.
- ^ a b c d e f 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.
- ^ "R Scl". International Variable Star Index. AAVSO. Retrieved 2026-01-14.
- ^ Maercker, M.; De Beck, E.; Khouri, T.; Vlemmings, W. H. T.; Gustafsson, J.; Olofsson, H.; Tafoya, D.; Kerschbaum, F.; Lindqvist, M. (2024). "Probing the dynamical and kinematical structures of detached shells around AGB stars". Astronomy and Astrophysics. 687: A112. arXiv:2405.01222. Bibcode:2024A&A...687A.112M. doi:10.1051/0004-6361/202449643.
- ^ a b c Cruzalèbes, P.; et al. (2013). "Fundamental parameters of 16 late-type stars derived from their angular diameter measured with VLTI/AMBER". Monthly Notices of the Royal Astronomical Society. 434 (1): 437. arXiv:1306.3288. Bibcode:2013MNRAS.434..437C. doi:10.1093/mnras/stt1037. S2CID 49573767.
- ^ a b Ducati, J. R. (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system". CDS/ADC Collection of Electronic Catalogues. 2237. Bibcode:2002yCat.2237....0D.
- ^ a b Samus, N. N.; et al. (2009). "General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S. 1. Bibcode:2009yCat....102025S.
- ^ a b Gontcharov, G. A. (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. S2CID 119231169.
- ^ a b c Maercker, M.; et al. (April 2018). "An independent distance estimate to the AGB star R Sculptoris". Astronomy & Astrophysics. 611: 8. arXiv:1711.09676. Bibcode:2018A&A...611A.102M. doi:10.1051/0004-6361/201732057. S2CID 56318815. A102.
- ^ a b Wittkowski, M; et al. (2017). "Aperture synthesis imaging of the carbon AGB star R Sculptoris. Detection of a complex structure and a dominating spot on the stellar disk". Astronomy & Astrophysics. 601: A3. arXiv:1702.02574. Bibcode:2017A&A...601A...3W. doi:10.1051/0004-6361/201630214. S2CID 56160169.
- ^ a b c Drevon, J.; Millour, F.; Cruzalèbes, P.; Paladini, C.; Hron, J.; Meilland, A.; Allouche, F.; Hofmann, K.-H.; Lagarde, S.; Lopez, B.; Matter, A.; Petrov, R.; Robbe-Dubois, S.; Schertl, D.; Scicluna, P. (2022-09-01). "Locating dust and molecules in the inner circumstellar environment of R Sculptoris with MATISSE". Astronomy & Astrophysics. 665: A32. arXiv:2208.10845. Bibcode:2022A&A...665A..32D. doi:10.1051/0004-6361/202141609. ISSN 0004-6361.
- ^ "R Scl". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2020-12-06.
- ^ a b "Hubble Gazes at R Sculptoris and its Hidden Companion". SpaceDaily. 11 January 2015.
- ^ "Curious spiral spotted by ALMA around red giant star R Sculptoris (data visualisation)". Image Archive. ESO. Retrieved 11 October 2012.
- ^ Cannon, Annie J. (1907). "Second catalogue of variable stars". Annals of Harvard College Observatory. 55: 1–94. Bibcode:1907AnHar..55....1C.
- ^ "Plot a light curve". American Association of Variable Star Observers. Retrieved 16 December 2024.
- ^ "ASAS All Star Catalogue". University of Warsaw. Retrieved 16 December 2024.
- ^ "ASAS All Star Catalogue". The All Sky Automated Survey. Retrieved 8 December 2021.
- ^ a b Maercker, M.; et al. (2012). "Unexpectedly large mass loss during the thermal pulse cycle of the red giant star R Sculptoris". Nature. 490 (7419): 232–4. arXiv:1210.3030. Bibcode:2012Natur.490..232M. doi:10.1038/nature11511. PMID 23060194. S2CID 4417744.
- ^ "A red giant sheds its skin". www.eso.org. Retrieved 12 February 2018.
Further reading
[edit]- Nola Taylor Redd (October 11, 2012). "Strange Star Spiral Offers Clues to Sun's Fate". SPACE.com. Scientific American. Retrieved 31 October 2012.
