RX Telescopii
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Telescopium |
| Right ascension | 19h 06m 58.206s[2] |
| Declination | −45° 58′ 13.54″[2] |
| Apparent magnitude (V) | 6.45 - 7.47[3] |
| Characteristics | |
| Evolutionary stage | Red supergiant |
| Spectral type | M3Iab[3] |
| Variable type | LC[4] |
| Astrometry | |
| Radial velocity (Rv) | 19.87±0.64[5] km/s |
| Proper motion (μ) | RA: 2.285±0.092[5] mas/yr Dec.: -6.520[5] mas/yr |
| Parallax (π) | 0.4914 ± 0.0810 mas[5] |
| Distance | 2,753 ly (844.6156 pc)[2] |
| Details | |
| Mass | 25-35[6] M☉ |
| Radius | 339[a] R☉ |
| Luminosity | 340,000 L☉ |
| Temperature | 3,757.8[2] K |
| Other designations | |
| Database references | |
| SIMBAD | data |
RX Telescopii is an irregular variable star in the constellation Telescopium. It has a maximum magnitude of 6.45 and a minimum magnitude 7.47. It is a red supergiant with a spectral type of M3Iab, indicating the star is an intermediate-size luminous supergiant star.[3]
The distance to RX Telescopii is uncertain. It has a Gaia Data Release 2 parallax of 0.1699±0.0790 mas,[9] suggesting a distance around 6,000 parsecs.[9] A more rigorous statistical calculation gives a distance of 4,726+2,371
−1,315 pc,[10] suggesting a radius of 1,897 R☉ using an angular diameter of 3.734 mas, which would make it one of the largest stars discovered and its photosphere engulf the orbit of Jupiter, and nearing that of Saturn if it was placed in the Solar System.[7] However the Gaia database has an astrometric noise value larger than the parallax itself and about ten times larger than the typical maximum for a reliable parallax, thus this distance, hence the radius, are inaccurate.[9] Gaia DR3 published a distance of 844.6 pc (2,755 ly),[2], corresponding to a much smaller radius of 339 R☉ using the angular diameter.
Notes[edit]
- ^ From an angular diameter of 3.734 milliarcseconds [7] and a distance of 844.6156 parsecs.[2]
References[edit]
- ^ "ASAS All Star Catalogue". The All Sky Automated Survey. Retrieved 8 December 2021.
- ^ a b c d e f 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 BSJ (11 November 2011). "RX Telescopii". AAVSO Website. American Association of Variable Star Observers. Retrieved 26 June 2014.
- ^ Samus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S. 1: B/gcvs. Bibcode:2009yCat....102025S.
- ^ a b c d 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.
- ^ Wright, Candace O.; Egan, Michael P.; Kraemer, Kathleen E.; Price, Stephan D. (2003). "The Tycho-2 Spectral Type Catalog". The Astronomical Journal. 125 (1): 359. Bibcode:2003AJ....125..359W. doi:10.1086/345511. S2CID 122781581.
- ^ a b Cruzalèbes, P.; Petrov, R. G.; Robbe-Dubois, S.; Varga, J.; Burtscher, L.; Allouche, F.; Berio, P.; Hofmann, K. H.; Hron, J.; Jaffe, W.; Lagarde, S.; Lopez, B.; Matter, A.; Meilland, A.; Meisenheimer, K.; Millour, F.; Schertl, D. (2019). "A catalogue of stellar diameters and fluxes for mid-infrared interferometry". Monthly Notices of the Royal Astronomical Society. 490 (3): 3158–3176. arXiv:1910.00542. Bibcode:2019MNRAS.490.3158C. doi:10.1093/mnras/stz2803. S2CID 203610229.
- ^ "V* RX Tel". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 26 June 2020.
- ^ a b c 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.
- ^ Bailer-Jones, C. A. L.; Rybizki, J.; Fouesneau, M.; Mantelet, G.; Andrae, R. (2018). "Estimating Distance from Parallaxes. IV. Distances to 1.33 Billion Stars in Gaia Data Release 2". The Astronomical Journal. 156 (2): 58. arXiv:1804.10121. Bibcode:2018AJ....156...58B. doi:10.3847/1538-3881/aacb21. S2CID 119289017.
