RSGC1-F01

RSGC1-F01
RSGC1-F01 (circled in red) located near the center of the RSGC1 cluster
Observation data
Epoch J2000      Equinox J2000
Constellation Scutum
Right ascension 18h 37m 56.31s[1]
Declination −06° 52′ 32.2″[1]
Characteristics
Evolutionary stage Red supergiant[2]
Spectral type M3I[3]
Apparent magnitude (J) 9.748[4]
Apparent magnitude (H) 6.587[4]
Astrometry
Radial velocity (Rv)107.2[3] km/s
Proper motion (μ) RA: −4.569 mas/yr[1]
Dec.: −5.074 mas/yr[1]
Parallax (π)0.9176±0.5816 mas[1]
Distance22,000±2,900 ly
Details
Radius1,530+330
−424
[2][a] R
Luminosity335,000±160,000[2] – 380,000[5] L
Temperature3,550[2] K
Other designations
RSGC1-F01, [FMR2006] 1, TIC 6841341, 2MASS J18375629-0652322[3]
Database references
SIMBADdata

RSGC1-F01 is a red supergiant star in the young open cluster RSGC1 located in the constellation of Scutum. It is one of the largest stars discovered so far and also one of the most luminous cool supergiants, with a radius around 1,530 solar radii (1.06×109 km; 7.1 au) and around 300,000 solar luminosities, with the former corresponding to a volume 3.58 billion times bigger than the Sun.[2][a] If placed at the center of the Solar System, the photosphere would engulf the orbit of Jupiter.

The star is heavily obscured by interstellar dust and is invisible in optical wavelengths; it has only been studied through infrared and submillimeter observations.[6] RSGC1 itself was discovered in 2006 using data from infrared surveys.[7]

Observation

RSGC1-F01 is a member of the open cluster RSGC1, which is estimated to be 10–14 million years old with a total mass of about 30,000 solar masses (M). All red supergiants in RSGC1 share similar initial masses (around 25 M), making the cluster a valuable for studying the evolution and mass loss of massive stars.[8]

ALMA observations in 2024 detected CO rotational line emission from RSGC1-F01 and several other cluster members, allowing direct measurement of gas mass-loss rates and wind velocities.[8] The wind speed for RSGC1-F01 (along with F02, F03, and F04) is 11±3 km/s.[8] These data have contributed to a new mass-loss rate prescription for M-type supergiants with effective temperatures between roughly 3,200 and 3,800 K, showing that CO-derived rates are systematically lower than dust-based estimates.[8]

See also

Notes

  1. ^ a b Calculated, using the Stefan-Boltzmann law and the star's effective temperature and luminosity, with respect to the solar nominal effective temperature of 5,772 K:

References

  1. ^ a b c d 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.
  2. ^ a b c d e f Humphreys, Roberta M.; Helmel, Greta; Jones, Terry J.; Gordon, Michael S. (2020). "Exploring the Mass Loss Histories of the Red Supergiants". The Astronomical Journal. 160 (3): 145. arXiv:2008.01108. Bibcode:2020AJ....160..145H. doi:10.3847/1538-3881/abab15. S2CID 220961677.
  3. ^ a b c "[FMR2006] 1". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2025-12-17.
  4. ^ a b Davies, Ben; Figer, Don F.; Law, Casey J.; Kudritzki, Rolf-Peter; Najarro, Francisco; Herrero, Artemio; MacKenty, John W. (2008). "The cool supergiant population of the massive young star cluster RSGC1". The Astrophysical Journal. 676 (2): 1016–1028. arXiv:0711.4757. Bibcode:2008ApJ...676.1016D. doi:10.1086/527350. ISSN 0004-637X.
  5. ^ Emma Bensor (2020). "A new mass-loss rate prescription for red supergiants". Monthly Notices of the Royal Astronomical Society. 492 (4): 5994–6006. arXiv:2001.07222. Bibcode:2020MNRAS.492.5994B. doi:10.1093/mnras/staa255. S2CID 210839222.
  6. ^ admin (2025-08-29). "RSGC1-F01 | Star Facts". Retrieved 2026-01-22.
  7. ^ Figer, Donald F.; MacKenty, John W.; Robberto, Massimo; Smith, Kester; Najarro, Francisco; Kudritzki, Rolf P.; Herrero, Artemio (June 2006). "Discovery of an Extraordinarily Massive Cluster of Red Supergiants". The Astrophysical Journal. 643 (2): 1166–1179. arXiv:astro-ph/0602146. Bibcode:2006ApJ...643.1166F. doi:10.1086/503275. ISSN 0004-637X.
  8. ^ a b c d Decin, Leen; Richards, Anita M. S.; Marchant, Pablo; Sana, Hugues (2024). "ALMA detection of CO rotational line emission in red supergiant stars of the massive young star cluster RSGC1". Astronomy & Astrophysics. 681: A17. arXiv:2303.09385. doi:10.1051/0004-6361/202244635.