Astronomy:Rho Aquarii
| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Aquarius[1] |
| Right ascension | 22h 20m 11.917s[2] |
| Declination | −07° 49′ 15.97″[2] |
| Apparent magnitude (V) | +5.34[3] |
| Characteristics | |
| Spectral type | B8 IIIp Mn:Hg:[4] |
| U−B color index | −0.358[3] |
| B−V color index | −0.057[3] |
| Astrometry | |
| Radial velocity (Rv) | −9[5] km/s |
| Proper motion (μ) | RA: +14.803[2] mas/yr Dec.: +0.472[2] mas/yr |
| Parallax (π) | 4.3443 ± 0.1468[2] mas |
| Distance | 750 ± 30 ly (230 ± 8 pc) |
| Absolute magnitude (MV) | −1.78[1] |
| Orbit[6] | |
| Period (P) | 220.41±0.10 d |
| Eccentricity (e) | 0 (assumed) |
| Periastron epoch (T) | 2418548.7±7.4 JD |
| Semi-amplitude (K1) (primary) | 18.66±2.75 km/s |
| Details | |
| A | |
| Mass | 4.63±0.25[7] M☉ |
| Radius | 5.5[8] R☉ |
| Luminosity | 1,023+357−264[7] L☉ |
| Surface gravity (log g) | 3.5[8] cgs |
| Temperature | 12,454±152[7] K |
| Metallicity [Fe/H] | 0.059[8] dex |
| Rotation | 6.5633±0.0063 d[7] |
| Rotational velocity (v sin i) | 65.0±6.9[7] km/s |
| Other designations | |
| Database references | |
| SIMBAD | data |
Rho Aquarii is a binary star[10] system in the equatorial constellation of Aquarius. Its name is a Bayer designation that is Latinized from ρ Aquarii, and abbreviated Rho Aqr or ρ Aqr. This system is visible to the naked eye as a point of light with an apparent visual magnitude of +5.34.[3] Based upon parallax measurements, this star is located at a distance of approximately 750 light-years (230 parsecs) from the Sun.[2] It is drifting closer with a radial velocity of –9 km/s.[5] The position of this star near the ecliptic means it is subject to lunar occultations.[11]
This is a single-lined spectroscopic binary, with the presence of a companion being revealed by Doppler shifts in the spectrum.[10] An initial orbital solution for the data gives a period of 220.4 days with a circular orbit.[6]
The primary is a non-magnetic chemically peculiar star with a stellar classification of B8 IIIp Mn:Hg:.[4] It is a candidate mercury-manganese star, showing a surfeit of these elements in the spectrum.[10] At least two pulsation periods have been detected; the first is characteristic of a Delta Scuti variable and the second of a Gamma Doradus variable, suggesting this is a hybrid pulsator.[7] The dominant pulsation period is 1.1203±0.0002 d.[12] With 4.63 times the Sun's mass, this star is radiating 1,023 times as much luminosity from its outer atmosphere at an effective temperature of 12,454 K.[7] This heat gives it the blue-white hue of a B-type star.[13] It is spinning with a rotation period of 6.5633±0.0063 d.[7] The primary does not display photometric variability, but the companion may be a variable star.[14] Although no specific age estimates have been published for this star, it is likely to be less than 50 million years old.[15]
References
- ↑ 1.0 1.1 Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters 38 (5): 331, doi:10.1134/S1063773712050015, Bibcode: 2012AstL...38..331A.
- ↑ 2.0 2.1 2.2 2.3 2.4 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940 Gaia DR3 record for this source at VizieR.
- ↑ 3.0 3.1 3.2 3.3 Cousins, A. W. J. (1984), "Standardization of Broadband Photometry of Equatorial Standards", South African Astronomical Observatory Circulars 8: 59, Bibcode: 1984SAAOC...8...59C.
- ↑ 4.0 4.1 Abt, Helmut A.; Levato, Hugo; Grosso, Monica (July 2002), "Rotational Velocities of B Stars", The Astrophysical Journal 573 (1): 359–365, doi:10.1086/340590, Bibcode: 2002ApJ...573..359A.
- ↑ 5.0 5.1 Wilson, Ralph Elmer (1953), "General Catalogue of Stellar Radial Velocities", Carnegie Institute Washington D.C. Publication (Washington: Carnegie Institution of Washington), Bibcode: 1953GCRV..C......0W.
- ↑ 6.0 6.1 Stickland, D. J.; Weatherby, J. (July 1984), "Radial velocities of northern mercury stars", Astronomy and Astrophysics, Supplemental Series 57: 55–67, Bibcode: 1984A&AS...57...55S.
- ↑ 7.0 7.1 7.2 7.3 7.4 7.5 7.6 7.7 Paunzen, E. et al. (February 2013), "A photometric study of chemically peculiar stars with the STEREO satellites - II. Non-magnetic chemically peculiar stars", Monthly Notices of the Royal Astronomical Society 429 (1): 119–125, doi:10.1093/mnras/sts318, Bibcode: 2013MNRAS.429..119P.
- ↑ 8.0 8.1 8.2 Huber, Daniel; Bryson, Stephen T.; Haas, Michael R.; Barclay, Thomas; Barentsen, Geert; Howell, Steve B.; Sharma, Sanjib; Stello, Dennis et al. (2016), "The K2 Ecliptic Plane Input Catalog (EPIC) and Stellar Classifications of 138,600 Targets in Campaigns 1-8", The Astrophysical Journal Supplement Series 224 (1): 2, doi:10.3847/0067-0049/224/1/2, Bibcode: 2016ApJS..224....2H.
- ↑ "* rho Aqr". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=%2A+rho+Aqr.
- ↑ 10.0 10.1 10.2 Makaganiuk, V. et al. (January 2011), "The search for magnetic fields in mercury-manganese stars", Astronomy and Astrophysics 525: A97, doi:10.1051/0004-6361/201015666, Bibcode: 2011A&A...525A..97M.
- ↑ Hilaire, G. (March 1974), "Observations of occultations of stars by the moon", Astronomy and Astrophysics Supplement 13: 395, Bibcode: 1974A&AS...13..395H. See the SAO 146023 entry on p. 402.
- ↑ Bowman, D. M. et al. (August 2018), "K2 space photometry reveals rotational modulation and stellar pulsations in chemically peculiar A and B stars", Astronomy & Astrophysics 616: id. A77, doi:10.1051/0004-6361/201833037, Bibcode: 2018A&A...616A..77B.
- ↑ "The Colour of Stars", Australia Telescope, Outreach and Education (Commonwealth Scientific and Industrial Research Organisation), December 21, 2004, http://outreach.atnf.csiro.au/education/senior/astrophysics/photometry_colour.html, retrieved 2012-01-16
- ↑ Adelman, S. J.; Young, K. J. (January 2005), "uvby FCAPT photometry of the mCP stars HR 2258, MW Vul, and HR 9017 and the HgMn star 46 ρ Aqr", Astronomy and Astrophysics 429: 317–322, doi:10.1051/0004-6361:20041118, Bibcode: 2005A&A...429..317A.
- ↑ Kerr, Ronan M. P.; Rizzuto, Aaron C.; Kraus, Adam L.; Offner, Stella S. R. (2021), "Stars with Photometrically Young Gaia Luminosities Around the Solar System (SPYGLASS). I. Mapping Young Stellar Structures and Their Star Formation Histories", The Astrophysical Journal 917 (1): 23, doi:10.3847/1538-4357/ac0251, Bibcode: 2021ApJ...917...23K.
External links
- HR 8512
- Image Rho Aquarii Script error: The function "in_lang" does not exist.
- Aladin sky atlas, image Script error: The function "in_lang" does not exist.
