Eta1 Doradus

Eta¹ Doradus, Latinized from η¹ Doradus, is a star in the southern constellation of Dorado. It is visible to the naked eye as a dim, white-hued star with an apparent visual magnitude of 5.72.^[2] This object is located approximately 335 light years distant from the Sun, based on parallax, and is drifting further away with a radial velocity of +18 km/s.^[2] It is circumpolar south of latitude 24°S.

For other stars with this Bayer designation, see η Doradus.

Eta¹ Doradus

Observation data Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation	Dorado
Right ascension	06h 06m 09.38154s[1]
Declination	−66° 02′ 22.6304″[1]
Apparent magnitude (V)	5.72[2]
Characteristics
Spectral type	A0V[3]
U−B color index	−0.024±0.004[2]
B−V color index	−0.03[4]
Astrometry
Radial velocity (Rv)	+17.6±4.3[2] km/s
Proper motion (μ)	RA: +13.656[1] mas/yr Dec.: +27.815[1] mas/yr
Parallax (π)	9.7251 ± 0.1094 mas[1]
Distance	335 ± 4 ly (103 ± 1 pc)
Absolute magnitude (MV)	+0.75[2]
Details
Mass	2.46[5] M☉
Luminosity	49[6] L☉
Surface gravity (log g)	4.09±0.08[7] cgs
Temperature	10,325±240[7] K
Rotational velocity (v sin i)	149[5] km/s
Age	94[5] Myr
Other designations
η1 Dor, CPD−66° 493, GC 7813, HD 42525, HIP 28909, HR 2194, SAO 249448, PPM 355182, TYC 8905-1950-1[8]
Database references
SIMBAD	data

This object is an A-type main-sequence star with a stellar classification of A0V.^[3] It is 94^[5] million years old with a high rotation rate, showing a projected rotational velocity of 149.^[5] The star has 2.46^[5] times the mass of the Sun and is radiating 49^[6] times the Sun's luminosity from its photosphere at an effective temperature of 10,325 K.^[7] It is the southern pole star of Venus.^[9]

References

1. 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.
2. 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.
3. Houk, Nancy (1978), Michigan catalogue of two-dimensional spectral types for the HD stars, vol. 1, Ann Arbor: Dept. of Astronomy, University of Michigan, Bibcode:1975mcts.book.....H.
4. HR 2194, database entry, The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version), D. Hoffleit and W. H. Warren, Jr., CDS ID V/50. Accessed on line September 25, 2008.
5. David, Trevor J.; Hillenbrand, Lynne A. (2015), "The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets", The Astrophysical Journal, 804 (2): 146, arXiv:1501.03154, Bibcode:2015ApJ...804..146D, doi:10.1088/0004-637X/804/2/146, S2CID 33401607.
6. McDonald, I.; et al. (2012), "Fundamental Parameters and Infrared Excesses of Hipparcos Stars", Monthly Notices of the Royal Astronomical Society, 427 (1): 343–57, arXiv:1208.2037, Bibcode:2012MNRAS.427..343M, doi:10.1111/j.1365-2966.2012.21873.x, S2CID 118665352.
7. Decin, L.; et al. (September 2004), "MARCS: Model Stellar Atmospheres and Their Application to the Photometric Calibration of the Spitzer Space Telescope Infrared Spectrograph (IRS)", Astrophysical Journal Supplement, 154 (1): 408–412, arXiv:astro-ph/0406104, Bibcode:2004ApJS..154..408D, doi:10.1086/422884. See Table 1.
8. "HD 42525". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved September 25, 2008.
9. Archinal, Brent A.; A'Hearn, Michael F.; Bowell, Edward G.; Conrad, Albert R.; Consolmagno, Guy J.; et al. (2010). "Report of the IAU Working Group on Cartographic Coordinates and Rotational Elements: 2009" (PDF). Celestial Mechanics and Dynamical Astronomy. 109 (2): 101–135. Bibcode:2011CeMDA.109..101A. doi:10.1007/s10569-010-9320-4. S2CID 189842666. Archived from the original (PDF) on 2016-03-04. Retrieved 2018-09-06.

External links

• 2004. Starry Night Pro, Version 5.8.4. Imaginova. ISBN 978-0-07-333666-4. www.starrynight.com