Eta Delphini

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Eta Delphini
Diagram showing star positions and boundaries of the Delphinus constellation and its surroundings
Cercle rouge 100%.svg

Location of η Delphini (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Delphinus
Right ascension 20h 33m 57.04099s[1]
Declination +13° 01′ 38.1437″[1]
Apparent magnitude (V) 5.385[2]
Characteristics
Spectral type A3IVs[2]
U−B color index +0.04[3]
B−V color index +0.09[3]
Astrometry
Radial velocity (Rv) -25.00[2] km/s
Proper motion (μ) RA: 73.15[1] mas/yr
Dec.: 24.66[1] mas/yr
Parallax (π) 13.81 ± 1.17[1] mas
Distance 240 ± 20 ly
(72 ± 6 pc)
Other designations
η Del, 3 Del, BD+12° 4378, HD 195943, HIP 101483, SAO 106248, HR 7858, GC 28617[2]
Database references
SIMBAD data

Eta Delphini (η Del, η Delphini) is a star in the constellation Delphinus. It has an apparent magnitude of about 5.4, meaning that it is just barely visible to the naked eye. Based upon parallax measurements made by the Hipparcos spacecraft, this star is around 173 light years away from the Sun.[1]

Eta Delphini's spectral type is A3IVs, meaning it is an A-type subgiant with narrow absorption lines.[4] SIMBAD lists this star as a variable star.[2]

References[edit]

  1. ^ a b c d e f van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–664. Bibcode:2007A&A...474..653V. arXiv:0708.1752Freely accessible. doi:10.1051/0004-6361:20078357. 
  2. ^ a b c d e "eta Del". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 15 January 2016. 
  3. ^ a b Mermilliod, J.-C. (1986). "Compilation of Eggen's UBV data, transformed to UBV (unpublished)". Bibcode:1986EgUBV........0M. 
  4. ^ Allen, J. S. "The Classification of Stellar Spectra". UCL Department of Physics and Astronomy: Astrophysics Group. Retrieved 1 January 2014.