9 Pegasi is defined and used as an MK standard star for the spectral type G5 Ib.[8][9] It is ayellow supergiant nearly two thousand times more luminous than the sun and sixty times larger. It has been reported to be slightly variable and is listed in theNew Catalogue of Suspected Variable Stars with a magnitude range of 4.20 to 4.35.[10]
9 Pegasi does not have aBayer designation although it is brighter than several stars in Pegasus that do such asτ,φ, andσ Pegasi. It is the 9th star numbered byFlamsteed in order ofright ascension. In the 1795 French-language Fortin-Flamsteed edition of theAtlas Coelestis, 9 Pegasi is labelled with the letter "g".[11]
^abcDucati, J. R. (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system".CDS/ADC Collection of Electronic Catalogues.2237.Bibcode:2002yCat.2237....0D.
^Morgan, William Wilson; Keenan, Philip Childs; Kellman, Edith (1943). "An atlas of stellar spectra, with an outline of spectral classification".Chicago.Bibcode:1943assw.book.....M.
^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.Bibcode:2009yCat....102025S.
^Flamsteed, John; Fortin, Jean Nicolas; De Lalande, Joseph Jerome Lefrancais (1795). "Atlas celeste".Paris: Delamarche.Bibcode:1795atce.book.....F.