Binary star in the constellation Pisces
Pi Piscium Location of π Piscium (circled)
Observation dataEpoch J2000.0 Equinox J2000.0 (ICRS ) Constellation Pisces Right ascension 01h 37m 05.91523s [ 1] Declination +12° 08′ 29.5186″[ 1] Apparent magnitude (V)5.60[ 2] [ 3] Characteristics Spectral type F0 V[ 4] [ 3] Astrometry Radial velocity (Rv )−1.0[ 2] km/s Proper motion (μ)RA: −77.29[ 1] mas /yr Dec.: +9.13[ 1] mas /yr Parallax (π)28.50± 0.97 mas [ 1] Distance 114 ± 4 ly pc ) Absolute magnitude (MV )+2.94[ 2] Details[ 3] A Mass 1.42 M ☉ Radius 1.68[ a] R ☉ Luminosity 5.45[ b] L ☉ Surface gravity (log g )4.16 cgs Temperature 6,810 K Metallicity [Fe/H] dex Rotational velocity (v sin i )105.9[ 2] Age 2.0[ 5] Gyr B Mass 0.75 M ☉ Radius 0.69[ a] R ☉ Luminosity 0.207[ b] L ☉ Temperature 4,700 K Other designations π Psc ,102 Piscium ,BD +11°205FK5 1046GC 1954HD 9919HIP 7535HR 463SAO 92536PPM 117498[ 6] Database references SIMBAD data
Pi Piscium (π Piscium ) is aspectroscopic binary [ 3] zodiac constellation ofPisces . It is faintly visible to the naked eye, having anapparent visual magnitude of 5.60.[ 2] parallax shift of 28.50 mas as seen from Earth,[ 1] light years distant. It is a member of thethin disk population of theMilky Way .[ 7]
The primary, ofapparent magnitude 5.56,[ 3] F-type main-sequence star with astellar classification of F0 V.[ 4] [ 5] main sequence lifetime[ 8] projected rotational velocity of 105.9 km/s.[ 2] mass of the Sun and 1.68[ a] Sun's radius . It is radiating 5.5[ b] Sun's luminosity at aneffective temperature of 6,810 K.[ 3] [ 9]
The secondary, ofapparent magnitude 9.56, is aK-dwarf star . It is 0.75 times as massive than the Sun, 0.69[ a] [ b] effective temperature is 4,700 K,[ 3] [ 9]
Analysis of its motion suggest Pi Piscium may be a member of theUrsa Major association , but higher-quality observations are needed to confirm this.[ 3]
InChinese ,右更 Yòu Gèng Official in Charge of the Pasturing η Piscium ,ρ Piscium ,ο Piscium and104 Piscium . Consequently, theChinese name for π Piscium itself is右更三 Yòu Gèng sān the Third Star of Official in Charge of the Pasturing .)[ 10]
^a b c d Calculated, using theStefan-Boltzmann law and the star'seffective temperature and luminosity, with respect to thesolar nominal effective temperature of 5,772 K :( 5 , 772 6 , 810 ) 4 ⋅ 5.45 = 1.68 R ⊙ . {\displaystyle {\sqrt {{\biggl (}{\frac {5,772}{6,810}}{\biggr )}^{4}\cdot 5.45}}=1.68\ R_{\odot }.} ( 5 , 772 4 , 700 ) 4 ⋅ 0.207 = 0.69 R ⊙ . {\displaystyle {\sqrt {{\biggl (}{\frac {5,772}{4,700}}{\biggr )}^{4}\cdot 0.207}}=0.69\ R_{\odot }.} ^a b c d Calculated from the equation L = 100.4 • (4.74 − Mbol , where Mbol is theabsolute bolometric magnitude . For component A, a value of 2.90 is used, while for B a value of 6.45 is used. ^a b c d e f van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction",Astronomy and Astrophysics ,474 (2):653– 664,arXiv :0708.1752 Bibcode :2007A&A...474..653V ,doi :10.1051/0004-6361:20078357 ,S2CID 18759600 . ^a b c d e f Paunzen, E.; et al. (July 2014), "Investigating the possible connection between λ Bootis stars and intermediate Population II type stars",Astronomy & Astrophysics ,567 : 8,arXiv :1406.3936 Bibcode :2014A&A...567A..67P ,doi :10.1051/0004-6361/201423817 ,S2CID 56332289 , A67. ^a b c d e f g h Fuhrmann, Klaus; Chini, Rolf (January 2019), "On the Secondary of π Piscium",Research Notes of the AAS ,3 (1): 10,Bibcode :2019RNAAS...3...10F ,doi :10.3847/2515-5172/aafd39 ISSN 2515-5172 . ^a b Cowley, Anne; Fraquelli, Dorothy (February 1974), "MK Spectral Types for Some Bright F Stars",Publications of the Astronomical Society of the Pacific ,86 (509): 70,Bibcode :1974PASP...86...70C ,doi :10.1086/129562 ^a b Holmberg, J.; et al. (July 2009), "The Geneva-Copenhagen survey of the solar neighbourhood. III. Improved distances, ages, and kinematics",Astronomy and Astrophysics ,501 (3):941– 947,arXiv :0811.3982 Bibcode :2009A&A...501..941H ,doi :10.1051/0004-6361/200811191 ,S2CID 118577511 . ^ "pi. Psc" .SIMBAD Centre de données astronomiques de Strasbourg . Retrieved2017-07-25 .{{cite web }}: CS1 maint: postscript (link )^ Ramírez, I.; et al. (September 2012), "Lithium Abundances in nearby FGK Dwarf and Subgiant Stars: Internal Destruction, Galactic Chemical Evolution, and Exoplanets",The Astrophysical Journal ,756 (1): 46,arXiv :1207.0499 Bibcode :2012ApJ...756...46R ,doi :10.1088/0004-637X/756/1/46 ,S2CID 119199829 . ^ Zorec, J.; Royer, F. (January 2012), "Rotational velocities of A-type stars. IV. Evolution of rotational velocities",Astronomy & Astrophysics ,537 : A120,arXiv :1201.2052 Bibcode :2012A&A...537A.120Z ,doi :10.1051/0004-6361/201117691 ,S2CID 55586789 . ^a b "The Colour of Stars" ,Australia Telescope, Outreach and Education , Commonwealth Scientific and Industrial Research Organisation, December 21, 2004, archived fromthe original on 2013-12-03, retrieved2012-01-16 ^ (in Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 5 月 19 日 Archived 2016-03-03 at theWayback Machine
