Tau2 Serpentis

From Wikipedia, the free encyclopedia
Jump to: navigation, search
For other stars with this Bayer designation, see Tau Serpentis.
τ2 Serpentis
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Serpens
Right ascension 15h 32m 09.6751s[1]
Declination +16° 03′ 22.208″[1]
Apparent magnitude (V) 6.218[1]
Characteristics
Spectral type B9V[1]
U−B color index −0.23[2]
B−V color index −0.05[2]
Astrometry
Radial velocity (Rv) −18 ± 5[1] km/s
Proper motion (μ) RA: −2.87[1] mas/yr
Dec.: 6.76[1] mas/yr
Parallax (π) 7.56 ± 0.80[1] mas
Distance approx. 430 ly
(approx. 130 pc)
Absolute magnitude (MV) 0.6[3]
Details
Radius 2.7[4] R
Rotational velocity (v sin i) 175[2] km/s
Other designations
τ2 Ser, Tau2 Serpentis, Tau2 Ser, 12 Serpentis, 12 Ser, BD+16 2797, GC 20880, HD 138527, HIP 76069, HR 5770, PPM 131484, SAO 101600.[1]
Database references
SIMBAD data

Tau2 Serpentis (Tau2 Ser, τ2 Serpentis, τ2 Ser) is a B-type main sequence star in the constellation of Serpens, approximately 430 light-years from Earth. It has an apparent visual magnitude of approximately 6.218.[1]

References[edit]

  1. ^ a b c d e f g h i j * 12 Ser -- Star, database entry, SIMBAD. Accessed on line September 19, 2008.
  2. ^ a b c HR 5770, 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 19, 2008.
  3. ^ From apparent magnitude and parallax.
  4. ^ HD 138527, database entry, Catalog of Apparent Diameters and Absolute Radii of Stars (CADARS), 3rd edition, L. E. Pasinetti-Fracassini, L. Pastori, S. Covino, and A. Pozzi, CDS ID II/224. Accessed on line September 19, 2008.