44 Boötis

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44 Boötis
Observation data
Epoch J2000      Equinox J2000
Constellation Boötes
Right ascension 15h 03m 47.304s
Declination +47° 39′ 14.616″
Apparent magnitude (V) 4.75
Characteristics
Spectral type G0Vnv
U−B color index 0.11
B−V color index 0.65
Variable type W UMa variable
Astrometry
Radial velocity (Rv) -30.8 km/s
Proper motion (μ) RA: -436.26 mas/yr
Dec.: 18.93 mas/yr
Parallax (π) 78.39 ± 1.03[1] mas
Distance 41.6 ± 0.5 ly
(12.8 ± 0.2 pc)
Absolute magnitude (MV) 2.211[1]
Details
Mass 1.1/1+0.79 M
Radius 1.1/0.89+0.66 R
Luminosity 1.2/1 L
Temperature 5900/5500+5000 K
Rotation <= 16 km/s
0,0095423 Year
Age (1.4–1.5) × 109[2] years
Orbit
Companion 44 Boötis B
Period (P) 225 yr
Semi-major axis (a) 3.772"
Eccentricity (e) 0.43
Inclination (i) 83.9°
Longitude of the node (Ω) 57.8°
Periastron epoch (T) 2021
Other designations
i Boötis, HR 5618, HD 133640, Gl 575, BD+48°2259, HIP 73695, SAO 45357, GC 20281, ADS 9494, CCDM 15038+4739.
Database references
SIMBAD data
Data sources:
Hipparcos Catalogue,
CCDM (2002),
Bright Star Catalogue (5th rev. ed.)

44 Boötis or i Boötis is a triple star system in the constellation Boötes. It is approximately 41.6 light years from Earth.

The primary component, 44 Boötis A, is a yellow-white G-type main sequence dwarf with a mean apparent magnitude of +4.83. The companion component, 44 Boötis B, is a W Ursae Majoris variable spectroscopic binary. The brightness of the binary varies from magnitude +5.8 to +6.40 with a period of 6.43 hours. The components of the eclipsing binary are separated by 0.008 Astronomical Units, roughly 3 times the distance of the Moon from Earth.

The 44 Boötis system is 42 light-years (13 parsecs) from Earth.[1]

References[edit]

  1. ^ a b c Eker, Z.; Bilir, S.; Yaz, E.; Demircan, O.; Helvaci, M. (2009). "New absolute magnitude calibrations for W Ursa Majoris type binaries". Astronomische Nachrichten 330 (1): 68–77. arXiv:0807.4989. Bibcode:2009AN....330...68E. doi:10.1002/asna.200811041. 
  2. ^ Mamajek, Eric E.; Hillenbrand, Lynne A. (November 2008). "Improved Age Estimation for Solar-Type Dwarfs Using Activity-Rotation Diagnostics". The Astrophysical Journal 687 (2): 1264–1293. arXiv:0807.1686. Bibcode:2008ApJ...687.1264M. doi:10.1086/591785.