44 Boötis
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Boötes |
| Right ascension | 15h 03m 47.29565s |
| Declination | +47° 39′ 14.6228″ |
| Apparent magnitude (V) | 4.70 - 4.84 (5.136 / 6.004) |
| Characteristics | |
| Spectral type | G0Vnv + (K0V + K4V) |
| U−B color index | 0.09 |
| B−V color index | 0.65 |
| Variable type | W UMa |
| Astrometry | |
| Radial velocity (Rv) | −17.89 km/s |
| Proper motion (μ) | RA: −445.84 mas/yr Dec.: 19.86 mas/yr |
| Parallax (π) | 78.39±1.03 mas |
| Distance | 41.6 ± 0.5 ly (12.8 ± 0.2 pc) |
| Absolute magnitude (MV) | +2.211 / +5.38 |
| Orbit | |
| Primary | 44 Boo A |
| Name | 44 Boo B |
| Period (P) | 209.8±3.3 yr |
| Semi-major axis (a) | 3.666±0.021″ |
| Eccentricity (e) | 0.5111±0.0065 |
| Inclination (i) | 83.55±0.05° |
| Longitude of the node (Ω) | 57.14±0.06° |
| Periastron epoch (T) | B 2012.04±0.26 |
| Argument of periastron (ω) (secondary) | 39.86±0.68° |
| Orbit | |
| Primary | 44 Boo Ba |
| Name | 44 Boo Bb |
| Period (P) | 0.267818 days |
| Semi-major axis (a) | 2.015 R☉ |
| Eccentricity (e) | 0.0 |
| Inclination (i) | 72.8° |
| Semi-amplitude (K1) (primary) | 231.31 km/s |
| Semi-amplitude (K2) (secondary) | 112.70 km/s |
| Details | |
| 44 Boo A | |
| Mass | 1.04±0.10 M☉ |
| Luminosity | 1.552 L☉ |
| Surface gravity (log g) | 4.33 cgs |
| Temperature | 5,877 K |
| Metallicity [Fe/H] | −0.24 dex |
| Age | 1.4–1.5 Gyr |
| 44 Boo Ba | |
| Mass | 0.98 M☉ |
| Radius | 0.87 R☉ |
| Luminosity | 0.51 L☉ |
| Temperature | 5,300 K |
| 44 Boo Bb | |
| Mass | 0.55 M☉ |
| Radius | 0.66 R☉ |
| Luminosity | 0.24 L☉ |
| Temperature | 5,035 K |
| Other designations | |
| Quadrans, i Boötis, 44 Boo, BD+48°2259, FK5 3182, GJ 575, HD 133640, HIP 73695, HR 5618, SAO 45357, ADS 9494, CCDM 15038+4739 | |
| Database references | |
| SIMBAD | data |
| A | |
| B | |
44 Boötis, also known as i Boötis, is a triple star system in the constellation Boötes. It is approximately 41.6 light years from Earth. Its three components are designated 44 Boötis A (with the proper name Quadrans), 44 Boötis Ba, and 44 Boötis Bb.
44 Boötis B is a contact binary of the W Ursae Majoris type. It is the nearest contact binary star.