| Right Ascension | 15 : 03.8 (h:m) |
|---|---|
| Declination | +47 : 39 (deg:m) |
| Distance | 42 (ly) |
| Visual brightness | 5.80 .. 6.39 (mag) |
| Period | 0.268 (days) |
| Spectra type | G2V + G2V |
William Herschel had discovered and identified this star as the fainter component of a visual binary in 1781; he noted in his observing book (Herschel 1782):
The variability, suspected already in the later 19th century, was found in the 1910 (Hertzsprung), but judged as erroneous. It was eventually established in the 1920s: Mt. Wilson astronomers found its spectrum to resemble W Ursae Majoris (W UMa), i.e., a contact system. It is a short-period variable with rotationally broadened spectral lines (Adams et.al. 1921), and from spectra taken in 1926, its rotation period was found to be a bit more than a quarter of a day (Schilt 1926); a modern value is 6.42758 hours.
A concise description of the system is given in Eggen (1948).
The variable is the fainter componenti, 44 i Boo B of variable mag 5.8..6.4, the primary component, 44 i Boo A, is of about mag 5.19, so that the combined visual magnitude varies between 4.70..4.88 mag. The components orbit each other, or their center of mass, every 209.8 years in an orbit of about 46 AU average distance, but considerably high excentricity taking them between 22 and 69 AU away from each other. Because of the inclination against the line of view, the components seem to come apparently very close on mid-course, e.g. in the 1960s and 2020s (significantly below 1"), and go out to about 2" near periastron (2000s) and about 4" near apastron (1880s, 2090s). From Kepler's laws, a total mass of about 2.2 solar masses could be derived, with A: 1.13 solar masses, and the eclipsing binary pair B about the same total mass, so each of the two White Dwarf stars in B having about 0.55 .. 0.6 solar masses.