Double Star in Canes Venatici
Cor Caroli is the brightest star in the small constellation Canes Venactici (the hunting dogs). It is easy to find below the handle of the Big Dipper. Through a telescope, Cor Caroli can be seen as a wide double star, with a bright white primary star and a dimmer companion. The primary star is a variable that changes slightly in brightness over a period of about 5.5 days. It also has an intense magnetic field.
The distance between these two stars is about 680 astronomical units (that is, 680 times the average distance between the Sun and the Earth).
| Magnitudes | 2.9, 5.5 |
| Diameters (Sun=1) | 2.7, 1.7 |
| Angular Separation | 19.3" |
| Separation (AU) | 680 |
| Distance (light yrs) | 115 |
| Right Ascension | 12:56.0 |
| Declination | +38 19 |
| Field of View | 26' x17' |
Image details: Five exposures each of 1/40, 1/5, 1, and 4 seconds at ISO 12800, taken with a Canon T6i camera through a Meade 14” LX850 telescope at f/8.
April 2018