Kruger 60

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**Kruger 60 A/B**
Observation data Epoch J2000
Constellation (pronunciation)	Cepheus
Right ascension	22h 27m 59.5s
Declination	+57° 41' 45"
Apparent magnitude (V)	9.59/11.40
Characteristics
Spectral type	M3 V/M4 Ve
U-B color index	1.27/1.3
B-V color index	1.65/1.8
Variable type	None/Flare star
Astrometry
Radial velocity (R_v)	-33.1/-31.9 km/s
Proper motion (μ)	RA: -870.23 mas/yr Dec.: -471.10 mas/yr
Parallax (π)	248.06 ± 1.39 mas
Distance	13.15 ± 0.07 ly (4.03 ± 0.02 pc)
Absolute magnitude (M_V)	11.76/13.37
Details
Mass	0.27/0.16 M_☉
Radius	0,33/0,23 Rs R_☉
Luminosity	0.010/0.0034 L_☉
Temperature	3180/2890 K K
Metallicity	?
Rotation	?
Age	? years
Visual binary orbit
Companion	Kruger 60 B
Period (P)	44.67 yr
Semimajor axis (a)	2.383"
Eccentricity (e)	0.41
Inclination (i)	167.2°
Longitude of the node (Ω)	154.5°
Periastron epoch (T)	1970.22
Other designations
DO Cephei, Gl 232-075, GJ 860 A/B, BD +56°2783, HD 239960, LHS 3814/3815, GCTP 5438.00, ADS 15972, Vys 207 A/B, HIP 110893.
Database references
SIMBAD	data

Kruger 60 is a binary star system composed of A and B components, both of which are red dwarf stars. These stars orbit each other every 44.6 years. The fainter companion B is a flare star and has been given the variable star designation "DO Cephei". It is an irregular flare that typically doubles in brightness and then returns to normal over an 8 minute period.

On average, the two stars are separated by 9.5 AUs, which is roughly the average distance of Saturn from the Sun. However, their eccentric mutual orbit causes their distance to vary between 5.5 AUs at periastron, to 13.5 at apastron.