SZ Crateris

SZ Crateris is a binary star system in the southern constellation Crater. Both components belong to the main sequence: the primary star has a spectral classification of K5V while the secondary is a red dwarf of spectral class M0V. The radius of the primary is about 66% the radius of the Sun, while the secondary member is only about 42% of the solar radius. In 1994, the two stars were separated by 5.1 arc seconds, which is equivalent to 112.41 astronomical units.

SZ Crateris is classified as a marginal BY Draconis variable, and has an optical variability cycle of 11.58 days. (The star causing the variability is unspecified.) Compared to the Sun, SZ Crateris has a slightly higher proportion of elements other than hydrogen and helium. Based upon gyrochronology, the estimated age of this star is under 200 million years.

The SZ Crateris system is a member of the Ursa Major moving group of stars that have similar motions through space. The space velocity components of this system are U = +13.86 ± 0.37, V = –3.51 ± 1.97 and W = +1.65 ± 1.53 km/s. It is on an orbit through the Milky Way that has an orbital eccentricity of 0.092, which will bring it as close as 26.06 kly to the galactic core, and as distant as 31.31 kly. The inclination of the orbit carries the system as much as 0.352 kly from the plane of the galactic disk.