The Binary Nature of the Asteroid 2242 Balaton

Initial observations of 2242 Balaton indicated a rotation period of about 2.8 hours with some attenuation events. Further observations and analysis showed that 2242 is a binary asteroid with a primary period of 2.7979 ± 0.0001 h and amplitude of 0.18 mag; the orbital period of the secondary is 12.96 ± 0.01 h. Mutual events that are 0.03 to 0.08 magnitude deep indicate a lower limit on the secondary-to-primary mean-diameter ratio of 0.25. From sparse photometric data we also derived H = 13.31 ± 0.05, G = 0.22 ± 0.04.