KIC 9532219 is a W UMa-type eclipsing binary with an orbital period of 0.1981549 d that is below the short-period limit ( \sim 0.22 d ) of the period distribution for contact binaries .
The Kepler light curve of the system exhibits striking light changes in both eclipse depths and light maxima .
Applying third-body and spot effects , the light-curve synthesis indicates that the eclipsing pair is currently in a marginal contact stage with a mass ratio of q =1.20 , an orbital inclination of i =66.0 deg , a temperature difference of \Delta ( T _ { 1 } – T _ { 2 } ) =172 K , and a third light of l _ { 3 } =75.9 % .
To understand the light variations with time , we divided up the light curve into 312 segments and separately analyzed them .
The results reveal that variation of eclipse depth is primarily caused by changing amounts of contamination due to the nearby star KIC9532228 between the Kepler Quarters and that the variable O ’ Connell effect originates from the starspot activity on the less massive primary component .
Based on our light-curve timings , a period study of KIC 9532219 indicates that the orbital period has varied as a combination of a downward parabola and a light-travel-time ( LTT ) effect due to a third body , with a period of 1196 d and a minimum mass of 0.0892 M _ { \odot } in an eccentric orbit of 0.150 .
The parabolic variation could be a small part of a second LTT orbit due to a fourth component in a wider orbit , instead of either mass transfer or angular momentum loss .