PHOTOMETRIC STUDY OF NPA ROTATOR (5247) KRYLOV

We conduct BVRI and R band photometric observations of asteroid (5247) Krylov from January 2016 to April 2016 for 51 nights using the Korea Microlensing Telescope Network (KMTNet). The color indices of (5247) Krylov at the light curve maxima are determined as B − V = 0.841± 0.035, V −R = 0.418± 0.031, and V − I = 0.871± 0.031 where the phase angle is 14.1. They are acquired after the standardization of BVRI instrumental measurements using the ensemble normalization technique. Based on the color indices, (5247) Krylov is classified as a S-type asteroid. Double periods, that is, a primary period P1 = 82.188 ± 0.013h and a secondary period P2 = 67.13 ± 0.20 h are identified from period searches of its R band light curve. The light curve phases with P1 and this indicate that it is a typical Non-Principal Axis (NPA) asteroid. We discuss the possible causes of its NPA rotation.