The physical and dynamical analysis of the suspected binary asteroid (12499) 1998 FR47

Abstract We present the R-band lightcurves of the Flora family asteroid (12499) 1998FR47, obtained in 2022 at two different astronomical sites: Bulgarian National Astronomical Observatory Rozhen (MPC 071) and Astronomical Station Vidojevica (MPC C89). The quadramodal lightcurves reveal a rotation period of6.172±0.003 h and an amplitude of about 0.44 mag. Using the lightcurve inversion method, with the combination of our dense lightcurves and the sparse data from DR3, we found the sidereal period, an indication of a retrograde rotation of (12499) and its low-convex resolution shape. Nonetheless, the unusual shape of the quadramodal lightcurve and its additional analysis reveals two possible periods, 3.0834±0.0085 h and 4.1245±0.0151 h, making the suspect that the asteroid might be a non-synchronised wide binary system. Spectral analysis of the asteroid using data from the GAIA DR3 shows that it is either an M- or an L-type object and maybe a piece of the first planetesimals to form in the Solar System protoplanetary disk. On the other hand, our studies of (12499)’s dynamical properties indicate a sig-nificantly shorter lifetime. The asteroid lies on the border of the 7:4 mean motionresonance with Mars (7M:4), alternating between being in and out of it for almost190 Myrs. During 200 Myrs of integration, (12499) visited other resonances inthe Flora family, but it never became a Near Earth Object (NEO). Additionalintegration of fictive objects from the 7M:4 resonance showed that there is apossibility of transpiration to the NEO region already at about 20 Myrs.