3-dimensional modeling for the orbit of asteroidal satellite of 65803 Didymos

Abstract

We present the results of photometric observations of the near-Earth asteroid 65803 Didymos (1996 GT) in 2003 and 2005. Didymos has a complex lightcurve consisting of mainly two independent components. It suggests that the two-body system as asynchronous binary displaying the mutual eclipse/occultation by the satellite. Although the taxonomic type was revealed an M-type from the reflectance spectrum and phase curve, the bulk density is estimated at 1.4 +/- 0.3 g/cm³ by the analysis of the satellite orbit. This could indicate that Didymos is composed of, not metallic but, chondritic materials.