Three-dimensional structures of Stardust grains

Abstract

Dust from comet 81P/Wild2 has been successfully recovered in the Stardust mission. We obtained three-dimensional structures of 16 particles in a few tens of mm in size, which were extracted from impact tracks in aerogel collectors by using SR imaging microtomography.Imaging experiments were performed at BL47XU of Spring-8 at 7.13 keV with the voxel size of 76.5nm, which gives the effective spatial resolution of a few hundreds nm. The cosmic dust particles are largely classified into three types; (1) crystalline, (2) amorphous-rich and (3) others. We will report the features of the individual captured particles by considering their mineral compositions by XRD too.