X-ray ultra micrographs of (a) an opaque dumbbel and (b) an opaque rod shaped particle:

• the dumbbel shaped particle has clearly been formed by a droplet gaining rotational momentum: the pores are located towards the center, while the more dense inclusions are found at the extremities,
• in the rod-shaped particle, the pores are no-longer spherical and their location is random. This particle has probably been formed during the translational break-up of a thin jet or spray of molten regolith.