The Mineralogy of Cometary Dust

摘要: Cometary dust is a heterogeneous mixture of unequilibrated olivine and pyroxenes, amorphous silicates, Fe-Ni sulfides, minor amounts oxides other minerals. While forsterite Mg2SiO4 enstatite MgSiO3 are the most common silicate minerals, both pyroxenes also show wide range in Mg/Fe at least some comets. Carbon enriched relative to CI chondrites; significant fraction carbon form organic refractory material. The return particulate sample from ecliptic comet 81P/Wild 2 has opened up new window for revealing mineralogy level detail not previously possible. interesting result Wild date discovery calcium aluminum-rich inclusions (CAI) similar those found primitive meteorites; chondrule fragments present.