Characteristics of the Lunar Samples Returned by the Chang’E-5 Mission

Forty-five years after the Apollo and Luna missions returned lunar samples,China’s Chang’E-5（CE-5）mission collected new samples from the mid-latitude region in the northeastern Oceanus Procellarum of the Moon.Our study shows that 95% of CE-5 lunar soil sizes are found to be within the range of 1.40-9.35 μm,while 95% of the soils by mass are within the size range of 4.84-432.27 μm.The bulk density,true density and specific surface area of CE-5 soils are 1.2387 g/cm~3,3.1952 g/cm~3 and 0.56 m~2/g,respectively.Fragments from the CE-5 regolith are classified into igneous clasts（mostly basalt）,agglutinate and glass.A few breccias were also found.The minerals and compositions of CE-5 soils are consistent with mare basalts and can be classified as low-Ti/low-Al/low-K type with lower rare-earth-element contents than materials rich in potassium,rare earth element and phosphorus.CE-5 soils have high FeO and low Mg index,which could represent a new class of basalt.