A study conducted by a group of professors led by Meng-Hua Zhu, associate professor of the State Key Laboratory of Lunar and Planetary Sciences at Macau University of Science and Technology (MUST), was published in the journal Nature on July 10.
In the study titled “Reconstructing the late-accretion history of the Moon,” the team carried out a detailed reconstruction that explains the relative scarcity of highly siderophile (iron-loving) elements on the moon, and gives new insight into the development and late accretion (growth) history of the moon.
Researchers modeled the impact events that would have brought the material to the earth and moon, validated using the number of actual craters on the moon. They found that because of the moon’s smaller size and lower gravity, meteorites that hit the moon left behind relatively less material than those that hit the earth.
Zhu and his colleagues calculated that the highly siderophile elements would have been retained in the lunar crust and mantle 4.35 billion years ago, later than previously thought and around the time the magma ocean covering the moon solidified. The highly siderophile elements arriving before that time would have been absorbed into the moon’s iron core.
Together, these factors account for the discrepancy in highly siderophile elements between the earth and moon. JZ