Evidence of ancient magma ocean remnants found at the south pole of the moon

New evidence of ancient magma ocean discovered at the south pole of the moon, brought by Chandrayaan-3.

On August 22, a planetary science paper published in the renowned international academic journal Nature stated that there is evidence of an ancient magma ocean at the south pole of the moon.

For a long time, lunar geological research has mainly relied on samples collected by missions in the mid-latitudes of the moon, such as the Apollo program. However, in August 2023, the Vikram lander of India's Chandrayaan-3 mission successfully soft-landed near the south pole of the moon, bringing new opportunities for lunar research.

Subsequently, the Pragyan lunar rover of Chandrayaan-3 used the on-board alpha particle X-ray spectrometer to conduct 23 measurements at different locations along a 103-meter-long path on the lunar surface to detect the elemental composition of the lunar soil. By ***yzing these measurement results, the researchers found a relatively uniform elemental composition of the lunar soil around the lander, mainly iron-bearing anorthosite. This compositional measurement result is between the samples collected from the lunar equatorial region by Apollo 16 and Luna 20, supporting the lunar magma ocean hypothesis. According to this hypothesis, when the moon cooled during its formation, the low-density iron-bearing anorthosite floated to the surface, and heavier minerals sank to form the lunar mantle.

However, the lunar rover also detected magnesium-bearing minerals, which cannot be explained by the lunar magma ocean hypothesis and may be deep-seated materials churned up by the nearby South Pole-Aitken impact.

The authors of the paper concluded that the composition at the Vikram landing site of the Chandrayaan-3 mission is consistent with the lunar magma ocean hypothesis, which predicts that the lunar highlands may be formed by the floating of lighter anorthosite. This discovery provides important clues for further exploring the formation and evolution of the moon.