The moon has an excess of sodium, which has been discovered for the first time by Chandrayaan-2, a spacecraft that has been orbiting the moon since 2019. The latest discoveries offer a way to investigate surface-exosphere interactions on the moon, which will help in the creation of models that are analogous for mercury and other airless worlds in our solar system and beyond.

The Chandrayaan-2 orbiter's X-ray spectrometer, known as 'CLASS,' first detected an excess of sodium on the moon, according to the Indian Space Research Organization, or ISRO.

Isro announced in a statement that the Chandrayaan-1 X-ray Fluorescence Spectrometer (C1XS) discovered sodium from its distinctive line in X-rays, opening up the potential of mapping the sodium content of the Moon.

The exceptional sensitivity and capability of the Chandrayaan-2Large Area Soft X-ray Spectrometer, or CLASS, developed by the UR Rao Satellite Centre of Isro, enable it to produce clear signals of the sodium line.

According to a recent study, a portion of the signal might originate from a thin layer of sodium atoms that are weakly bonded to the lunar grains. If the sodium atoms were a component of the lunar minerals, they would be more easily pushed out of the surface by solar wind or ultraviolet light.

Additionally, Chandrayaan-2 discovered a diurnal change in the surface sodium that would account for the exosphere's ongoing atomic supply. In addition, sodium was discovered in the moon's thin atmosphere, where atoms seldom ever collide. According to ISRO, this area, known as the 'exosphere,' starts at the moon's surface and spans thousands of kilometres before merging with interplanetary space.

The Moon's ionosphere has a plasma density in the wake region that is at least one order of magnitude more than what is present on the day side, Chandrayaan-2, which is lingering in lunar orbit, has previously discovered. Since the spacecraft entered orbit in 2019, it has been examining the lunar surface.