Where does moon get sulphur from? Meteoric or volcanic? Chandrayaan 3's latest insight

Pragyan rover has already confirmed the presence of several elements including sulphur and oxygen on the moon. On Thursday, Isro confirmed that another instrument of the Pragyan rover has found sulphur in the region -- the south pole of the moon -- through another technique. Two techniques confirming sulphur in the south pole region of the moon where Chandrayaan 3 successfully landed on August 23 will compel the scientists to explain the source of sulphur on the moon -- whether it is intrinsic or volcanic or meteoric. Read | What Chandrayaan 3 has found on moon so far: Oxygen, sulphur, iron, silicon

Sulphur usually originates from volcanic activities, but the scientific fraternity has not yet shed any light on the confirmed presence of sulphur on the moon. The earlier technique with detected sulphur was the Laser-Induced Breakdown Spectroscope onborad Pragyan rover. Now the Alpha Particle X-ray Spectroscope (APXS) has detected Sulphur and some other minor elements.

"This finding by Ch-3 compels scientists to develop fresh explanations for the source of Sulphur (S) in the area: intrinsic, volcanic, meteoritic," Isro tweeted in a fresh update of Chandrayaan 3.

Sulphur on the moon: What does it suggest?

Sulphur was not expected on the lunar soil. But two mechanisms of the rover confirmed the presence of sulphur. Aluminium, silicon, calcium, iron were expected and they have also been found. "What are lunar soil and rocks made of in the south polar region where Chandrayaan-3 landed? How's it different from other highland regions? These are the questions that the Chandrayaan-3 rover is trying to find answers with its scientific instruments," Isro said.

The presence of sulphur indicates that there could be water ice on the lunar surface. Or, there could be a volcanic eruption recently leading to the release of sulphur.

How does Alpha Particle X-ray Spectrometer (APXS) work?

Alpha Particle X-ray Spectrometer is the latest technique which confirmed the presence of sulphur on the moon. According to Isro, APXS instrument is best suited for in-situ analysis of the elemental composition of soil and rocks on the surface of planetary bodies having little atmosphere, such as the Moon. It carries radioactive sources that emit alpha particles and X-rays onto the surface sample. The atoms present in the sample in turn emit characteristic X-ray lines corresponding to the elements present. By measuring the energies and intensities of these characteristic X-rays, researchers can find the elements present and their abundances.