Pragyan confirms sulphur near south pole of moon; search on for hydrogen

Subject :Science and technology

Section: Space technology

Pragyan Rover’s Discoveries on Moon’s Surface

The Chandrayaan-3 mission’s rover, Pragyan, has confirmed the presence of sulphur on the moon’s surface, for the first time specifically near its south pole.
Apart from sulphur, preliminary analyses identified elements like aluminum, calcium, iron, chromium, titanium, manganese, silicon, and oxygen on the lunar surface.
In-situ measurements were conducted by the Laser-Induced Breakdown Spectroscopy (LIBS) instrument aboard the rover.
Unlike the orbiters, which couldn’t provide such information, the rover’s direct measurements have established the unambiguous presence of sulfur.
The ISRO is currently conducting a search for hydrogen (H), another element of interest.

Laser-Induced Breakdown Spectroscopy (LIBS) Explained

Introduction:

LIBS is a rapid chemical analysis technology that employs short laser pulses to create micro-plasma on a sample’s surface.

Advantages of LIBS:

Requires no sample preparation.
Offers rapid measurements, often within a few seconds.
Covers a wide range of elements, including lighter ones.
Supports versatile sampling protocols, including surface rastering and depth profiling.

Process of Laser-Induced Breakdown:

A short-pulse laser is focused on the sample, causing ablation (removal of sample mass).
Ablated mass interacts with the trailing laser pulse, forming a high-energy plasma.
Plasma Formation and Cooling:
1. Plasma temperature can exceed 30,000K in its early phase.
2. Plasma cools, causing electrons to fall to ground states and emit light with discrete spectral peaks.
Emission of Spectral Peaks:
1. Unique spectral peaks correspond to different elements in the periodic table.
2. By identifying these peaks, the chemical composition of the sample can be determined.

Additional Information:

The Union Cabinet commemorates Chandrayaan-3’s success and designates August 23 as National Space Day.