Published on: March 9, 2022




New data from Chandra’s Atmospheric Composition Explorer-2 (CHACE-2) mass spectrometer on Chandrayaan-2 show the distribution of Argon-40 gas in the lunar ‘exosphere’, beyond the areas this was known to exist


  • It is India’s second mission to the moon.
  • It aims to explore the Moon’s south polar region.
  • The mission is an important step in India’s plans for planetary exploration, a program known as Planetary Science and Exploration (PLANEX).
  • There are three components of the mission, an orbiter, a lander and a rover.
  • The mission payloads include — Terrain Mapping Camera which will generate a Digital Elevation Model (DEM) of the entire moon, Chandrayaan 2 Large Area Soft X-ray Spectrometer which will test the elemental composition of the Moon’s surface Solar X-Ray Monitor which will provide solar X-ray spectrum inputs for CLASS.
  • The orbiter will be deployed at an altitude of 100 kilometers above the surface of the Moon. The lander will then separate from the orbiter, and execute a soft landing on the surface of the Moon, unlike the previous mission which crash landed near the lunar south pole.
  • The lander, rover and orbiter will perform mineralogical and elemental studies of the lunar surface.
  • The rover is named Pragyan.
  • The mission’s lander is named Vikram after Dr Vikram A Sarabhai, the Father of the Indian Space Programme.
    • Of the four, two — RAMBHA-LM (Radio Anatomy of Moon Bound Hypersensitive Ionosphere and Atmosphere-Langmuir Probe) and ChaSTE (Chandra’s Surface Thermophysical Experiment) — are on the lander, which is believed to have crash-landed during soft-landing mission on the lunar south pole.
    • RAMBHA, which is expected to provide valuable information on the lunar ionosphere, is made up of two components; one aboard the lander and the other, on the orbiter.
    • SPL’s payload on the orbiter, CHACE-2 (short for Chandra’s Altitudinal Composition Explorer) is functioning perfectly.
    • CHACE-2 is designed to measure the composition of the lunar exosphere and is an improvement on CHACE, which flew aboard the Moon Impact Probe (MIP) on the 2008 Chandrayaan-1 mission.
    • The second SPL payload, the RAMBHA-Dual Frequency Radio Science experiment (RAMBHA-DFRS), will study altitude variations of electron density in the moon’s ionosphere.
    • The hardware for this payload was developed by the ISRO Telemetry, Tracking and Command Network, Bengaluru.