Chaste: SCIENCE & TECHNOLOGY

NEWS: Chandranan’s ChaSTE scores a first after taking moon’s temperature

WHAT’S IN THE NEWS?

ChaSTE, part of Chandrayaan-3's Vikram lander, successfully measured in situ temperature variations near the moon’s south pole using a rotation-based probe. Its success, unlike past failed missions, confirms potential water ice presence and enhances India’s lunar exploration capabilities.

Overview of ChaSTE Experiment

• Chandra’s Surface Thermophysical Experiment (ChaSTE) is a pioneering scientific instrument developed by ISRO to study the thermal properties of the lunar surface.

• It is the first-ever instrument to measure in situ temperature variations on the moon’s south pole, an area of high scientific interest due to the suspected presence of water ice.

• ChaSTE is an integral part of the Vikram lander on the Chandrayaan-3 mission, which successfully landed on the lunar surface on August 23, 2023.

• The experiment involved a thermal probe that penetrated into the lunar soil and recorded temperature changes at different depths.

• Preliminary findings from ChaSTE indicate that water ice may be more abundant in the lunar polar regions than previously estimated.

• The experiment is highly relevant to GS Paper 3 (Science and Technology) for UPSC aspirants, especially in the context of India's achievements in space science.


ChaSTE’s Mechanism and Functioning

• ChaSTE is equipped with a thermal probe that contains 10 temperature sensors, each spaced 1 cm apart along its shaft.

• It uses a rotation-based deployment mechanism to enter the lunar soil, which is distinct from traditional hammering techniques used in earlier missions.

• Once inserted, the probe measures temperature gradients at different soil depths, allowing scientists to understand the thermal behaviour of the moon's surface and subsurface.

• The probe successfully penetrated up to 10 cm into the lunar regolith and continued gathering data until September 2, 2023.

• The collected data offers high-resolution thermal profiles that are vital for understanding the moon's composition and for planning future missions.

Previous Failed Missions for Similar Objectives

• Philae Lander – ESA (2014, Comet 67P):

– Carried the MUPUS instrument to measure thermal and mechanical properties of cometary soil.

– The lander bounced during landing, preventing MUPUS from deploying properly.

– As a result, it failed to collect meaningful subsurface data.

• InSight Lander – NASA (2018, Mars):

– Included HP3 (Heat Flow and Physical Properties Package) with a self-hammering probe called “The Mole”.

– Encountered low soil friction, which prevented it from digging deeper than a few centimetres, far below the target of 5 meters.

– Despite over a year of efforts, the temperature sensors failed to yield useful data.

Why ChaSTE Succeeded Where Others Failed

• ChaSTE used a rotational drilling mechanism instead of a hammering mechanism, allowing it to push into the lunar soil more effectively.

• This rotation-based design reduced the dependency on soil cohesion or friction, which were major limitations in the Philae and InSight missions.

• The stable landing of Vikram lander also ensured accurate deployment and data transmission.

• ChaSTE became the first successful mission to measure in situ lunar temperature at the south pole, overcoming all challenges that caused failures in previous missions.


Scientific and Future Implications

• ChaSTE’s success confirms the presence of water ice in the lunar south pole region, reinforcing earlier remote-sensing observations.

• These findings are crucial for future lunar missions, especially those focused on resource extraction, long-term lunar base development, and human habitation.

• The data helps scientists better understand the thermophysical properties of planetary bodies like the moon, aiding future exploration designs.

• The success of ChaSTE strengthens India’s reputation in planetary science and deep-space technology.

• The effective use of a rotational probe mechanism could influence the design of future space probes, making them more efficient in handling varied planetary soils.

• Overall, ChaSTE marks a significant step forward in India’s lunar exploration program, contributing valuable scientific insights and technological innovation.


Source: https://www.thehindu.com/sci-tech/science/chandrayaan-3-chaste-instrument-first-successful-thermal-probe-celestial-body/article69403476.ece