Chandrayaan-3: Navigating the Challenges of Lunar Exploration

UPSC Prelims: GS1 (General Science) UPSC Mains: GS3 (Awareness in the fields of Space; Achievements of Indians in science & technology; Indigenization of technology and developing new technology)

I. Introduction

Background and context of Chandrayaan-3

• Chandrayaan-3 is the third lunar exploration mission by the Indian Space Research Organisation (ISRO).
• The mission is a follow-up to Chandrayaan-2, which attempted a soft landing on the Moon but failed due to a software glitch.
• Chandrayaan-3 aims to demonstrate end-to-end capability in safe landing and roving on the lunar surface.
• The mission was successfully launched on July 14, 2023, and is expected to land on the Moon’s south polar region around August 23 or 24.

Objectives of the mission

• The primary objective of Chandrayaan-3 is to place a lander and rover on the lunar surface and operate them for roughly one lunar day, or 14 Earth days.
• The mission aims to explore the lunar surface, conduct scientific experiments, and gather valuable data to enhance our understanding of the Moon’s geology and environment.
• Chandrayaan-3 will also study the Moon’s chemical makeup, investigate lunar geology and history, and perform in-situ measurements and analysis.

Importance of lunar exploration

• The Moon is a geological time capsule that preserves a record of the early geological evolution of a rocky planet, including planetary differentiation and magma ocean processes.
• Lunar exploration has advanced human knowledge in areas such as the origin and evolution of the Earth-Moon system, the geological evolution of rocky planets, and our local cosmic environment.
• The Moon’s proximity makes it a great testbed for technologies required for deep space exploration, including putting humans on Mars.
• Lunar exploration can also help assess the Moon’s potential for resources and human habitation.

II. Mission Overview

Launch and journey to the Moon

• Chandrayaan-3 was launched on July 14, 2023, from the Satish Dhawan Space Centre in Sriharikota, India.
• The spacecraft was launched into an approximately 170 by 36,500-kilometer elliptical parking orbit inclined 21.3 degrees around Earth.
• The mission uses a fuel-efficient trajectory, involving an orbit around Earth that gradually increases its apogee for around 17 days until the spacecraft performs a trans-lunar injection burn.
• Chandrayaan-3 is expected to reach lunar orbit on August 5, 2023.

Lunar orbit insertion and descent

• Once in lunar orbit, the spacecraft will gradually lower its orbital apogee until it enters a 100-kilometer circular lunar orbit.
• This process will take just under three weeks to accomplish.
• The lander is due to reach the Moon’s surface on August 23 or 24, 2023.
• The landing site is located at 69.37 degrees south latitude and 32.35 degrees east longitude, a geologically rich region embedded in a larger rocky highland.

Lander and rover components

• Chandrayaan-3 consists of a lander named Vikram and a rover named Pragyan.
• The lander and rover have a combined mass of 3,900 kilograms and are equipped with science instruments designed to deepen our understanding of the Moon’s geology and environment.
• The small rover, which weighs just 26 kilograms (57 pounds), will fly to the Moon inside the lander.
• Both vehicles are solar-powered and are expected to operate for roughly one lunar day, or 14 Earth days.

III. Comparison with Chandrayaan-2

Similarities between the two missions

• Both missions are lunar exploration missions developed by the Indian Space Research Organisation (ISRO).
• Both missions consist of a lander and a rover designed to explore the lunar surface and gather valuable data.
• The primary objective of both missions is to place a lander and rover on the lunar surface and operate them for roughly one lunar day, or 14 Earth days.

Differences between the two missions

Aspect	Chandrayaan-2	Chandrayaan-3
Components	Orbiter, Lander (Vikram), and Rover (Pragyan)	Lander (Vikram) and Rover (Pragyan)
Orbiter	Included in the mission	Utilizes the orbiter from Chandrayaan-2 for communications and terrain mapping
Propulsion Module	Present in the orbiter	Added in place of the orbiter, behaves like a communications relay satellite
Lander Engines	Five 800 Newton engines, with a centrally mounted fixed engine	Four throttle-able engines, removal of the central engine
Solar Panels	Solar panels on two sides of the lander	Solar panels on four sides of the lander
Fuel Capacity	Lesser fuel capacity	Increased fuel capacity for last-minute landing site changes
Throttling Increment	20% increment	10% increment for more gradual throttling

Lessons learned from Chandrayaan-2

• Chandrayaan-2’s lander failed to reduce its speed to the desired level in the final seconds of descent, resulting in a crash landing.
• Scientists detected problems in both the software and hardware of Chandrayaan-2.

Upgrades and improvements in Chandrayaan-3

• Chandrayaan-3’s lander and rover have been equipped with several additional capabilities in both software and hardware to avoid the issues faced by Chandrayaan-2.
• The lander has four throttle-able engines instead of five, with the removal of the central engine for improved stability.
• The lander’s solar panels have been increased from two to four sides to ensure continuous power supply.
• The fuel capacity of the lander has been increased to allow for last-minute changes in the landing site.
• The throttling increment has been improved from 20% to 10% for more gradual and precise control during the final landing phase.

IV. Technical Aspects

Launch vehicle and propulsion module

• Chandrayaan-3 was launched aboard a Geosynchronous Satellite Launch Vehicle Mark III (GSLV Mk III) rocket, which is India’s most powerful rocket to date.
• The GSLV Mk III has a three-stage design, with two solid rocket boosters, a liquid core stage, and a cryogenic upper stage.
• The propulsion module of Chandrayaan-3 is responsible for providing the necessary thrust to propel the spacecraft from Earth to the Moon.
• The propulsion module is equipped with a main engine and several smaller thrusters for altitude control and trajectory corrections.

Lander and rover design

• The lander, named Vikram, is designed to perform a soft landing on the lunar surface and deploy the rover, Pragyan.
• Vikram has four throttle-able engines for precise control during the descent and landing phase.
• The lander’s solar panels have been increased from two to four sides to ensure continuous power supply.
• The rover, Pragyan, is a small, six-wheeled vehicle weighing 26 kilograms (57 pounds) and is designed to explore the lunar surface and conduct scientific experiments.
• Pragyan is equipped with a suite of cameras and instruments for navigation, imaging, and in-situ analysis of the lunar surface.

Science instruments and experiments

• Chandrayaan-3 carries a variety of scientific instruments and experiments to study the Moon’s geology, environment, and resources.
• The lander is equipped with a seismometer to detect and analyze moonquakes, providing insights into the Moon’s internal structure and tectonic activity.
• The rover carries an Alpha Particle X-ray Spectrometer (APXS) to determine the elemental composition of lunar rocks and soil.
• A Laser-Induced Breakdown Spectroscope (LIBS) on the rover is used to analyze the chemical composition of the lunar surface at a distance.
• The rover also carries a ground-penetrating radar to study the subsurface structure and search for water ice deposits.
• In addition to these instruments, the mission aims to conduct several technology demonstrations, such as testing the performance of advanced materials and components in the harsh lunar environment.

V. Challenges and Risks

Soft landing on the lunar surface

• Achieving a soft landing on the Moon is a complex and high-risk endeavor due to factors such as the Moon’s uneven terrain, low gravity, and lack of atmosphere.
• The lander must perform a series of braking maneuvers to reduce its velocity and altitude, while simultaneously maintaining stability and avoiding obstacles on the lunar surface.
• Chandrayaan-2’s lander, Vikram, failed to achieve a soft landing due to a software glitch, highlighting the challenges involved in this critical phase of the mission.

Navigating lunar dust and uneven terrain

• The lunar surface is covered in a layer of fine dust called regolith, which can pose challenges for the rover’s mobility and the operation of its instruments.
• Lunar dust can adhere to surfaces, obstructing cameras and solar panels, and cause mechanical issues in moving parts.
• The uneven terrain of the Moon, with its craters, hills, and boulders, can also pose challenges for the rover’s navigation and stability.
• Chandrayaan-3’s rover, Pragyan, is designed to navigate this challenging environment using a combination of cameras, sensors, and a six-wheel drive system for enhanced mobility.

Deep-space communication

• Communicating with a spacecraft on the Moon requires advanced technology and infrastructure to ensure reliable and continuous communication over the vast distance between Earth and the Moon.
• Chandrayaan-3 relies on the Indian Deep Space Network (IDSN) for communication with mission control on Earth.
• The mission also utilizes the orbiter from Chandrayaan-2 as a relay satellite for communications between the lander, rover, and Earth.
• Deep-space communication is susceptible to interference from solar activity, cosmic radiation, and other factors, which can affect the quality and reliability of the communication link.

VI. Scientific Goals

Studying the Moon’s chemical makeup

• One of the primary scientific goals of Chandrayaan-3 is to study the Moon’s chemical composition, which can provide insights into its formation and evolution.
• The rover, Pragyan, is equipped with an Alpha Particle X-ray Spectrometer (APXS) to determine the elemental composition of lunar rocks and soil.
• A Laser-Induced Breakdown Spectroscope (LIBS) on the rover is used to analyze the chemical composition of the lunar surface at a distance.
• Understanding the Moon’s chemical makeup can also help assess its potential for resources, such as water ice and minerals, which could be used for future human habitation and exploration.

Investigating lunar geology and history

• Chandrayaan-3 aims to investigate the Moon’s geology and history by studying its surface features, such as craters, hills, and boulders, as well as its subsurface structure.
• The rover carries a ground-penetrating radar to study the subsurface structure and search for water ice deposits.
• By analyzing the geological features and processes on the Moon, scientists can gain a better understanding of the early geological evolution of rocky planets, including Earth.
• The mission also seeks to investigate the Moon’s tectonic activity by deploying a seismometer on the lander, which can detect and analyze moonquakes.

In-situ measurements and analysis

• In-situ measurements and analysis are crucial for obtaining accurate and detailed data about the lunar environment.
• Chandrayaan-3’s rover, Pragyan, is designed to perform in-situ measurements of the lunar surface using its suite of cameras and instruments.
• These measurements can provide valuable information about the physical properties of the lunar surface, such as its texture, hardness, and thermal properties.
• In-situ analysis can also help identify potential resources, such as water ice and minerals, which could be used for future human habitation and exploration.

VII. Global Context and Collaboration

India’s role in international lunar exploration

• India has emerged as a significant player in the global space community, with the Chandrayaan series of missions showcasing its capabilities in lunar exploration.
• Chandrayaan-1, launched in 2008, was India’s first lunar mission and contributed to the discovery of water molecules on the Moon’s surface.
• With Chandrayaan-3, India aims to demonstrate its ability to perform a soft landing and rover operations on the Moon, further solidifying its position in lunar exploration.
• India’s lunar missions have the potential to contribute valuable scientific data and technological advancements that can benefit the global community in understanding the Moon and planning future missions.

Artemis Accords and peaceful Moon exploration

• The Artemis Accords are a set of principles proposed by NASA in 2020 to guide international cooperation in lunar exploration and ensure the peaceful use of the Moon’s resources.
• The Accords emphasize transparency, interoperability, and the sharing of scientific data among participating nations.
• While India has not yet signed the Artemis Accords, its lunar missions align with the principles of peaceful exploration and international collaboration.
• India’s participation in lunar exploration can contribute to the global effort to establish a sustainable human presence on the Moon and advance scientific knowledge.

Collaboration with other countries and space agencies

• India has a history of collaborating with other countries and space agencies in its space missions, including lunar exploration.
• For instance, Chandrayaan-1 carried scientific instruments from NASA, the European Space Agency (ESA), and the Bulgarian Academy of Sciences.
• Chandrayaan-2 also involved international collaboration, with NASA providing a laser retroreflector array for the mission.
• While Chandrayaan-3 is primarily an indigenous mission, India’s commitment to sharing scientific data and collaborating with other nations can help advance global understanding of the Moon and foster international cooperation in space exploration.

VIII. Impact on India’s Space Program

Demonstrating indigenous technology

• Chandrayaan-3 showcases India’s ability to develop and execute complex lunar missions using indigenous technology.
• The mission highlights the capabilities of the Indian Space Research Organisation (ISRO) in areas such as spacecraft design, launch vehicle development, and mission planning.
• Successfully achieving a soft landing and rover operations on the Moon would further demonstrate India’s technological prowess and boost its reputation in the global space community.
• The development of indigenous technology can also lead to spin-off applications in other sectors, such as telecommunications, agriculture, and disaster management.

Growth of India’s commercial space sector

• The success of Chandrayaan-3 can stimulate the growth of India’s commercial space sector by attracting investments and fostering innovation.
• India’s cost-effective and reliable launch services, such as the Polar Satellite Launch Vehicle (PSLV) and the Geosynchronous Satellite Launch Vehicle (GSLV), have already attracted international customers.
• The demonstration of advanced capabilities in lunar exploration can open up new opportunities for India in the global space market, such as providing lunar lander and rover services for other countries and private entities.
• The growth of the commercial space sector can also create jobs, spur economic development, and promote the transfer of technology and knowledge between the public and private sectors.

Future interplanetary missions

• The experience and knowledge gained from Chandrayaan-3 can serve as a foundation for future interplanetary missions by ISRO.
• India has already demonstrated its capabilities in interplanetary exploration with the Mars Orbiter Mission (MOM), also known as Mangalyaan, which successfully entered Mars orbit in 2014.
• Building on the success of Chandrayaan-3, India can plan more ambitious missions to other planets, such as Venus and Mars, as well as missions to asteroids and other celestial bodies.
• These future missions can contribute to the global effort to explore the solar system, advance scientific knowledge, and develop new technologies for space exploration.

IX. Conclusion

Significance of Chandrayaan-3 for India and the world

• Chandrayaan-3 represents a significant milestone for India’s space program, demonstrating its capabilities in lunar exploration and the development of indigenous technology.
• The mission contributes to the global effort to explore the Moon, advancing scientific knowledge and fostering international collaboration in space exploration.
• The success of Chandrayaan-3 can stimulate the growth of India’s commercial space sector, opening up new opportunities in the global space market and promoting economic development.

Potential discoveries and advancements

• Chandrayaan-3 has the potential to make important discoveries and advancements in our understanding of the Moon’s geology, environment, and resources.
• The mission’s scientific instruments and experiments can provide valuable data on the Moon’s chemical makeup, geological history, and subsurface structure.
• These findings can contribute to the global effort to establish a sustainable human presence on the Moon and advance our knowledge of the early geological evolution of rocky planets, including Earth.

Future prospects for lunar exploration

• The experience and knowledge gained from Chandrayaan-3 can serve as a foundation for future lunar missions by India and other countries.
• Building on the success of Chandrayaan-3, India can plan more ambitious missions to other celestial bodies, such as Venus, Mars, and asteroids.
• The mission also highlights the importance of international collaboration in lunar exploration, as countries work together to share scientific data, develop new technologies, and ensure the peaceful use of the Moon’s resources.

Practice Questions

1. Analyze the technical improvements made in Chandrayaan-3 compared to Chandrayaan-2 and discuss their potential impact on the mission’s success. (250 words)