The anticipated launch of India's lunar spacecraft, Chandrayaan-3, is drawing near, and the Indian Space Research Organisation (ISRO) has unveiled fresh images of the spacecraft.
In a bold endeavour to expand humanity's understanding of the Moon and showcase India's prowess in space exploration, the Indian Space Research Organisation (ISRO) is preparing for its highly anticipated lunar mission in July.
The mission architecture of Chandrayaan-3 comprises three vital components: the Lander module (LM), the Propulsion module (PM), and the Rover. The indigenous Lander module will possess the critical ability to perform a gentle touchdown on a designated lunar site. Once safely on the Moon's surface, the Lander will deploy the Rover, which will embark on an extraordinary journey, conducting in-situ chemical analyses of the lunar terrain.
Following the trailblasing footsteps of its predecessor, Chandrayaan-2, this mission aims to demonstrate a comprehensive suite of capabilities, including a safe landing and rover mobility on the lunar surface. By doing so, India seeks to establish itself as a key player in interplanetary missions while undertaking cutting-edge scientific experiments.
Equipped with an array of scientific payloads, the Lander module of Chandrayaan-3 will revolutionise our understanding of the Moon's characteristics. Among these payloads is the Chandra's Surface Thermophysical Experiment (ChaSTE), designed to measure thermal conductivity and temperature. Additionally, the Instrument for Lunar Seismic Activity (ILSA) will provide valuable data on lunar seismicity, enabling scientists to delve deeper into the moon's geological processes. The Langmuir Probe (LP) will estimate plasma density variations, while a passive Laser Retroreflector Array from NASA will facilitate lunar laser ranging studies.
The Rover, an integral part of Chandrayaan-3, will be equipped with advanced scientific instruments to analyze the elemental composition of the lunar surface. Utilizing the Alpha Particle X-ray Spectrometer (APXS) and Laser-Induced Breakdown Spectroscope (LIBS), the Rover will provide invaluable insights into the geological makeup of the Moon's vicinity around the landing site.
To ensure the success of Chandrayaan-3, the Propulsion module will transport the Lander and Rover configuration to a lunar orbit of 100 kilometers. It will also house the Spectro-polarimetry of Habitable Planet Earth (SHAPE) payload, enabling the study of Earth from the lunar orbit by measuring spectral and polarimetric data. This additional scientific payload adds significant value to the mission's objectives.
The cutting-edge technologies incorporated into Chandrayaan-3 are at the forefront of space exploration. The Lander boasts laser and radio frequency-based altimeters for precise altitude measurements, while laser Doppler velocimeters and a lander horizontal velocity camera enable accurate speed calculations. The inclusion of laser gyro-based inertial referencing and an accelerometer package guarantees precise inertial measurements. The propulsion system features 800N throttleable liquid engines, 58N attitude thrusters, and throttleable engine control electronics, allowing for controlled maneuvering in space. The Navigation, Guidance, and Control (NGC) system, with its trajectory design and associated software elements, ensures a powered descent trajectory, while the Lander's hazard detection and avoidance capabilities mitigate potential risks. Finally, the landing leg mechanism will facilitate stable touchdown on the lunar surface, even in diverse conditions.
Extensive testing has been conducted on the Lander to ensure its readiness for the lunar environment. Integrated cold tests, where sensors and navigation performance were assessed using a helicopter as a test platform, were successfully carried out. Likewise, integrated hot tests, utilising tower cranes as test platforms, confirmed the closed-loop performance of the sensors, actuators and NGC. Lander Leg mechanism have been tested on a lunar simulant test bed simulating different touch down conditions.
The outer layer of polyimide material adorning the satellite exhibits a striking yellowish-gold hue, creating an impression as if it is cloaked in gold. Multi-layer insulation, employed for thermal control purposes, serves to safeguard the spacecraft's sensitive onboard instruments from the harsh and fluctuating temperatures of the space environment.