History will be created when Chandrayaan-3 touches down on the Moon’s south pole on August 23, 5:47 PM IST. This is going to be unlike anything we’ve ever seen as this would be the first landing at the lunar south pole. Previous moon landings have primarily occurred in the equatorial region, with the furthest touch-down from the equator being Surveyor 7 near 40 degrees south latitude. 

Scientists from ISRO are interested in exploring the lunar poles due to the possibility of presence of water as ice molecules and hydroxyl on the lunar surface in the deep craters, which was indicated by Chandrayaan-1 in 2008.

The South Pole, in particular, is considered more promising for finding water ice due to its larger area being in permanent shadows and experience colder temperatures. The presence of water at the south pole makes it an intriguing location for studying the early solar system and Earth’s history. The South Pole-Aitken basin, a massive crater, further adds to the geological interest of the region, as it could contain material from the Moon’s deep crust and upper mantle. 

This region is highly sought-after by both space agencies and private space companies due to its water ice deposits, which have the potential to support the establishment of a future space station. The success of India’s mission in this crucial location could be a groundbreaking development and bring about significant changes in field of deep space exploration.

Ready for All Tech Challenges

Despite the scientific potential, exploring the south pole poses challenges due to difficult terrain, extremely low temperatures (below -230 degrees Celsius), lack of sunlight in certain areas, and the presence of large craters.

To address these challenges, scientists at ISRO have developed a new algorithm embedded in Chandrayaan-3’s software. Unlike Chandrayaan-2, which relied on interpreting speed from static images, the new technology in Chandrayaan-3 estimates the spacecraft’s speed in real-time as it descends towards the lunar surface. This innovative approach enhances landing safety and increases the mission’s chances of achieving a successful touchdown.

The legs of the Chandrayaan-3 lander have also been reinforced to enable it to land safely and stabilise even at a speed of 3 m/s or 10.8 km/h. This improvement is crucial to prevent a rough landing like in the case of Chandrayaan-2, where control was lost just 7.2 km away from the lunar surface. The strengthened legs increase the chances of a successful landing and reduce the risk of other potential troubles.

To enhance manoeuverability, the Chandrayaan-3 lander carries a larger fuel tank compared to its predecessor. This extra fuel allows for last-minute adjustments to the landing site, enabling the spacecraft to change course if it detects unstable surface conditions. The Chandrayaan-3 lander is equipped with solar panels on all four sides, ensuring continuous power supply even if it lands in an unfavourable direction or experiences tumbling. This design ensures that at least one or two sides of the lander will always face the Sun, providing uninterrupted solar energy.

Enhanced navigation and guidance capabilities are incorporated into Chandrayaan-3. It features new instruments, such as the Laser Doppler Velocimeter to monitor the lander’s speed and make necessary corrections. The software has been updated with improved hazard detection and avoidance algorithms, as well as upgraded navigation and guidance software. Multiple layers of redundancies are in place to ensure system reliability in case of any failures.

Extensive stress tests and experiments, including helicopter drops, have been conducted to ensure the lander’s resilience. ISRO has created various test beds to simulate lunar landing conditions, allowing comprehensive assessments of the lander’s performance and durability.

AI-Powered Moon Mission 

Chandrayaan 3 consists of the Pragyan rover similar to Chandrayaan-2 but does not have an orbiter. The Pragyan rover is equipped with advanced AI technology, enabling it to communicate with the Vikram lander. This technology also assists the rover in various tasks and operations.

Once the Pragyan rover slides off the lander and lands on the lunar surface, it will embark on a comprehensive exploration journey. One of the key capabilities of the Pragyan rover is its ability to move and land on the lunar surface. It utilises motion technology to navigate the challenging terrain and successfully reach its designated landing site. Additionally, the rover’s AI algorithm plays a crucial role in identifying traces of water and different minerals on the lunar surface. This capability allows the rover to collect valuable data and send images back to Earth for research and testing purposes.

Deep learning techniques have been used to enhance Chandrayaan-3’s autonomous capabilities. AI applications enable automatic landing, intelligent decision-making, and completely automated systems. By leveraging AI, the mission becomes more self-sufficient, independent, and capable of going beyond human limitations in identifying discoveries and transmitting data back to Earth.

Pragyan is specifically designed for a dedicated research period of 14 days on the lunar surface. During this time, the rover conducts sophisticated scientific measurements and geological studies, enabling deeper exploration and analysis of the lunar terrain. The location where Pragyan is supposed to land is chosen strategically to maximise the quality of data gathered. While it may not receive much sunlight, the rover’s primary objective is to gather extremely high-quality data, making the positioning essential for successful research.

In the broader context of space exploration, digital approaches continue to play a significant role. Data analytics is crucial for predicting, anticipating, and minimising weather hazards. AI is extensively used in developing autonomous space vehicles capable of self-diagnosis and self-repair. Virtual reality is utilised for simulated training in space missions, and digital twinning provides answers to hypothetical scenarios, which is particularly useful in relatively unexplored and unpredictable terrains.

Power-packed to the Brim

As for the scientific instruments on the Pragyan rover, it is equipped with cameras for imaging purposes. Additionally, it carries an alpha-proton X-ray spectrometer (APXS) and a laser-induced breakdown spectroscope (LIBS) for detailed analysis. The APXS instrument aims to determine the elemental composition of the lunar surface near the rover’s landing site. It achieves this by utilising X-ray fluorescence spectroscopy, where X-rays or alpha particles are used to excite the surface. Through these sophisticated techniques, the APXS can detect major rock-forming elements such as Sodium, Magnesium, Silica, Aluminium, Calcium, Iron, Titanium, as well as trace elements like Strontium, Yttrium, and Zirconium.

On the other hand, the LIBS instrument’s primary objective is to identify and measure the abundance of elements near the landing site on the lunar surface. It achieves this by firing high-powered laser pulses at various locations and analysing the radiation emitted by the decaying plasma.

Creating History, One Rocket at a Time 

The launch on July 14 at 2.35 PM IST garnered significant attention, with over 1.8 million viewers tuning in to watch the event live on ISRO’s YouTube channel. The Chandrayaan-3 spacecraft was launched aboard Launch Vehicle Mark-3 (LVM3) rocket. The rocket carried an uncrewed six-wheeled lander and rover module, configured with payloads to provide data related to the Moon’s surface, representing the aspirations of 1.4 billion Indians. 

After approximately 16 minutes, Chandrayaan-3 successfully separated from the LVM3 and entered the Earth’s orbit, marking the beginning of its fuel-efficient journey towards the Moon. If the rest of the mission unfolds as intended, India will soon join the United States, the former Soviet Union, and China as the fourth country to achieve a moon landing.

ISRO’s chairman, Sreedhara Panicker Somanath, made his first comments following the successful lift off, announcing, “Chandrayaan-3 has begun its journey towards the Moon. Our launch vehicle has put the Chandrayaan on the precise orbit around the Earth.” ISRO further tweeted that “the health of the spacecraft is normal”, indicating a positive start to the mission.

The mission aims to achieve three objectives: a safe and soft landing on the Moon’s surface, demonstrating rover abilities, and conducting in-situ scientific experiments. The launch signifies India’s second attempt at achieving a soft landing on the moon’s surface. This endeavour comes nearly four years after the Chandrayaan-2 mission faced a setback when its lander-rover pair crashed into the lunar terrain in 2019—which investigations revealed were due to malfunction in its software hardware components.

Soft landing which ISRO Chief Somanath has described as “15 minutes of terror”  is a set of critical tasks the lander must perform to land on the lunar surface. These tasks include firing engines at precise times and altitudes, utilising the right amount of fuel, conducting accurate scans of lunar surface features like hills and craters, and ultimately achieving a successful touchdown. As a result, the software and hardware of Chandrayaan-3 have been equipped with additional capabilities to address these identified problems. 

The budget of the mission has been compared with a popular Indian movie, which had a similar budget but bombed at the box office. K Sivan, then ISRO chairman, had stated in 2020 that this ambitious and domestically developed mission comes at a relatively modest cost of around Rs 615 crore. Of this amount, Rs 250 crore was designated for the lander, rover, and propulsion module, while Rs 365 crore was allocated to cover the costs of launching the mission.