Why Chandrayaan-3 stands out from all other moon missions

We are just hours away from the launch of Chandrayaan-3. The moon mission is scheduled for take-off on 14 July, and preparations are in final gear to ensure it is safe and successful. India Space Research Organisation (ISRO) said that the launch will take place at 2:35 pm from Satish Dhawan Space Centre in Sriharikota, Andhra Pradesh and if all things go as planned, it will land on 23 August. In anticipation of the big moment, on 5 July, ISRO successfully integrated the Chandrayaan-3 spacecraft with the launch vehicle, Launch Vehicle Mark-III (LVM3), at the space centre – a significant moment, as the LVM3 is the biggest rocket ever built in India. **Also read: Chandrayaan-3 integrates with launch vehicle: Why is this significant?** Chandrayaan-3 is a follow-on mission to Chandrayaan-2 to demonstrate end-to-end capability in safe landing and roving on the lunar surface. The mission aims to explore the Moon’s surface, particularly areas that have been deprived of sunlight for billions of years. As the countdown begins, ISRO has also said that Chandrayaan-3 will land near the Moon’s South Pole. But why is this important? Is it more difficult to do so? We give you all the answers. A first in the world? While there have been several Moon landings, Chandrayaan-3 will be the first to land on the South Pole of the Moon. All other spacecraft which have landed on the moon have landed in the equatorial region, a few degree latitude north or south of the lunar equator. An Indian Express report states that the furthest any spacecraft has gone from the equator was Surveyor 7, launched by NASA, which made a moon landing way back on 10 January 1968. This spacecraft landed near 40 degrees south latitude. In April 2019, Israel rocketed towards the moon, attempting a landing on the South Pole, but it crashed. Even India’s Chandrayaan-2, launched in 2019, was to land on the South Pole of the moon, but the lander carrying the rover crashed into the Moon during the final moments. It was later revealed that the crash was due to a software error. ISRO chief Sreedhara Somanath has said that changes to the software and hardware of the Chandrayaan-3 mission, especially for the lander thrusters, have been made. Additionally, ISRO has developed improved soft-landing sequences and the lander has four thruster engines instead of five, sturdier legs and larger solar panels, and will carry more fuel to ensure success this time over. Even China’s Chang’e 4 in 2019, which became the first spacecraft to land on the far side of the moon (the side that does not face the earth), landed near the 45-degree latitude. NASA’s Artemis III, scheduled for a 2025 launch, is also attempting to explore the region near the lunar South Pole. [caption id=“attachment_12848512” align=“alignnone” width=“640”] Chandrayaan-3 spacecraft at the Satish Dhawan Space Station ahead of its launch, in Sriharikota. PTI[/caption] But why the moon’s South Pole? The lunar South Pole has long held the interest of scientists and space experts. NASA has, in the past, said, “Extreme, contrasting conditions make it a challenging location for Earthlings to land, live, and work, but the region’s unique characteristics hold promise for unprecedented deep space scientific discoveries that could help us learn about our place in the universe and venture farther into the solar system.” Experts note that there is a possibility of the presence of water at the South Pole. Girish Linganna, space and aerospace expert told The Week that Water ice has been detected at both poles of the Moon. The South Pole has more area in permanent shadow and colder temperatures, so it is thought to have more water ice. Moreover, the South Pole witnesses extremely cold temperatures; this means that anything trapped here would remain frozen in time, without undergoing much change. The rocks and soil in this region could therefore provide clues to early solar system. Linganna, further explained, that the South Pole is located in the South Pole-Aitken basin, which is a huge crater. “This makes the South Pole a geologically interesting place because it is possible that there is material from the deep crust and upper mantle of the Moon on or near the surface. The South Pole is also a more promising place to look for ice than the North Pole,” he was quoted as telling The Week. However, exploration of the South Pole is not easy. The terrain is difficult and the low temperatures are also a problem. Several parts of the South Pole lie in a completely dark region where sunlight doesn’t penetrate. Also, temperatures fall to as low as below 230 degrees Celsius. The lack of sunlight and extremely low temperatures create difficulty in the operation of instruments. There are also large craters on the South Pole, some a few centimetres in size, while some are as large as several thousand kilometres. Even a former ISRO chief had highlighted several concerns about landing on the South Pole of the lunar surface during the Chandrayaan-2 mission, saying there would be “15 minutes of terror” for the space agency before the touchdown. **Also read: Japanese company’s bid for moon landing fails: A look at other private players and their missions** What do we know about Chandrayaan-3 so far? Chandrayaan-3 is the third instalment of the Chandrayaan series and India’s second attempt to achieve a soft landing on the Moon’s surface. Only three countries – the United States, Russia and China – have successfully landed spacecraft on the airless lunar surface. Unlike its predecessor, Chandrayaan-3 does not have an orbiter, and its propulsion module is more similar to a communications satellite. However, it does maintain the same mission architecture while incorporating crucial modifications. In doing so, Chandrayaan-3 will rectify past shortcomings and achieve a successful lunar landing. [caption id=“attachment_12848462” align=“alignnone” width=“640”] Graphic: Pranay Bhardwaj[/caption] According to ISRO, the propulsion module will carry the lander and the rover to lunar orbit and the lander-rover pair will attempt to land on the Moon, carrying six scientific instruments to gather data from the surface. The rover is equipped with a laser-induced breakdown spectroscope and an alpha particle X-ray spectrometer to study the chemical composition of the surface of the Moon. A Business Standard report pegs the cost of Chandrayaan-3 to be Rs 615 crore. Also, the Chandrayaan-3 mission is only meant to last for a half lunar day, which is roughly equal to 14 Earth days. Tomas Hrozensky at the European Space Policy Institute in Vienna was quoted as telling Nature.com, “If successful, India’s Moon landing will have important technological and geopolitical dimensions.” Let’s hope that third time’s the charm for India and ISRO makes history on 14 July. With inputs from agencies