In July 1969, I was in primary school. My heroes were cricketers — Farokh Engineer, BS Chandrasekhar and MAK Pataudi. For some of my friends, the idols were film stars. That changed overnight with the American moon landing. I put up large pictures of Neil Armstrong, Buzz Aldrin and Michael Collins, cut out from newspapers, on the walls. My father bought me a large towel with pictures of astronauts and the Moon. Half a century later, the new Indian descendants of the rocket boys – many of them women – are our new stars.
In September 2019, as the launch of Chandrayaan-2 approached, a hundred of us huddled in the cavernous lecture hall of the Inter-University Centre for Astronomy and Astrophysics (IUCAA) in Pune, watching the descent of the Vikram lander – the Pragyan rover in tow – on the lunar surface, its thrusters in full force, slowing down the free fall of the delicate component of the Chandrayaan-2 spacecraft, all 1,498 kg of it hurtling down, pulled in by the gravity of the Moon.
It had detached from the rest of the spacecraft four days ago, leaving the orbiter in its path about 100 km above the lunar surface, where it was going to spend at least seven more years, its instruments sending back crucial scientific information about the Moon, its environment and even the Sun.
We were applauding the green dot on the plot of the landing trajectory – showing the altitude and the range of the lander – till it reached about 2 km above the surface. Our spirits fell as it deviated from the expected course, and got stuck, indicating that we had lost communication. This is the phase that then Indian Space Research Organisation (ISRO) chief K Sivan described as “15 minutes of terror”. The country was crestfallen.
However, the orbiter on Chandrayaan-2 continued to operate, and after the landing dust settled, we told ourselves that the failure of the lander did not mean that the mission was unsuccessful.
We were right. The rest of the mission went on to yield unambiguous evidence of water on the Moon, with the 3-micron absorption feature in the infrared spectrum, and made important breakthroughs in surface mineralogy, composition of the ionosphere and measuring the seismic disturbances on the lunar surface. Chandrayaan-3, its successor, concentrates almost exclusively on the lander and rover. The orbiter will be mostly a propulsion module, and there will be only one experiment on the orbiter.
What went wrong in the landing last time has been analysed in great detail by several teams, based on ISRO’s own information, and images and research shared by space agencies across the world. Almost everything that can go wrong has a backup plan, and many more sensors have now been added to raise relevant alarms.
The lander will have a number of changes, including two TTC (tracking, telemetry and command) antennas, two hazard avoidance cameras, a larger fuel tank, and a single engine. There is a laser doppler velocimeter that will be used to measure the velocity of the lander during descent. The landing site has been changed to be about 100 km away, and software vastly improved to prevent the glitch that occurred during the Chandrayaan 2 heartbreak.
The Moon and Earth are supposed to be sisters – formed from the same nebula as the Sun and the rest of the inner solar system. Some models say that the composition of the Moon and the Earth should be similar, though the distribution of the components may be different. Therefore, minerals found deep in the Earth’s surface could be found near or on the surface of the Moon. Understanding the formation of the Moon can go a long way in understanding how our own planet was birthed.
Also, our knowledge of the nature of the Moon’s thin atmospheric layer, the abundance of charged particles near the surface, and the availability of water will all be very pivotal if we hope to make the Moon a base for future space exploration.
Chandrayaan-3 is a major undertaking, and has the potential to make significant scientific discoveries. The mission will provide us with new insights into the Moon’s history, composition, and potential resources. The lander and rover will conduct detailed studies of the lunar surface, including its composition, mineralogy, and geology.
The mission will also search for water ice, which could be a valuable resource for future lunar missions, as it could be used for drinking water, fuel, and other purposes. Characterising the lunar atmosphere will help us understand how the Moon’s atmosphere interacts with the solar wind and other factors. Studying the lunar seismic activity will help us grasp the Moon’s internal structure and evolution. And all of this knowledge will come together to paint a better picture of the Moon’s formation and evolution.
As for the impact on the general public, and indeed on Indian science, the mission that flies off today is an invaluable milestone.
It further demonstrates India’s technological prowess. The successful launch and landing of Chandrayaan-3 will show the world that India has the ability to undertake increasingly complex space missions. This will boost investor confidence and attract more private investment in the space sector., making way for close interaction with the industry for the long-term goal of becoming a major player in the international space industry.
Chandrayaan-3 spurred the development of new technologies, such as the indigenous propulsion module, lander module, and rover. These technologies will have applications in other areas, such as defence, transportation, and health care.
And crucially, it will inspire the next generation of scientists and engineers. The success of Chandrayaan-3 will hopefully motivate young people to pursue careers in science and engineering. This will help to ensure that India continues to be a leader in the global space race. The new heroes of the country need to be the new rocket boys and girls. And for the dreamers, it will bring the Moon much, much closer to us.
Somak Raychaudhury is vice-chancellor, Ashoka University and former director, IUCAA, Pune. The views expressed are personal
