With the Chandrayaan-3 mission, India is demonstrating space capabilities that are going to give a terrific boost to its position as a major ‘cislunar economy’ player. When the success of becoming the first country to land near the lunar south pole was not enough, India announced that it had made the ~1.7-tonne lander, Vikram, hop for 40 cm from the lunar surface. If the genius tricks were not enough on the Moon, it is now announced by ISRO that the ~2-tonne propulsion module, that part of Chandrayaan-3, which transported Vikram and Pragyan to the Moon, has returned to Earth’s orbit. Simply put, the Propulsion Module, accomplished the lunar mission and has been brought back to Earth and it has now successfully travelled to-and-fro cislunar distances and for the first time carried out Trans-Earth Injection.
With the return of the Chandrayaan-3 propulsion module (C3-PM) to Earth’s orbit, ISRO has set the ball rolling on four fronts. It now has the software, planning and execution strategies to develop trajectories and manoeuvres to return from the Moon to Earth and from other planets and celestial bodies to Earth. With the return of C3-PM, it has prevented any debris on the lunar surface from the crash of the propulsion module, had it been left there for long. Why is all of this important?
The cislunar region will get enormous spacecraft traffic every passing year. These missions carried by space agencies, space companies and other stakeholders, are vying to make Earth-Moon transportation commercially feasible, prevent any harmful interference, prevent any spacecraft module from crashing onto lunar terrain – affecting the site of interest or destroying any lunar infrastructure, ensure confidence building among entities, and foster peaceful cooperation. These words, although loaded, are increasingly becoming practical.
On September 15, 2023, the International Committee on Global Navigation Satellite Systems (ICG), and the Interagency Operations Advisory Group (IOAG) put in a request to the UN Office for Outer Space Affairs (UNOOSA) to help them organise a joint multilateral workshop on cislunar positioning, navigating, timing systems in 2024-2025 timeframe. The goal of the workshop Is to ensure that the various cislunar PNT systems, which may be raised by China, Europe, India, Japan and the US soon. ICG, which works on Earth-based PNT systems, and IOAG intend to make these cislunar PNT systems interoperable, compatible and available to all lunar space users. This means lunar orbits will need to be cleared off for more strategic systems, like the PNT, and not be littered by defunct spacecraft.
Sustainable operations in cislunar space are vital not only for ISRO but also for the commercial space ecosystem in the country. The C3-PM return is not a compliance that ISRO has achieved, but an international best practice it has established. This best practice will be noticed by all. Recently the US White House published the ‘National Cislunar Science and Technology Strategy’ document, which is replete with the US’ single-minded focus on sustainable exploration and operations in cislunar space. The US very well knows that the moon will increasingly get busy and that more than demonstrating excellent science, it has become more important to set rules on the Moon for doing that excellent science. Now who would get to set rules, only the one who is economically and technologically able, and one demonstrating the best cislunar sustainable operations practices.
Taking the cislunar sustainability agenda further, there is a great engineering potential in converting the Chandrayaan-3 propulsion module into cislunar transportation systems – if ISRO is to creatively accomplish the imminent SPADEX (space docking experiment) and demonstrate propellent refilling in the orbits. Both these successes would help ISRO generate a reusable cislunar transporter that can carry spacecraft to the Moon and return defunct lunar orbiting spacecraft to the Earth orbits for repair and refurbishments. This would augur well for commercialising sustainable cislunar operations, generating revenue and ensuring constructive opportunities for the use of the Moon for the benefit of entire humankind. India must leverage this accomplishment as a crucial space diplomacy lever.