The Indian Space Research Organisation (ISRO) came very close to pulling off yet another spectacular first-attempt success by landing a spacecraft on the surface of the Moon. The spirit of attempting to leapfrog from orbiting a spacecraft around the Moon a decade ago to landing near one of its poles within a span of just one mission by ISRO is laudable. The lessons it will glean from the problems that occurred only moments before the lander’s touchdown will empower it to be better prepared for the next attempt.
Regardless of the last-minute glitch, Chandrayaan 2 showcases how having a strong hold on technological building blocks is important to achieve new feats in space exploration. To put this in perspective, ISRO established its prowess in launching, spacecraft guidance, navigation, control and communication with Chandrayaan 1, and the follow-up mission attempted to take this one step forward by adding lander/rover separation, soft-landing and rover-lander-spacecraft-Earth communication chain to the mix.
The following are some features ISRO needs to consider investing in so that we have a clear technological foundation to conduct missions that are logical extensions of Chandrayaan 2.
Making things bigger, better
Rockets – Space exploration missions are all about scientific outcomes. More often than not, to do good science, you need payloads that are more sensitive, have more room, are consequently heavier, have more power and sport broader communications abilities. To accommodate these features, you then need a larger spacecraft, a larger lander and a larger rover. This in turn means that you need a larger rocket to carry the stack into space.
ISRO is currently working on increasing the GSLV’s payload capacity. Any substantial increase in this number will directly affect the potential quality of the science payloads that can be delivered to the Moon’s surface in future missions.
Power sources – The Pragyan rover on the Chandrayaan 2 mission intended to operate on solar power. It was slated to traverse 500 meters on the lunar surface at the rate of 1 cm per second and attempt to perform chemical analyses of lunar soil. The rover’s mission timeline was set to only one lunar day, which corresponds to 14 Earth days.
ISRO scientists might have attempted to temporarily switch off the rover during the lunar night and revive it at the start of the next lunar day to continue operations. However, on a long-duration mission with more complex payloads, ISRO will need to adopt technologies that will allow the rover’s batteries to survive the extreme cold of a night on the Moon.
This means India will need to adopt radioisotope thermoelectric generators and radioisotope heater units – and technologies derived therefrom – for future rover missions. This could arise and mature out of a collaboration between ISRO and the Bhabha Atomic Research Centre, Mumbai. Adopting such technologies would then allow ISRO to move beyond Mars and confidently explore other niches, such as asteroids and the moons of other planets.
Sample-return – Any rover sent to the surface of the Moon can carry only a small number of experiments, and scientists often make difficult decisions about which instruments to include towards achieving the best possible research outcomes. This said, being able to obtain a physical sample from the surface of a planetary body and transporting it to Earth can dramatically improve the kinds and sophistication of tests scientists can run.
The Moon is the most logical destination to establish the technology for such sample returns because it is close. So planners of the next Moon mission could consider including sample-return technologies, which would be a fitting next step after Chandrayaan 2.
Technological developments go hand in hand with science outcomes, and advancing technology on only one or two fronts, such as bigger rockets alone, can not add up to having the ability to perform more complex missions.
Beyond Chandrayaan 2, ISRO must review its technological capabilities roadmap to look at all the baseline systems that the organisation will need to invest in so that, in future, it may find itself prepared to take on more complex objectives that lead to greater scientific outcomes. The government should also consider increasing its R&D expenditure for such longer-term technological maturity cycles so that this habit of undertaking bigger and better missions can continue.
Narayan Prasad is the host of the NewSpace India podcast, India’s only talk show focused on space activities.