‘IN ROCKET SCIENCE, THERE ARE ALWAYS UNKNOWN UNKNOWNS
ISRO chairperson DR KAILASAVADIVOO SIVAN spoke to Group Editorial Director RAJ CHENGAPPA on the Chandrayaan 2 mission and whether it had impacted the space department’s future plans. Excerpts:
Q. What is the significance of finding the lander on the moon’s surface?
A. There is no significance, we are unable to communicate with it. We have located it, that’s all.
Q. What do the photographs from the orbiter show?
A. It has not soft landed. All we know is that there is an object on the moon’s surface that was not there when we attempted to land Vikram. We know it’s not a new crater; so, by deduction, we know it is Vikram. We cannot say anything beyond that.
Q. Have you determined why communication with Vikram failed?
A. The analysis is going on, I can’t say anything more now.
Q. Was it a propulsion or control problem?
A. We are analysing the data and we are still trying to understand what the problem is. Q. Did you anticipate there would be a problem when you earlier talked of the descent being ‘15 minutes of terror’? A. These are new technologies that we have developed and we were demonstrating them for the first time in flight. Hence, the 15 minutes of terror.
Q. When did you sense that something was wrong? A. Once we lost communication, we knew.
Q. What did you tell the prime minister when it happened? A. I told him what happened. He said, don’t worry, don’t get disheartened.
Q. Next day you broke down when he was leaving and he hugged you. How did it make you feel?
A. Apart from being our national leader, he is our boss too (the space department comes under the PMO). I became emotional because we could not meet his expectations. He immediately consoled me and I felt relieved. The prime minister of the country hugging you gives you a feeling of inspiration. It’s given me the mental strength for the tasks that lie ahead.
Q. Despite the setback, you claimed that the Chandrayaan 2 mission was 95 per cent successful...
A. The mission had two main objectives. One is the science mission we are conducting using the instruments on the orbiter. The other is the technology demonstration for the landing. On the science front, everything has gone well. We have a powerful dual band synthetic aperture in the orbiter where we can penetrate 10 metres below the surface. It will give us wonderful information about water, minerals and other things present on the lunar surface and below. We also have high resolution cameras and advanced infra-red imaging spectrometers that will enable us to collect fantastic data for science. The other thing is that the orbiter’s
life, which was designed for one year, will now go on for seven and a half years. We have done this by optimising our fuel strategy after the launch vehicle gave us extra performance. So in the science part we have got more than we wanted.
Q. What about the technology demonstration part?
A. Well, there are lots of new technologies we have developed. Like throttle-able engine, sensors and navigation and guidance systems. Of the 15 minutes in the descent phase, except for the last two minutes, we demonstrated all the technologies. It’s true we couldn’t achieve the soft landing, but all considered, this mission has been more than 95 per cent successful.
Q. What next? Will there be a Chandrayaan 3?
A. That we will decide only after the outcome of our analysis. We have to find out what really happened, only then can we talk about the future.
Q. Will this slow down ISRO’s space exploration programmes, including the manned mission?
A. Everything will go on as planned. Not only planetary exploration, but also Gaganyaan (manned mission to space) apart from newer developments. There is a lot more challenging work to do and more complex missions. So rather than worry about what happened in the past, we are determined to do the work we have set out to do.
Q. What lessons have you learnt from this setback?
A. We always say space is unforgiving. Also, in rocket science, there are always unknown unknowns. This setback was one among them. It’s part of space programmes—you can have 12 successful launches and then one may fail. In space, till the objective is achieved, whether we are using a new system or an old one, we cannot say it is done.