Why and when was the ambitious the Mars Orbiter Mission (MOM) planned?
We had initiated a feasibility study for the Mars Orbiter Mission in August 2010, weighing the option of having a fly-by mission or an orbiter mission. We decided on the latter, under a team led by Dr V Adimurthy. In June 2011, a feasibility study report said that the PSLV-XL could be used for putting a 1,350 kg spacecraft and we could avail the next opportunity — November 2013 — for the mission. As you know, the availability of Mars Missions is dictated by the geometry between the sun, Mars and Earth and comes only once in 26 months. If we missed the November 2013 window, we would have to wait till 2016.
From drawing up the blueprint to launching the mission — everything was done in a very short time. Was this a challenge?
In Dec 2011, the Space Commission and the Cabinet approved the project. Prior to this we had consultations with present and former senior colleagues of Isro (Indian Space Research Organisation). On August 15, 2012, the prime minister announced the project. We would have to launch on November 15, if the spacecraft was to leave Earth’s orbit on the 30th. The spacecraft was ready by September 2013 but the east coast of India, where Sriharikota launchpad is located, faced a cyclone. To keep all this ready was a daunting task. We also had to do additional tests as it was an interplanetary mission — for instance, thermal balance tests to check how the spacecraft subsystems would behave under various environmental conditions. We also had to worry about radiation because the spacecraft was going to be in the Earth’s orbit for a very long time. People gave their best 24X7 to realise this mission.
What other challenges did the mission face and how did you tackle them?
When a spacecraft is so many millions of kilometres away, there is a 6-20 minute delay, one way, in signals from the spacecraft reaching the Earth and those from Earth reaching the spacecraft.
So, we had to increase the sensitivity of the spacecraft’s transmitters and use antenna of different strengths — low, high, medium — in different phases of the mission. Second, the spacecraft had to have built-in autonomy so that it could take its own decisions in the event of under-performance or failure of a sub-system, switch from the main system to the redundant system, change commands to operate payloads and safeguard the spacecraft if any major anomaly was observed so that ground controllers could analyse the problem and give directions. All this had to be done at a very short notice.
What are the technological and scientific objectives of Mars mission? And how is it doing now?
One thing we are looking for is whether life existed on Mars. The presence of methane will be an indicator of this and so we have a Mars Methane Sensor with sensitivity in the range of parts per billion. If this instrument detects methane then we need to know whether it is from a biological or geological origin. For this we have thermal infra-red sensors. Two, analyse Mars’s atmosphere.
For this there are instruments to measure the ratio of deuterium and hydrogen, and neutral particles. We also have colour cameras to take pictures and get a feel of Mars.
The spacecraft is in good health and the challenge now is to monitor it. We are also facing communication delays that we have to manage.
Very few countries have been successful with Mars exploration. Isro has so far had everything going right. Are you confident that it will reach the Mars orbit as planned on September 24, 2014?
The success rate of recent Mars Missions by Russia, America and Europe has been very low. Nearly 21 of 51 missions were failures. We had to learn from this and ensure that we didn’t repeat the mistakes and make contingency plans. The mission has three major points — one, the launch into the Earth’s orbit; two, the trans-Mars injection, and three, insertion into the Mars orbit. Two of these have been completed successfully. So we can say this mission is 85% successful .
Is the Mars Orbiter Mission the highlight of your career?
The Mars Orbiter Mission is definitely my high point.