This Article is From Jul 17, 2009

Chandrayaan crippled, but working

Chandrayaan crippled, but working

AP image

New Delhi:

India's maiden mission to the moon, associated with so much national prestige, has run into rough weather. It has had a severe malfunction with scientists fearing that the mission may well have to be terminated halfway. In a global exclusive, our Science Editor Pallava Bagla sat down with Dr G Madhavan Nair, chairman of the Indian Space Research Organisation to find out more details.

NDTV: Has there been a malfunction on the Chandrayaan?

G Madhavan Nair: Space missions are complex. There are instances of problems. We are also not spared. The first thing we encountered when it was put into 100km orbit... it simply reached a stage of thermal runaway. The entire spacecraft would have simply baked and lost. That was the scenario after a month of the launch. Fortunately our mission team worked out a strategy by which it was oriented in the right direction. It had reached a stage where many of the electronic equipment would have failed. Fortunately we were able to energise the redundant units to keep it live all this time. This has been going on since quite some time but unfortunately during the last one month, we have lost one vital sensor - the star sensor - like in the old days when mariners looked at the stars to fix the direction, we have an onboard equipment which is doing this, which required for precise pointing We were really worried with the loss of that. Normally the entire mission could be lost, but to the credit of the ISRO scientific team, they have worked out a very innovative way of overcoming this.

NDTV: Can we call this jugaad technology?

G Madhavan Nair: I would say that it is the imagination and the promptness of action and also the type of solutions that we find are very unique. We don't have a luxurious situation where if something fails we can go for another mission quickly. So we try to see that these missions are very keenly attended to and nothing is left to chance.

So, what has really gone wrong with the 400 crore Chandrayaan-I satellite? Is there a solution to this problem? Are the scientific objectives likely to be achieved?

Launched last October, the Chandrayaan performed excellently till it ran into problems a month back. On reaching the moon it even planted India's flag on the lunar surface and brought back stunning images of the moon.

According to the Indian space agency, a month ago a prime instrument developed a glitch. The device called a Star Sensor, literally the eye of Chandrayaan, went blind. This is used to manoeuvre the spacecraft with this malfunction; essentially Chandrayaan's pointing accuracy has been compromised. It is orbiting the moon, all its other instruments are working well, but today it cannot be commanded with accuracy - where to look on the moon's surface.

The first inkling that something was wrong with the mission came in May this year, when ISRO decided to raise the orbit of the spacecraft to 200km above the moon from the 100km orbit it was mandated to be in. It was not disclosed that something was really amiss, in a statement then ISRO said this was done `after successful completion of all the major mission objectives'. Indeed, according to the scientific team a lot of data has really been collected.

What has been compromised:

  • Some of the scientific instruments may not be able to gather all the data, especially the European lunar resource mappers
  • India's instrument meant to estimate lunar heights may not get enough return signal
  • The resolution of some on-board cameras may be compromised
  • It may not be able to complete its full life of two years

Earlier this year, Chandrayaan had to be literally sent on a summer vacation, as it was getting overheated in the lunar summer. Suitable corrections helped tide over the problem.

Is everything over?

No, say scientists from ISRO. Some innovative techniques which can only be called Indian Jugaad have been found to keep manoeuvring the spacecraft. Other sensors on the spacecraft, used to measure temperature and its unidirectional antenna, are helping point the spacecraft which is almost 400,000km away.

Meanwhile, the spacecraft continues to beam back stunning images of the moon, even in its crippled state.

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