India's maiden moon probe Chandrayaan-I has developed a malfunction that puts some experiments in jeopardy and raises questions on completion of the mission that was intended to last two years.
"Unfortunately, during the last month we have lost a vital sensor --- the star sensor," Indian Space Research Organisation (ISRO) Chairman G Madhavan Nair said.
He said space scientists had tried to work around the problem and patched two other instruments to help manoeuvre the spacecraft to the desired locations.
"We are not sure how long we will be able to sustain it. The life of Chandrayaan-I designed for two years may be reduced," ISRO spokesman S Satish said. Chandrayaan was launched on October 22 last year.
Nair said that in the last eight months of the mission, "we have collected almost all the data that we wanted" and that most of its objectives have already been completed.
The problem would mean that some of the 10 experiments onboard would have to be replanned and at least one involving the Lunar Laser Ranging Instrument (LLRI) being abandoned.
The LLRI was designed to measure altitude variations within five-metre accuracy and operate at a 100-km altitude, a distance at which the spacecraft was to orbit the moon during its two-year mission period.
ISRO had raised the orbit of Chandrayaan-I to 200 kms on May 19.
Referring to the efforts to keep Chandrayaan-1 going, Nair said gyroscopes as well as an antenna have been used to allow the craft to find a direction.
"We are able to continue the functions as in the past and there is no major issue as of now," the ISRO chief added.
"I think in the last eight months of its operation, we have collected almost all the data that we wanted. In fact now what we are going to get is basically a kind of redundant data and more of a cross checking and things like that. So that way, most of the mission's objectives are already complete," Nair said.
Lauding the scientist for overcoming the failure, he said it was their imagination, the promptness of action and the type of solution which were unique.
