An abrupt end to the odyssey.

Chandrayaan- I's two- year mission ends in 10 months

INDIA'S space ambitions suffered a major setback on Saturday when one of its showcase projects, Chandrayaan- 1, came to an abrupt end.

The country's maiden moon spacecraft lost all contact with the earth. It was designed to stay in the lunar orbit for two years, but its mission has come to an end within ten months of its launch in October last year.

Radio contact with the spacecraft was abruptly lost at 1.30 am, an Indian Space Research Organisation ( ISRO) spokesperson said on Saturday.

Then it has been a communication " blackout'. " We cannot send or receive any data," ISRO spokesperson S. Satish said. Scientists explained that such blackouts of satellites launched by other agencies had meant the end of those projects.

Satellites functions and course are corrected by radio signals sent from the ISRO Telemetry, Tracking and Command Network ( ISTRAC) through a giant antenna at Byalalu. So a radio blackout could, in effect, mean Chandrayaan- 1 could lose its orbit altogether. A lost satellite could orbit around the moon on its momentum for a while or crash onto the lunar surface.

At the ISTRAC, that controls the spacecraft movement, director S. K. Shivakumar confirmed that radio contact has been lost but declined to elaborate further.

" The Deep Space Network at Byalalu village near Bangalore received data from Chandrayaan- 1 during the previous orbit up to 12.25 am," said an ISRO release. But it was quiet about the latest orbit.

Since May, ISRO has been engaged in a damage control exercise on the mission front. It had raised the orbit of the spacecraft from its original 100 km altitude above the moon to 200 km on May 19. The rationale offered at a scientific forum at that time was that most of the mission objectives had been completed and ISRO wanted test flight dynamics in view of future missions.

In July, ISRO chairman Madhavan Nair had acknowledged that a vital star sensor on board the spacecraft that orients its position was irreparably damaged, making it difficult for the spacecraft to navigate.

Acknowledging that trouble was brewing for quite some time, he had said high temperature or radiation reflected from the moon's surface could have actually damaged the entire spacecraft and raising the orbit saved it. The talk about test ' flight dynamics ended.

After failure of two such sensors, ISRO has been using gyroscopes -- mechanical devices that required constant correction on course. The space agency, however, reiterated that Chandrayaan- 1 would complete its two- year mission.

A month into orbit after its October 2008 launch, ISRO scientists had pointed out that high solar radiation was making the heat unbearable for the spacecraft and threatening its highly sensitive instruments. Some instruments had to be switched off to prevent overheating, as the gadgets themselves could generate their own heat.

Based on data from the last recorded, orbit scientists are trying to ascertain what would have gone wrong. " It could have been an instrument failure or excess temperature failing the system," Satish said.

Project director Mylswamy Annadurai was more direct in a statement he issued: " The mission is definitely over. We have lost contact with the spacecraft." However, he reiterated the ISRO line: " It has done its job technically... 100 per cent.

Scientifically also, it has done almost 90- 95 percent of its job." Chandrayaan- I was launched from Satish Dhawan Space Centre Sriharikota on October 22, 2008. It has completed 312 days in orbit, going around the moon 3,400 times. It mapped the moon for a three- dimensional atlas, studied its radiation, gravitation and magnetic environments, took pictures of lunar craters and probed for water. Its contributions could throw light to the evolution of earth's lone satellite.

While a massive volume of data is being analysed at the Indian Space Science Data Centre ( ISSDC), ISRO has announced a meeting of collaborating scientists, including from the US and European spaces agencies, next month. Making sense of the data could take months. Already, ISRO scientists and collaborators have published papers based on Chandrayaan- 1 data.

Even after its troubles, Chandrayaan- 1 had continued to beam images and completed a joint probe with a US National Aerospace and Space Agency ( NASA) spacecraft on August 21. The probe with NASA's Lunar Reconnaissance Orbiter looked for ice in a permanently shadowed crater near the north pole of the moon.

ISRO scientists said some of the lessons from Chandrayaan- 1, especially the heat vulnerability of the payload and sensors, have offered valuable lessons for the second mission slated for 2012.

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