What went wrong????????????????

The reason for early termination of Chandrayaan-1 mission happens to be miscalculation of temperature of the moon and Irso had kept the Moon orbiter’s problems tightly under wrap. Contrary to the space agency‘s explanation that Chandrayaan’s  orbit around the moon had been raised from 100km to 200km in May for a better view of the moon’s surface, it is now known that this is because of a miscalculation of temperature of the moon that led to faulty thermal protection.

Admitting this, Dr T K Alex, director, ISRO Satellite Centre, Bangalore, said, “We assumed that the temperature at 100km above the Moon’s surface would be around 75 degrees Celsius. However, it was more than 75 degrees and problems started to surface. We had to raise the orbit to 200km.”But the average day temperature on the Moon’s surface is 107 degrees Celsius, while the mean night temperature is -153 degree Celsius.

Heating problems emerge in November forcing Isro to deactivate some payloads (11 in all) and as a result some experiments have to be aborted. In early 2009, the situation improved and Chandrayaan-1 started operating normally. However, the snags resurfaced. This time with the two star sensors of Chandrayaan because of high temperature. The sensors are crucial in determining the orientation of the craft in space. The first star sensor packed up on April 26, and even the back-up sensor failed during the second week of May.

Despite the failure of the star sensors, Chandrayaan-1 transmitted excellent images including that of the solar eclipse on July 22. Also at 12.30am on August 21, it flew along with NASA’s Lunar Reconnaissance Orbiter (LRO) for four minutes to detect water ice in the north pole of the moon. But worse was to follow. At 1.30am on August 29, communication with the spacecraft snapped all of a sudden. The mission was formally called off on August 30 by ISRO. The spacecraft’s 11 scientific instruments were built in India, USA, UK, Germany, Sweden and Bulgaria.