Chandrayaan-I stopped transmitting signals to ISRO at 1.30am on August 29, 2009 and since then we all have been wondering about the reasons for its failure. ISRO now has given some real clues regarding its failure, the primary being the heating problems on the aircraft, which first surfaced as early as Nov 25, 2008.
While the reasons behind ISRO hiding the actual reasons so far is still unclear, it is now confirmed that ISRO miscalculated Moon’s temperature that led to faulty thermal protections.
Heat was the primary reason behind ISO raising Chandrayaan-I’s moon orbit from 100 kms to 200 kms in May, 2009. ISRO had earlier said that this was done to get a better view of Moon’s surface and help it in further studies.
The problem first surfaced in Nov 25 itself because of which some experiments could not be carried out, as some of the payloads were deactivated by ISRO. Then by April 26, two sensors responsible for determining the orientation of Chandrayaan I space craft failed. However, Chandrayaan I kept transmitting some excellent images back to the earth station including that of the solar eclipse on July 22 and only stopped on August 29, 2009, when Chandrayaan completely stopped communicating with the control room.
ISRO does admit that India’s moon mission Chandrayaan I has completed almost 95% of its objectives.
Some of the key successes of the moon mission are:
1. Nov 8, 2008: In its very first attempt, successful entry into the lunar orbit at 4.51 pm. Considering that all US/former Soviet Union’s lunar missions had a 30% failure rate, this was a big achievement.
2. Nov 14, 2008: Moon Impact Probe detached from the main Chandrayan I spacecraft and crash landed successfully near the Shackleton Crater on the south pole of the moon.
3. Aug 21, 2009: Chandrayaan flew along NASA’s Lunar Reconnaissance Orbiter for four minutes and both conducted an experiment to detect water ice on the lunar surface.
4. The moon mission captured the images of the landing site of Apollo 15 (1971), dismissing theories that the US manned mission was a hoax.
5. It transmitted 535 images every day, some images had a resolution up to five metres!
The Indian Space Research Organization is now gearing up for the launch of Chandrayaan-2, which is expected to be launched in 2012-13. Learning from the mistakes in the first version, ISRO has said that Chandrayaan-2′s thermal design will be strengthened to withstand more than 100 degrees Celsius.
ISRO is also working towards an unmanned flight to Mars between 2013 and 2015.