Today is the day a year ago when Chandrayaan I India's First Mission to Moon was launched from Satish Dhawan Space Centre (SHAR),Sriharikota, Nellore District of Andhra Pradesh.Today Planetary Society, India celebrates the first anniversary of this historic launch.
Commemorating this great occasion society reaffirms it dedication for promotion of space sciences. As part of the celebrations society organized "Journey to Moon and Beyond" a special awareness session involving school teachers.
Grand Salute offered :Marking the success of Chandrayaan I historic revealings of Water on Moon and many new truths to be unraveled from its data.Later in the evening Members of the society looking at Moon offered Grand Salute in honor of the spacecraft which is still in orbit though not in contact with earthlings.
We here present brief overview of India's Journey to Moon as Pradeep Mohandas uncovers :
The Beginning
1. Chandrayaan-I came out of a proposal provided by K Kasturirangan, former ISRO Chairman, who said that the Indian PSLV is capable of placing a small satellite in lunar orbit by 2008 in 1999. The plan was approved seperately by Indian scientists under the Indian Academy of Sciences and Astronautical Society of India.
2. Chandrayaan-I initially planned to carry 4 Indian instruments only. President A P J Abdul Kalam suggested the idea of an impactor to ensure that India registered its presence on the Moon and should offer 1 place for a foreign payload. India's fifth contribution, Moon Impact Probe (MIP) was born out of this suggestion. Announcement of
Opportunity for foreign payloads was solicited and returned 26 proposals from various countries. 6 were selected by ISRO.
3. The team developing Chandrayaan-I faced several problems: geographically seperated work centres, different work cultures and methodology, different levels of development, international laws, bureaucratic red tape, technical challenges, balancing budget
constraints etc.
4. The team offered a free ride for the 6 foreign payloads. The only requirement was that the data collected be shared. This data is valuable and could not have been easily accessed from a mission like LRO which is completely US run.
5. ISRO completed the development of additional requirements – Indian Space Science Data Center, Indian Deep Space Network and the improvised version of PSLV - PSLV-XL on time and within budget.
6. It also kept the promise given in 1999 for a launch of a small satellite carrying atleast 4 instruments orbited by PSLV by the year 2008.
The Journey to the Moon
1. Five Earth burns and three lunar burns took Chandrayaan-I to lunar orbit on November 8, 2009. It became the first Indian object to go into deep space.
2. PSLV-XL and the improved Liquid Apogee Motor (LAM) performed well to take Chandrayaan-I to desired orbit.
3. On its way to the Moon, after the Terrain Mapping Camera (TMC) was switched on, it took India's first Earth from Deep Space images of the Eastern Hemisphere.
4. All instruments on-board were switched on during the commissioning phase of the spacecraft and tested. SARA was the last instrument to be turned on in December.
Heating up
1. Chandrayaan-I faced thermal problems starting in November because of the extreme heat it faced in lunar orbit.
2. Scientists say it could be because the value of temperature taken during the design phase may have been lower than expected. This was taken as 75 degrees C. This, it is believed was not sufficient.
3. Scientists controlled the temperature by turning off various instruments and turning them on only when needed. Instruments give off heat much like a desktop computer does. It was believed that controlling the internal temperature could provide some sense of
thermal stability for the spacecraft and it worked.
Impact!
1. The MIP seperated from Chandrayaan-I for impact at 8:01 pm IST on November 14, 2008.
2. 20 minutes later, it impacted on the surface of the Moon and India became the fourth country to wilfully impact the Moon.
3. The impact was dedicated to India's first Prime Minister, Jawaharlal Nehru who supported the Indian Space Programme and to the children of the country as the country celebrates Children's Day on this day.
4. ISRO later said that its on board spectrometer had also detected signs of water on the Moon.
5. MIP impacted close to the Shackleton crater close to the South Pole of the Moon.
Pointing Problems
1. In April 2009, it is believed that some of the thermal problems faced by Chandrayaan-I led to the failure of the star sensor and the power bus.
2. The problem in the star sensor meant the spacecraft could not be properly pointed to the lunar surface. This led to using the back up system.
3. The back up system involved using gyroscopes, tracking certain features on the lunar surface and using Sun and Earth sensors to work out where the spacecraft was pointing at. The spacecraft was thus fixed.
4. The power bus problem affected the internal power supply system had problems. This is believed to have led to Chandrayaan-I's end as a result of loss of power to the antenna which was used to keep in touch with Chandrayaan-I.
Going Up!
1. On May 20, 2009 ISRO raised the orbit of Chandrayaan-I to 200 km circular polar orbit.
2. ISRO stated that all mission objectives at 100 kms were achieved. It said later that problems with the star sensor contributed to the decision.
3. Being at a higer orbit meant that the spacecraft could be better controlled from Earth. It meant some loss in the resolution (clarity) of data but enabled wider swath coverage.
Contact Lost
1. On August 29, 2009 ISRO called off the Chandrayaan-I mission after radio contact with the spacecraft was lost.
2. It is believed that the antenna could not be supplied with sufficient power to relay messages to Earth and led to the loss of the antenna.
3. This led to the failure of being able to track and send commands to the spacecraft. Hence, the spacecraft was lost.
Munching the Data
1. The technical mission ended on August 29, 2009 and provided lots of data for scientists to work on. This would be useful for future missions to the Moon.
2. The scientific mission began as soon as the spacecraft started sending back data and is now continuing.
3. Munching the Data to convert it into a form in which humans can understand and then interpret what the data is saying will provide insights into the mysteries of the Moon.
4. Data from various instruments is now being continued and ISRO expects data to get results over the next 3 years.
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