Chandrayaan-1, India’s first mission to Moon, was launched successfully on October 22, 2008 from SDSC SHAR, Sriharikota. The spacecraft was orbiting around the Moon at a height of 100 km from the lunar surface for chemical, mineralogical and photo-geologic mapping of the Moon. The spacecraft carries 11 scientific instruments built in India, USA, UK, Germany, Sweden and Bulgaria. After the successful completion of all the major mission objectives, the orbit has been raised to 200 km during May 2009.
It had a definite set of goals. These were:
- To further enhance the already acquired knowledge about the Moon
- To achieve further progress technologically. This meant to further increase India’s capacity to build more efficient rockets and satellites, especially through miniaturisation
- To provide challenging opportunities to young scientists of India to do research in new and exciting areas like the study of planets (indeed, Moon is large enough to qualify as a planet!)
How these well meant goals were to be achieved?
For that, ISRO had a set of scientific objectives. These were:
- To photograph the surface of the Moon in such a way that length, breadth and height of the surface features of the moon can be found out accurately. This is called 3D imaging and can lead to the preparation of a more accurate map of the Moon
- To prepare an atlas of the Moon, accurately showing the way in which various elements and minerals are distributed over its surface
- To prepare a map of the Moon that shows different geological areas there clearly
These were highly challenging tasks indeed. But, they were attempted in a methodical way using scientific instruments carried by Chandrayaan-1 spacecraft. The instruments (or ‘payloads’ as scientists call them) include cameras taking black and white 3D pictures or colour pictures, a LASER instrument to accurately measure the height of Moon’s surface features, spectrometers to accurately find out the availability of various radioactive and non-radioactive elements as well as various minerals, and a radar to find out whether water ice really exists in the polar areas of the Moon.