The Indian Space Research Organisation Chandrayaan-1 spacecraft was launched on the 22nd of October 2008. It spent nine months in a 100 km circular orbit around the Moon before communication was lost. During this time it surveyed the around 15 percent of the lunar surface providing a map of chemical characteristics and 3-dimensional topography. The spacecraft carried a number of instruments including a terrain mapping camera, infrared spectrometers, and the Chandrayaan-1 X-ray Spectrometer (C1XS). The C1XS instrument consisted of 24 e2v technologies CCD54 swept-charge device silicon X-ray detectors arranged in 6 modules that will carried out high quality X-ray spectroscopic mapping of the Moon using the technique of X-ray fluorescence in the energy range 0.5-10 keV.
The CEI was involved in performing the proton radiation damage assessment for the CCD54 devices recommending instrument shielding, operating temperature and operating potentials. The pre-flight characterisation of the 14 modules available for flight selection was also conducted recommending ten modules suitable for use in the instrument. The ESA space environment information system (SPENVIS) software was utilised to estimate the worse case end of life 10 MeV equivalent proton fluence, which was used to irradiate a number of CCD54 devices to investigate their post irradiation performance. The CEI continues to be involved in the instrument in an advisory role on the observed radiation effects to the CCD54 devices.