The acronym for HYSI is Hyper-Spectral Imager. The HYSI camera is used in Chandrayaan-1 Probe. The main objective of the Chandrayaan-1 HYSI is to conduct mineralogical mapping of the lunar surface. The data collected from this instrument is used for our Indian researchers to conduct test and it also used to improve the available information on mineral composition on Moon.
The HYSI has capability of mapping the lunar surface in 64 colors. The wedge filter in the HYSI camera is used to split the light into 64 colors. The spectral bands is mapped by using an Active Pixel Sensor (APS) with built in digitizer. To reduce the weight and to get compactness of the system the wedge filter is used in HYSI camera.
The HYSI is able to capture the color images which is used to detect the difference between the minerals found on the moon surface. Its payload mass is upto 4kg and its size is 275 mm x 255 mm x 205 mm.
Difference between HYSI and M3:
ISRO’s HYSI Space Applications Centre (SAC) and NASA's Moon Mineral Mapper(M3) both are used to investigate the mineralogical composition in Moon surface.
But NASA's M3 can analyze the wavelength in the range of 0.4-0.3 microns while ISRO's HYSI can analyze upto 0.43 microns to 0.96 microns. It can analyze the wave lengths from visible to near infrared spectrum.