The Lunar Laser Ranging Instrument, which is one of the 11 payloads carried by Chandrayaan-1, has been successfully switched on. Scientists from the Indian Space Research Organisation informed that the instrument was switched on Sunday, when the spacecraft was passing over the western part of the moon’s visible hemisphere.
The preliminary assessment of the data from the LLRI by ISRO scientists indicates that the instrument’s performance is normal. LLRI sends pulses of infrared laser light towards a strip of lunar surface and detects the reflected portion of that light. With this, the instrument can accurately measure the height of the moon’s surface features.
The LLRI will be continuously kept on and it will take ten measurements per second. It provides topographical details of both the polar and equatorial regions of the moon. Detailed analysis of the data sent by the LLRI helps in understanding the internal structure of the moon as well as the way in which the celestial body evolved.
Image: An image of the moon’s surface, taken from the lunar orbit by Chandrayaan-1 spacecraft’s Terrain Mapping Camera on November 15. The picture, taken over the polar region of the moon, shows many large and numerous small craters. The bright terrain on the lower left is the rim of the 117-km wide Moretus crater.
Text: Vicky Nanjappa in Bangalore | Photograph: ISRO