Bangalore, Nov 16: The Lunar Laser Ranging
Instrument (LLRI), one of the 11 payloads carried by the
Chandrayaan-1 spacecraft, was successfully turned on Sunday
when it was passing over the western part of Moon's visible
hemisphere.
Preliminary assessment of data from the LLRI by
scientists indicates that the instrument's performance is
normal, an ISRO statement said.
The 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 very accurately
measure the height of Moon's surface features.
The instrument will be continuously kept on and is
taking 10 measurements per second on both day and night sides
of the Moon. It is also providing topographical details of
both polar and equatorial regions of the Earth's satellite.
Detailed analysis of the data sent by the LLRI helps in
understanding the internal structure of the Moon as well as
the way that celestial body evolved.
It may be recalled that earlier, three payloads of
Chandrayaan-1 -- Terrain Mapping Camera (TMC), Radiation Dose
Monitor (RADOM) and Moon Impact Probe (MIP) -- were
successfully turned on.
The MIP, carrying the Indian tricolour, was released
from the spacecraft on November 14 and 25 minutes later,
successfully impacted the lunar surface as intended. TMC took
pictures of the Earth and Moon when the spacecraft was on its
way to Moon.
The statement said that TMC has been taking breathtaking
pictures of the lunar panorama. The RADOM was also switched on
in the earth orbit itself, it added.
The pictures and other scientific data sent by
Chandrayaan-1 from the lunar orbit have been received by
antennas of Indian Deep Space Network (IDSN) at Byalalu on the
outskirts of the city.
The spacecraft operations are being carried out from the
Satellite Control Centre (SCC) of ISRO Telemetry, Tracking and
Command Network (ISTRAC) at Bangalore.
Bureau Report
First Published: Sunday, November 16, 2008, 00:00