INDIAS FIRST MISSION TO MOON
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CHANDRAYAAN - 1
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Expanding the scientific knowledge about the moon, upgrading India’s technological capability and providing challenging opportunities for planetary research for the younger generation
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Scientific Objective:

High resolution remote sensing of the moon in the visible, near infrared, low energy X-ray and high-energy X-ray regions for: 

• Preparing 3-dimensional atlas of regions of scientific interest with a high spatial and altitude resolution of 5-10 m

• Chemical mapping of the entire lunar surface for elements such as Mg, Al, Si, Ca, Fe and Ti with a spatial resolution of 10 km and elements of high atomic numbers (Z), such as 222Rn, U, Th and Gd with a spatial resolution of 20 km
click to enlarge
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Scientific Instruments:

• Terrain Mapping Camera (TMC) with stereo imaging capability operating in panchromatic band, with 5 m spatial resolution and 40 km swath

• A Hyper-Spectral Imager (HySI) operating in 400-900 nm band with a spectral resolution of 15 nm, spatial resolution of 80 m and a swath of 40 km

• A Lunar Laser Ranging Instrument (LLRI) with a height resolution of 10 m

• A Low Energy (1-10 keV) X-ray spectrometer (LEX) for measuring fluorescent X-rays emanating from lunar surface with a footprint of 10 km

• A High Energy X-ray (10-200 keV) mapping camera (HEX) with a footprint of 20 km to identify degassing faults or zones on the moon by mapping 222Rn and its radioactive daughter210Pb

• Payloads weighing up to about 10 kg of other space agencies could be included



  


Spacecraft:

Physical : 1.5 m cuboid-shaped main body with a dry weight of 525 kg in lunar orbit

Control : 3-axis stabilized using reaction wheels and attitude control thrusters, star sensors, inertial reference unit and accelerometers for attitude determination

Power : Single sided canted solar array to generate 750 W. Li-Ion batteries for eclipse operations

Propulsion : Bipropellant system for transferring from GTO to lunar orbit and for orbit and attitude maintenance

Communication : TTC in S-band and scientific payload data transmission in X-band
Mission Life : 2 years
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New Technologies:

• Lithium-ion batteries
• Gimballed antenna system
• Miniaturized communication system
• Miniaturized star sensor
• spacecraft bus management
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New Facilities:

• Deep Space Network located in Bangalore with 180 deg longitudinal shift with respect to Goldstone, California, USA. Supports spacecraft at a slant range of upto 4,00,000 km for TTC and payload data reception, 34 m diameter antenna with an uplink power of 2 kW. Receives spacecraft data transmission in X-band with a transmitted power of 2 W

• National Science Data Centre to process raw data into user-friendly format to be set up at a suitable location
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Polar Satellite Launch Vehicle (PSLV)

• Lift off weight : 295 tonne

• Height : 44.4 m

• Payload Capability : 525 kg in 100 km lunar orbit 1050 kg into Geosynchronous Transfer Orbit (200 km x 36000 km)
100 kg to 1350 kg payloads to Sun Synchronous Orbit

• Proven successive successes

• Demonstrated multiple satellite launch capability


  Mission Sequence:

• Launch into 240 km X 36000 km GTO by PSLV

• Two consecutive in-plane perigee maneuvers to achieve 3,86,000 km apogee (Lunar Transfer Trajectory -LTT)

• Coasting for 5 ½ days in LTT prior to lunar encounter

• Lunar capture at peri-selene (nearest point in lunar orbit)

• Satellite in near circular 1,000 km orbit of the moon

• Solar panel deployment

• In-plane corrections to reduce orbit height to 200 km, polar

• Study of orbit perturbations for 1-2 weeks

• Reduce orbit altitude to 100 km circular, polar
 
Click to see enlarged image