Chandrayaan-1 is an unmanned lunar exploration mission by the Indian Space Research Organisation (ISRO), India's national space agency. The mission includes a lunar orbiter and an impactor. The spacecraft was launched by a modified version of the Polar Satellite Launch Vehicle on 22 October 2008 from Satish Dhawan Space Centre, Sriharikota, Andhra Pradesh. 'Chandrayaan' (in many Indian languages) roughly translates to 'Moon-vehicle'.The remote sensing satellite weighs 1,308 kilograms (2,884 lb) (590 kilograms (1,301 lb) initial orbit mass and 504 kilograms (1,111 lb) dry mass) and carries high resolution remote sensing equipment for visible, near infrared, soft and hard X-ray frequencies. Over a two-year period, it is intended to survey the lunar surface to produce a complete map of its chemical characteristics and 3-dimensional topography. The polar regions are of special interest, as they might contain water ice.
The spacecraft was successfully launched on 22 October 2008 at 6:22 am Indian Standard Time (00:52 UTC). After the spacecraft reaches its lunar transfer orbit, it will take 5.5 days to reach the Moon. The estimate cost for the project is Rs. 3.86 billion (US$ 80 million). Two scientists considered largely responsible for the success of the project are Mylswamy Annadurai of Tamil Nadu, the project in charge, and S. K. Shivakumar of Mysore, considered the "father" of India's deep space network.
The mission includes five ISRO payloads and six payloads from other international space agencies including NASA, ESA, and the Bulgarian Aerospace Agency, which are being carried free of cost.
Mission ObjectivesTo launch and orbit a spacecraft in lunar polar orbit and conduct scientific studies.
To carry out high resolution mapping of topographic features in 3D, distribution of various minerals and elemental chemical species including radioactive nuclides covering the entire lunar surface using a set of remote sensing payloads. The new set of data would help in unraveling mysteries about the origin and evolution of the Solar System in general and that of the Moon in particular, including its composition and mineralogy.
Realize the mission goal of harnessing the science payloads, lunar craft and the launch vehicle with suitable ground support system including DSN station, integration and testing, launching and achieving lunar orbit of ~100 km, in-orbit operation of experiments, communication/telecommand, telemetry data reception, quick look data and archival for scientific utilization by identified group of scientists.
SpecificationsMass
1380 kg at launch, 675 kg at lunar orbit, and 523 kg after releasing the impactor.
Dimensions
Cuboid in shape of approximately 1.5 m
Communications
X band, 0.7 m diameter parabolic antenna for payload data transmission. The Telemetry, Tracking & Command (TTC) communication operates in S band frequency.
Power
The spacecraft is mainly powered by its solar array, which includes one solar panel covering a total area of 2.15 x 1.8 m2 generating 700 W of power, which is stored in a 36 A·h Lithium-ion battery. The spacecraft uses a bipropellant integrated propulsion system to reach lunar orbit as well as orbit and altitude maintenance while orbiting the Moon.
Specific areas of studyHigh-resolution mineralogical and chemical imaging of permanently shadowed north and south polar regions.
Search for surface or sub-surface water-ice on the Moon, specially at lunar poles.
Identification of chemical end members of lunar high land rocks.
Chemical stratigraphy of lunar crust by remote sensing of central upland of large lunar craters, South Pole Aitken Region (SPAR) etc., where interior material may be expected.
To map the height variation of the lunar surface features along the satellite track.
Observation of X-ray spectrum greater than 10 keV and stereographic coverage of most of the Moon's surface with 5m resolution
To provide new insights in understanding the Moon's origin and evolution.
The scientific payload has a total mass of 90 kg and contains six Indian instruments and six foreign instruments.
The Terrain Mapping Camera (TMC) is a CCD camera with 5 m resolution and a 40 km swath in the panchromatic band and will be used to produce a high-resolution map of the Moon.The Hyper Spectral Imager (HySI) will perform mineralogical mapping in the 400-900 nm band with a spectral resolution of 15 nm and a spatial resolution of 80 m.
The Lunar Laser Ranging Instrument (LLRI) will determine the surface topography.
An X-ray fluorescence spectrometer (C1XS) covering 1- 10 keV with a ground resolution of 25 km and a Solar X-ray Monitor (XSM) to detect solar flux in the 1–10 keV range. C1XS will be used to map the abundance of Mg, Al, Si, Ca, Ti, and Fe at the surface, and will monitor the solar flux. This payload is a collaboration between Rutherford Appleton laboratory, U.K, ESA and ISRO.
A High Energy X-ray/gamma ray spectrometer (HEX) for 30- 200 keV measurements with ground resolution of 40 km, the HEX will measure U, Th, 210Pb, 222Rn degassing, and other radioactive elements
Moon Impact probe (MIP) developed by the ISRO, is a small satellite that will be carried by Chandrayaan-1 and will be ejected once it reaches 100 km orbit around Moon, to impact on the Moon. MIP carries three more instruments, namely, a high resolution mass spectrometer, an S-Band altimeter and a video camera. The MIP also carries with it a picture of the Indian flag, its presence marking as only the fourth nation to place a flag on the Moon after Russia (however, Luna 2 carried the Soviet flag and coat of arms), United States and Japan.Among foreign payloads, The Sub-keV Atom Reflecting Analyser (SARA) from the ESA will map composition using low energy neutral atoms sputtered from the surface.
The Moon Mineralogy Mapper (M3) from Brown University and JPL (funded by NASA) is an imaging spectrometer designed to map the surface mineral composition.
A near infrared spectrometer (SIR-2) from ESA, built at the Max Planck Institute for Solar System Research, Polish Academy of Science and University of Bergen, will also map the mineral composition using an infrared grating spectrometer. The instrument will be similar to that of the Smart-1 SIR.
S-band miniSAR, designed, built and tested for NASA by a large team that includes the Naval Air Warfare Center, Johns Hopkins University Applied Physics Laboratory, Sandia National Laboratories, Raytheon and Northrop Grumman; it is the active SAR system to search for lunar polar ice. The instrument will transmit right polarized radiation with a frequency of 2.5 GHz and will monitor the scattered left and right polarised radiation. The Fresnel reflectivity and the circular polarisation ratio (CPR) are the key parameters deduced from these measurements. Ice shows the Coherent Backscatter Opposition Effect which results in an enhancement of reflections and CPR, so that water content of the Moon polar region can be estimated.
Radiation Dose Monitor (RADOM-7) from Bulgaria is to map the radiation environment around the Moon.
Space flightThe launch took place on 22 October 2008 at 6.22 am IST from Satish Dhawan Space Centre using ISRO's PSLV launch rocket. The 44.4 metre tall four-stage rocket was used to launch the spacecraft into orbit. Chandrayaan will take 15 days to reach the lunar orbit. ISRO's telemetry, tracking and command network (ISTRAC) at Peenya in Bangalore, will be tracking and controlling Chandrayaan-1 over the next two years of its life span.
Since its perfect launch, Chandrayaan has performed several engine burns, moving it into the designated Geostationary transfer orbit (GTO) around earth and has successfully communicated with base center.
Once in GTO, Chandrayaan's on-board motor will be fired to take it to the lunar orbit with 1,019 km perigee and 386,194 km apogee from the Earth around November 8. This orbit will take the spacecraft to the vicinity of the moon.
The spacecraft will rotate for about five-and-a-half days before firing the engine to slow its velocity for moon's gravity to capture it. As the spacecraft approaches the moon, its speed will be reduced to enable the gravity of the moon to capture it into an elliptical orbit. A series of engine burns will then lower its orbit to its intended 100 km circular polar orbit. Following this, the Moon Impact Probe (MIP) will be ejected from Chandrayaan-1 and all the scientific instruments/payloads are commissioned.

1 comment:
very informative. why does everyone go on and on about the cost? Is it a great achievement to underpay your scientists?
Post a Comment