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COMSTAT, and other GIS crime mapping applications have since become widespread and almost commonplace in law enforcement agencies nationwide as well as worldwide. Probably one of the most invaluable tools available for effective crime fighting is information. Using maps to display that information is an old tool. The advent of desktop computers has significantly increased the role of computer mapping. The availability of low-cost and user-friendly GIS applications has further served to increase the use of GIS in crime mapping. The 1994 Violent Crime Control and Law Enforcement Act provided a boost to the implementation of GIS by providing funding for crime prevention programs. The added functionality of a GIS over computer mapping has increased the capabilities of crime fighting. GIS’ replacement of paper-based or flat file searching increases the efficiency and speed of the analysis. GIS helps crime analysis in many ways. The foremost use is to visualize crime occurrences. This allows law enforcement agencies to understand where crime is occurring as well as determine if there are any patterns. Areas of high crime density are known as hot spots. Hot spot analysis is a valuable tool as it allows police to not only identify areas of high crime but also explore variables that are affecting crime patterns. For example, mapping drug arrests may show an increased density around locations that have public telephones. With this information, law enforcement agencies can be more efficient in their crime fighting tactics from increasing patrols around such locations or by proactive measures by removing problematic public phones that persistently attract drug transactions. As the use of GIS evolves in crime analysis, new and innovative applications are emerging. One of the latest examples of such creativeness is the use of GIS to triangulate gunfire. In conjunction with consultants, the Police Department in Redwood City, California implemented ShotSpotter. This application uses strategically placed microphones in conjunction with GIS to locate gunshots using triangulation. The application, created with ESRI’s MapObjects, can then search the property information to determine the address of the nearest residence or business to the gunfire. The inventiveness of this program earned it an induction by the Smithsonian Institute into its 2000 Information Technology Innovation Collection. Crime Mapping on the Web With the increase of GIS in crime mapping has come increased public access to crime data. The most accessible and popular method emerging is through Internet access. In 1995, the Police Department of Vacaville, California was one of the first law enforcement agencies to put crime maps on the web. Now, there are many agencies that publish their crime data via the Internet. Not everyone is happy about the proliferation of crime data on the Internet. Real estate developers and agents feel that public crime data in high crime data will lower housing prices. As with most debates about web publishing of GIS data, right-to-privacy advocates worry about backlashes towards former felons especially convicted sex offenders and domestic violence criminals. The reality of the situation is that most of this information is public information (check the crime blotter section of your local newspaper) although the ease of crime mapping makes this information more readily available.
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Global Navigation Satellite System (GNSS) is the standard generic term for satellite navigation systems that provide autonomous geo-spatial positioning with global coverage. A GNSS allows small electronic receivers to determine their location (longitude, latitude, and altitude) to within a few metres using time signals transmitted along a line of sight by radio from satellites. Receivers on the ground with a fixed position can also be used to calculate the precise time as a reference for scientific experiments. As of 2007, the United States NAVSTAR Global Positioning System (GPS) is the only fully operational GNSS. The RussianGLONASS is a GNSS in the process of being restored to full operation. The European Union'sGalileo positioning system is a GNSS in initial deployment phase, scheduled to be operational in 2013. China has indicated it may expand its regional Beidou navigation system into a global system. India'sIRNSS, a regional system is intended to be completed and operational by 2012. 1. GNSS classification GNSS that provide enhanced accuracy and integrity monitoring usable for civil navigation are classified as follows: GNSS-1 is the first generation system and is the combination of existing satellite navigation systems (GPS and GLONASS), with Satellite Based Augmentation Systems (SBAS) or Ground Based Augmentation Systems (GBAS). In the United States, the satellite based component is the Wide Area Augmentation System (WAAS), in Europe it is the European Geostationary Navigation Overlay Service (EGNOS), and in Japan it is the Multi-Functional Satellite Augmentation System (MSAS). Ground based augmentation is provided by systems like the Local Area Augmentation System (LAAS). GNSS-2 is the second generation of systems that independently provides a full civilian satellite navigation system, exemplified by the European Galileo positioning system. These systems will provide the accuracy and integrity monitoring necessary for civil navigation. This system consists of L1 and L2 frequencies for civil use and L5 for system integrity. Development is also in progress to provide GPS with civil use L2 and L5 frequencies, making it a GNSS-2 system. Core Satellite navigation systems, currently GPS, Galileo and GLONASS. Global Satellite Based Augmentation Systems (SBAS) such as Omnistar and StarFire. Regional SBAS including WAAS(US), EGNOS (EU), MSAS (Japan) and GAGAN (India). Regional Satellite Navigation Systems such a QZSS (Japan), IRNSS (India) and Beidou (China). Continental scale Ground Based Augmentation Systems (GBAS) for example the Australian GRAS and the US Department of Transportation National Differential GPS (DGPS) service. Regional scale GBAS such as CORS networks. Local GBAS typified by a single GPS reference station operating Real Time Kinematic (RTK) corrections. 2. History and theory Early predecessors were the ground based DECCA, LORAN and Omega systems, which used terrestrial longwaveradio transmitters instead of satellites. These positioning systems broadcast a radio pulse from a known "master" location, followed by repeated pulses from a number of "slave" stations. The delay between the reception and sending of the signal at the slaves was carefully controlled, allowing the receivers to compare the delay between reception and the delay between sending. From this the distance to each of the slaves could be determined, providing a fix. The first satellite navigation system was Transit, a system deployed by the US military in the 1960s. Transit's operation was based on the Doppler effect: the satellites traveled on well-known paths and broadcast their signals on a well known frequency. The received frequency will differ slightly from the broadcast frequency because of the movement of the satellite with respect to the receiver. By monitoring this frequency shift over a short time interval, the receiver can determine its location to one side or the other of the satellite, and several such measurements combined with a precise knowledge of the satellite's orbit can fix a particular position. Part of an orbiting satellite's broadcast included its precise orbital data. In order to ensure accuracy, the US Naval Observatory (USNO) continuously observed precisely the orbits of these satellites. As a satellite's orbit deviated, the USNO would send the updated information to the satellite. Subsequent broadcasts from an updated satellite would contain the most recent accurate information about its orbit. Modern systems are more direct. The satellite broadcasts a signal that contains the position of the satellite and the precise time the signal was transmitted. The position of the satellite is transmitted in a data message that is superimposed on a code that serves as a timing reference. The satellite uses an atomic clock to maintain synchronization of all the satellites in the constellation. The receiver compares the time of broadcast encoded in the transmission with the time of reception measured by an internal clock, thereby measuring the time-of-flight to the satellite. Several such measurements can be made at the same time to different satellites, allowing a continual fix to be generated in real time. Each distance measurement, regardless of the system being used, places the receiver on a spherical shell at the measured distance from the broadcaster. By taking several such measurements and then looking for a point where they meet, a fix is generated. However, in the case of fast-moving receivers, the position of the signal moves as signals are received from several satellites. In addition, the radio signals slow slightly as they pass through the ionosphere, and this slowing varies with the receiver's angle to the satellite, because that changes the distance through the ionosphere. The basic computation thus attempts to find the shortest directed line tangent to four oblate spherical shells centered on four satellites. Satellite navigation receivers reduce errors by using combinations of signals from multiple satellites and multiple correlators, and then using techniques such as Kalman filtering to combine the noisy, partial, and constantly changing data into a single estimate for position, time, and velocity. 3. Civil and military uses The original motivation for satellite navigation was for military applications. Satellite navigation allows for hitherto impossible precision in the delivery of weapons to targets, greatly increasing their lethality whilst reducing inadvertent casualties from mis-directed weapons. (See smart bomb). Satellite navigation also allows forces to be directed and to locate themselves more easily, reducing the fog of war. In these ways, satellite navigation can be regarded as a force multiplier. In particular, the ability to reduce unintended casualties has particular advantages for wars where public relations is an important aspect of warfare. For these reasons, a satellite navigation system is an essential asset for any aspiring military power. GNSS systems have a wide variety of uses: Navigation, ranging from personal hand-held devices for trekking, to devices fitted to cars, trucks, ships and aircraft Time transfer and synchronization Location-based services such as enhanced 911 Surveying Entering data into a geographic information system Search and rescue Geophysical Sciences Tracking devices used in wildlife management Asset Tracking, as in trucking fleet management Road Pricing Location-based media Note that the ability to supply satellite navigation signals is also the ability to deny their availability. The operator of a satellite navigation system potentially has the ability to degrade or eliminate satellite navigation services over any territory it desires. 4. Current global navigation systems 4.1 GPS The United States' Global Positioning System (GPS), which as of 2007 is the only fully functional, fully available global navigation satellite system. It consists of up to 32 medium Earth orbit satellites in six different orbital planes, with the exact number of satellites varying as older satellites are retired and replaced. Operational since 1978 and globally available since 1994, GPS is currently the world's most utilized satellite navigation system. 4.2 GLONASS The formerly Soviet, and now Russian, Global'naya Navigatsionnaya Sputnikovaya Sistema, or GLONASS, was a fully functional navigation constellation but since the collapse of the Soviet Union has fallen into disrepair, leading to gaps in coverage and only partial availability. The Russian Federation has pledged to restore it to full global availability by 2010 with the help of India, who is participating in the restoration project. 5. Proposed Global Navigation Systems 5.1 IRNSS The Indian Regional Navigational Satellite System (IRNSS) is an autonomous regional satellite navigation system being developed by Indian Space Research Organisation which would be under the total control of Indian government. The government approved the project in May 2006, with the intention of the system to be completed and implemented by 2012. It will consist of a constellation of 7 navigational satellites by 2012. All the 7 satellites will placed in the Geostationary orbit (GEO) to have a larger signal footprint and lower number of satellites to map the region. It is intended to provide an absolute position accuracy of better than 20 meters throughout India and within a region extending approximately 2,000 km around it. A goal of complete Indian control has been stated, with the space segment, ground segment and user receivers all being built in India. 5.2 Compass China has indicated they intend to expand their regional navigation system, called Beidou or Big Dipper, into a global navigation system; a program that has been called Compass in China's official news agency Xinhua. The Compass system is proposed to utilize 30 medium Earth orbit satellites and five geostationary satellites. Having announced they are willing to cooperate with other countries in Compass's creation, it is unclear how this proposed program impacts China's commitment to the international Galileo position system. 5.3 DORIS Doppler Orbitography and Radio-positioning Integrated by Satellite (DORIS) is a French precision navigation system. 5.4 Galileo The European Union and European Space Agency agreed on March 2002 to introduce their own alternative to GPS, called the Galileo positioning system. At a cost of about GBP £2.4 billion, the system is scheduled to be working from 2012. The first experimental satellite was launched on 28 December2005. Galileo is expected to be compatible with the modernized GPS system. The receivers will be able to combine the signals from both Galileo and GPS satellites to greatly increase the accuracy. 5.5 QZSS The Quasi-Zenith Satellite System (QZSS), is a proposed three-satellite regional time transfer system and enhancement for GPS covering Japan. The first satellite is scheduled to be launched in 2008. 6. GNSS Augmentation GNSS Augmentation involves using external information, often integrated into the calculation process, to improve the accuracy, availability, or reliability of the satellite navigation signal. There are many such systems in place and they are generally named or described based on how the GNSS sensor receives the information. Some systems transmit additional information about sources of error (such as clock drift, ephemeris, or ionospheric delay), others provide direct measurements of how much the signal was off in the past, while a third group provide additional navigational or vehicle information to be integrated in the calculation process. Examples of augmentation systems include the Wide Area Augmentation System, the European Geostationary Navigation Overlay Service, the Multi-functional Satellite Augmentation System, Differential GPS, and Inertial Navigation Systems. 7. Low Earth orbit satellite phone networks The two current operational low Earth orbit satellite phone networks are able to track transceiver units with accuracy of a few kilometers using Doppler shift calculations from the satellite. The coordinates are sent back to the transceiver unit where they can be read using AT commands or a graphical user interface. This can also be used by the gateway to enforce restrictions on geographically bound calling plans.
The Landsat program is the longest running enterprise for acquisition of imagery of Earth from space. The first Landsat satellite was launched in 1972; the most recent, Landsat 7, was launched on April 15, 1999. The instruments on the Landsat satellites have acquired millions of images. The images, archived in the United States and at Landsat receiving stations around the world, are a unique resource for global change research and applications in agriculture, cartography, geology, forestry, regional planning, surveillance, education and national security. Landsat 7 data has eight spectral bands with spatial resolutions ranging from 15 to 60 meters. 1. History Hughes Santa Barbara Research Center initiated design and fabrication of the first three MSS Multi-Spectral-Scanners in the same year man landed on the moon, 1969. The first prototype MSS was completed within nine months by fall of 1970 when it was tested by scanning Half Dome at Yosemite National Park. The initial centerline for the primary layout of the MSS was drawn by Jim Kodak, the opto-mechanical design engineer who designed the Pioneer spacecraft optical camera, the first instrument to leave the solar system. The program was called the Earth Resources Observation Satellites Program when it was initiated in 1966, but the name was changed to Landsat in 1975. In 1979, Presidential Directive 54 under President of the United StatesJimmy Carter transferred Landsat operations from NASA to NOAA, recommended development of long term operational system with four additional satellites beyond Landsat 3, and recommended transition to private sector operation of Landsat. This occurred in 1985 when the Earth Observation Satellite Company (EOSAT), a partnership of Hughes Aircraft and RCA, was selected by NOAA to operate the Landsat system under a ten year contract. EOSAT operated Landsats 4 and 5, had exclusive rights to market Landsat data, and was to build Landsats 6 and 7. In 1989, this transition had not been fully completed when NOAA's funding for the Landsat program ran out and NOAA directed that Landsats 4 and 5 be shut down, but an act of the United States Congress provided emergency funding for the rest of the year. Funding ran out again in 1990 and once again Congress provided emergency funding to NOAA for six more months of operations, requesting that agencies that used Landsat data provide the funding for the other six months of the upcoming year. The same funding problem and solution was repeated in 1991. In 1992, various efforts were made to finally procure funding for follow on Landsats and continued operations, but by the end of the year EOSAT ceased processing Landsat data. Landsat 6 was finally launched on October 5, 1993, but was lost in a launch failure. Processing of Landsat 4 and 5 data was resumed by EOSAT in 1994. NASA finally launched Landsat 7 on April 15, 1999. The value of the Landsat program was recognized by Congress in October 1992 when it passed the Land Remote Sensing Policy Act (Public Law 102-555) authorizing the procurement of Landsat 7 and assuring the continued availability of Landsat digital data and images, at the lowest possible cost, to traditional and new users of the data. 2. Satellite chronology Landsat 1 (originally named Earth Resources Technology Satellite 1) - launched July 23, 1972, terminated operations in 1978 Landsat 2 - launched January 22, 1975, terminated in 1981 Landsat 3 - launched March 5, 1978, terminated 1983 Landsat 4 - launched July 16, 1982, terminated 1993 Landsat 5 - launched March 1, 1984, still functioning. Landsat 6 - launched October 5, 1993, failed to reach orbit Landsat 7 - launched April 15, 1999, still functioning, but with faulty scan line corrector (May 2003) 3. Technical details The Multi-Spectral-Scanner had a 9" fused silica dinner-plate mirror epoxy bonded to three invar tangent bars mounted to base of a Ni/ Aubrazed Invar frame in a serreuire truss that was arranged with four "Hobbs-Links" (conceived by Dr. Gregg Hobbs) crossing at mid truss. This construct ensured the secondary mirror would simply oscillate about the primary optic axis to maintain focus despite vibration inherent from the 14-inch (360 mm) Be scan mirror. This engineering solution allowed the US to develop LANDSAT at least five years ahead of French SPOT which first used CCD arrays to stare without need for a scanner. The MSS FPA, or Focal Plane Array consisted of 24 square optical fibers extruded down to .0002"square fiber tips in a 4x6 array to be scanned across the Nimbus spacecraft path in a +/-6 degree scan as the satellite was in a 10:30 polar orbit, hence it had to be launched from Vandenburg AFB. The fiber optic bundle was embedded in a fiber optic plate to be terminated at a relay optic device that transmitted fiber end signal on into six photodiodes and 18 photomultiplier tubes that were arrayed across a 0.30-inch (7.6 mm) thick aluminum tool plate, with sensor weight balanced vs the 9-inch (230 mm) telescope on opposite side. This main plate was assembled on a frame, then attached to the silver-loaded magnesium housing with helicoil fasteners. Key to MSS success was the scan monitor mounted on the underbelly of the Mg housing. It consisted of a diode source & sensor mounted at ends of four flat mirrors that were tilted so that it took 14 bounces for a beam to reflect length of the three mirrors from source to sender striking Be scan mirror seven times as it reflected seven times off the flat mirrors. It only sensed three positions, both ends of scan & the mid scan, but that was all that was required to determine where MSS was pointed and electronics scanning could be calibrated to display a map.
The remote sensing satellite weighs 1,380 kilograms (3,042 lb) at launch and 675 kilograms (1,488 lb) at lunar orbit 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 ice.
The spacecraft was successfully launched on 22 October 2008 at 06:23 IST (00:52 UTC). The estimated cost for the project is Rs. 3.86 billion (US$ 80 million).
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.
1. Objectives
The stated scientific objectives of the mission are:
To design, develop and launch and orbit a spacecraft around the Moon using Indian made launch vehicle.
Conduct scientific experiments using instruments on-board the spacecraft which will yield the following results:
To prepare a three-dimensional atlas (with high spatial and altitude resolution of 5-10 m) of both near and far side of the moon.
To conduct chemical and mineralogical mapping of the entire lunar surface for distribution of mineral and chemical elements such as Magnesium, Aluminum, Silicon, Calcium, Iron and Titanium as well as high atomic number elements such as Radon, Uranium & Thorium with high spatial resolution.
To impact a sub-satellite ( Moon Impact Probe -MIP ) on the surface on the Moon as a fore-runner to future soft landing missions.
2. Specifications
After full integration, the Chandrayaan-1 spacecraft (left) is seen being loaded into the Thermovac Chamber (right)
Mass
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 m generating 700 W of power, which is stored in a 36 A·hLithium-ion battery.[12] The spacecraft uses a bipropellant integrated propulsion system to reach lunar orbit as well as orbit and altitude maintenance while orbiting the Moon.[11]
3. Specific areas of study
High-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.
4. Payloads
Chandrayaan 1
The scientific payload has a total mass of 90 kg and contains six Indian instruments and six foreign instruments.
4.1 Indian
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 aim of this instrument is to completely map the topography of the moon. The camera works in the visible region of the electromagnetic spectrum and captures black and white stereo images. When used in conjunction with data from Lunar Laser Ranging Instrument (LLRI), it can help in better understanding of the lunar gravitational field as well. TMC is built by ISRO's Space Applications Centre (SAC) of Ahmedabad TMC was successfully tested on 29 October2008 through a set of commands issued from ISTRAC.
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.[16] 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
The 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 the Soviet Union, United States and Japan.
4.2 Non-Indian
SARA, The Sub-keV Atom Reflecting Analyser from the ESA will map composition using low energy neutral atoms sputtered from the surface.
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 polarised 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.
PSLV-C11(in the picture) was used to launch Chandrayaan-1.
Chandrayaan-1 was launched on 22 October2008 at 6.22 am IST from Satish Dhawan Space Centre using ISRO's 44.4 metre tall four-stage PSLV launch rocket. 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 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. This GTO was characterized by a 22,860 km apogee by 255 km perigee and was the initial orbit from which the five orbit raising maneuvers will be performed.
Once in GTO, Chandrayaan's on-board motor will be fired to increase its orbit around the earth. The orbit will be raised five times till it reaches 1,019 km perigee and 386,194 km apogee from the Earth on 8 November. 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.
Chandrayaan-1 completed four orbits around the Earth, on 23 October: "The health of the spacecraft is normal and (it is) doing fine. Spinning in elliptical orbit once in every 6 hours and 30 minutes, it has completed four orbits and is in the fifth orbit."
The first orbit raising manoeuvre of Chandrayaan-1 spacecraft was performed at 09:00 hrs IST on 23 October 2008 when the spacecraft’s 440 Newton Liquid Engine was fired for about 18 minutes by commanding the spacecraft from Spacecraft Control Centre (SCC) at ISRO Telemetry, Tracking and Command Network (ISTRAC) at Peenya, Bangalore. With this engine firing, Chandrayaan-1’s apogee has been raised to 37,900 km, while its perigee has been raised a little, to 305 km. In this orbit, Chandrayaan-1 spacecraft takes about 11 hours to go round the Earth once.
The second orbit raising manoeuvre of Chandrayaan-1 spacecraft was carried out on 25 October 2008 at 05:48 IST when the spacecraft’s 440 Newton Liquid Engine was fired for about 16 minutes by commanding the spacecraft from Spacecraft Control Centre (SCC) at ISRO Telemetry, Tracking and Command Network (ISTRAC) at Peenya, Bangalore. With this engine firing, Chandrayaan-1’s apogee has been further raised to 74,715 km, while its perigee has been raised to 336 km, thus completing 20 percent of its journey. In this orbit, Chandrayaan-1 spacecraft takes about twenty-five and a half hours to go round the Earth once. This is the first time an Indian spacecraft has gone beyond the 36,000 km high geostationary orbit and reached an altitude more than twice that height.
The third orbit raising manoeuvre was initiated on 26 October 2008 at 07:08 IST. The Liquid Apogee Motor was fired for about nine and a half minutes. With this, Chandrayaan-1 entered a much higher elliptical orbit around the Earth. The apogee of this orbit lies at 164,600 km, instead of 199,277 km apogee as originally announced by the Indian Space Research Organisation (ISRO), while the perigee is at 348 km. In this orbit, Chandrayaan-1 takes about 73 hours to go round the Earth once.
The fourth orbit raising manoeuvre was carried out on October 29, 2008 at 07:38 IST. The spacecraft's liquid engine was fired for about three minutes, raising it to a more elliptical orbit whose apogee lies at 267,000 km while the perigee lies at 465 km. This makes its present orbit extends more than half the way to moon. In this orbit, the spacecraft takes about six days to go round the Earth once.
The Terrain Mapping camera (TMC) on board Chandrayaan-1 spacecraft was successfully operated on October 29, 2008 through a series of commands issued from the Spacecraft Control Centre of ISRO Telemetry, Tracking and Command Network (ISTRAC) at Bangalore.
The first image taken at 8:00 am IST from a height of 9,000 km shows the Northern coast of Australia.
The second image taken at 12:30 pm from a height of 70,000 km shows Australia’s Southern Coast.
The fifth and final orbit raising manoeuvre was carried out on November 4, 2008 04:56 am IST. The spacecraft’s liquid engine was fired for about two and a half minutes resulting in Chandrayaan-1 entering the Lunar Transfer Trajectory with an apogee of about 380,000 km.
It is projected that Chandrayaan-1 will approach the Moon on November 8, 2008. Its liquid engine will then be fired again to insert the spacecraft into lunar orbit.
6. Team
The scientists considered instrumental to the success of the Chandrayaan-1 project are
S. K. Shivkumar – Director - Telemetry, Tracking and Command Network.
George Koshi –Mission Director
Srinivasa Hegde – Mission Director
M Y S Prasad – Associate Director of the Sriharikota Complex and Range Operations Director
J N Goswami – Director of the Ahmedabad-based Physical Research Laboratory and Principal Scientific Investigator of Chandrayaan-1
Narendra Bhandari – Head, ISRO`s Planetary Sciences and Exploration program
7. Chandrayaan II
The ISRO is also planning a second version of Chandrayaan named Chandrayaan II. According to ISRO Chairman G. Madhavan Nair, "The Indian Space Research Organisation (ISRO) hopes to land a motorised rover on the Moon in 2009 or 2010, as a part of its second Chandrayaan mission. The rover will be designed to move on wheels on the lunar surface, pick up samples of soil or rocks, do in site chemical analysis and send the data to the mother-spacecraft Chandrayaan II, which will be orbiting above. Chandrayaan II will transmit the data to Earth."
