CHANDRAYAAN REACHED 100 KM FORM LUNAR SURFACE

Matt_dk writes "Today, Chandrayaan-1 spacecraft has successfully reached its intended operational orbit at a height of about 100 km from the lunar surface. This followed a series of three orbit reduction manoeuvres conducted during the past three days by repeatedly firing the spacecraft's 440 Newton Liquid Engine. The next major event of Chandrayaan-1 mission planned in the coming days is the release of Moon Impact Probe (MIP) from the spacecraft and its eventual hitting of the moon's surface."

INDIAN FLAG ON MOON

NEW DELHI: Two days before the launch of India's first lunar orbiter, chairman of the Indian Space Research Organisation (ISRO) G. Madhavan Nair said on Monday that India will plant its flag on the moon to help establish its presence on the earth's only natural satellite.

India will drop its flag on the moon to establish its presence, Nair said in an interview. This will make India the fourth country after the US, Russia, and Japan to have its flag on the moon.

Asked for the geopolitical reason behind the planting of the flag, Nair said: "Today, as per the international charter, the moon belongs to the global community. Nobody can make special claim on the surface. But in due course, we don't know how things will change. But our presence will be established through this mission."

Nair also reiterated in the interview that ISRO planned to put a man in space by 2015. "If certain finer observation are to be made, online decisions have to be made, the presence of man becomes important," he said.

"The man behind the instrument. And also the reaction time for any decision will be a fraction of a second, whereas you know it takes almost eight seconds for the data to come from the moon to the earth and then again sent back and so on, and here also somebody has to analyse....so ultimately if you want to do a perfect experiment, man behind the instrument is a must."

Nair said it would cost around Rs.100 billion to put a man in space. However, he added, "in the Indian context we are committed to taking the space technology for grass root applications. We have done that and we will continue to do so. So nearly 80 percent of the budget is going to be spent on programmes which are relevant to the common man."

The lunar orbiter mission Chandrayaan that will be launched Wednesday will look for water on the moon, Nair confirmed. "If you are thinking of establishing lunar colony, water is essential element for that and if from it you can generate oxygen, and also if you can decompose and generate into fuel which is required for interplanetary travel, so the presence of water is a very-very important element for further exploration."

Nair also confirmed that the mission would look for Helium-3, one of the fuels for nuclear fusion. "Even one tonne of that can sustain the entire country's energy for one year," he pointed out. Reiterating that there was Helium-3 on the moon, he added: "Is it in abundant quantity, whether we can exploit, these are question marks."

The ISRO chief said that after the moon, the organisation had its sights set on Mars. "The GSLV can take a nearly 500 kg spacecraft to Mars. So if there are good ideas about experimental exploration of that system we can have the Mars mission and in about 3-4 years."

"If we want to maintain our leadership naturally we have to have the scientific goals which is set ahead so that we can be really either at par or ahead of the others in some of the fields. So this is a really challenging task. We believe that India, such a big nation, huge resources, both natural and human resource... we should be in leadership position as far as our space technology is concerned."

Asked if the space programme was cost effective, Nair said that for every rupee spent, ISRO gave back Rs.1.50 to the Indian society. "That is the first part of it. The second part is, the human resource and the technology we create, that is not valued. That is tremendous."

Asked if India have a colony on the moon sometime, Nair said: "We cannot lag behind others in this race. We have to really catch up and we should have our own technology for the manned capsule.

"Of course initial thing would be around earth itself, then from there how to send a man to the moon etc has to be considered. And today with the economic growth what you are seeing in the country this is affordable.

"And a very small fraction of the national budget we spend on space technology. It is really worth it. In fact if you take the entire budget for the space programme it is like 0.2-0.3 (percent) of the national budget. So it is very small compared to...others are using even up to 2 or 3%."

GROUND SEGMENT FOR CHANDRAYAAN-1 MISSION

GROUND SEGMENT FOR CHANDRAYAAN-1 MISSION The Ground Segment for Chandrayaan-1 comprises of three major elements : the Ground Station Network including the Indian Deep Space Network (IDSN), Mission Operations Complex (MOX)and Indian Space Science Data Centre (ISSDC). This trio of ground facility ensures the success of the mission by providing to and fro conduit of communication, securing good health of the spacecraft, maintaining the orbit and attitude to the requirements of the mission and conducting payload operations. The ground segment is also responsible for making the science data available for the Payload Scientists along with auxiliary information, in addition to archiving of payload and spacecraft data. Payload Operation Centres (POCs) also form a part of the Ground Segment. Elements of Ground Segment

ABOUT PSLV-Polar Satellite Launch Vehicle

Polar Satellite Launch Vehicle The Indian Space Research Organisation (ISRO) built its first Polar Satellite Launch Vehicle (PSLV) in the early 90s. The 45 m tall PSLV with a lift-off mass of 295 tonne, had its maiden success on October 15, 1994, when it launched India's IRS-P2 remote sensing satellite into a Polar Sun Synchronous Orbit (SSO) of 820 km altitude. Since its first successful launch in 1994, PSLV has launched nine Indian Remote Sensing satellites as well as two micro satellites HAMSAT and IMS-1 built by ISRO, a recoverable space capsule SRE-1, and fourteen small satellites for foreign customers into polar Sun Synchronous Orbits. Besides, it has launched one Indian meteorological satellite Kalpana-1 into Geosynchronous Transfer Orbit (GTO). PSLV has emerged as ISRO's workhorse launch vehicle and proved its reliability and versatility by scoring continuous successes in launching multiple payloads to both SSO as well as GTO. Considering the maturity of Polar Satellite Launch Vehicle (PSLV) demonstrated through various performances, PSLV is chosen for the first lunar mission. The upgraded version of PSLV viz., PSLV-XL (PSLV-C11) will be used to inject the 1380 kg mass spacecraft into a 255 x 22860 km orbit. PSLV has four stages, using solid and liquid propulsion systems alternately. Six strap-on motors augment the first stage thrust. PSLV-XL is the upgraded version of PSLV. In PSLV-XL, the six strap-on motors carry 4 tonne more propellant compared to PSLV; There is also an increase in the length of each strap-on.

PAYLOAD INFORMATION OF CHANDRAYAAN 1

Scientific Payloads

Chandrayaan-1 is an Indian Mission to the Moon. The indigenously developed payload/ experiments are:

TMC Terrain Mapping stereo Camera (TMC) in the panchromatic band, having 5 m spatial resolution and 20 km swath Read More.. HySI Hyper Spectral Imaging camera (HySI) operating in 400-950 nm bands with a spectral resolution better than 15 nm and spatial resolution of 80 m with a swath of 20 km Read More.. LLRI Lunar Laser Ranging Instrument (LLRI) with height resolution of less than 5 m Read More.. HEX High Energy X-ray spectrometer (HEX) using Cadmium-Zinc-Telluride (CdZnTe) detector in the 30-270 keV energy region with spatial resolution of 33 km Read More.. MIP Moon Impact Probe (MIP) as piggyback on the main orbiter of the Chandrayaan-1 spacecraft, which will impact on the surface of the moon. Read More..

Apart from the above indigenous payloads/experiments, ISRO solicited proposals through an Announcement of Opportunity (AO) from International and Indian Scientific Community for participating in the mission by providing suitable scientific payloads, complementing the overall Chandrayaan-1 scientific objectives. Out of the proposals received, six experiments were selected for inclusion in Chandrayaan-1 mission; two of the AO payloads, C1XS and SARA are developed by ESA jointly with ISRO.

The AO payloads Onboard Chandrayaan-1 are:

C1XS Chandrayaan-1 X-ray Spectrometer (C1XS) through ESA - a collaboration between Rutherford Appleton Laboratory,UK and ISRO Satellite Centre, ISRO. Part of this payload is redesigned by ISRO to suit Chandrayaan-1 scientific objectives. Read More.. SIR-2 Near Infra Red spectrometer (SIR-2) from Max Plank Institute for Solar System Science, through Max-Planck Society, Germany and ESA Read More.. SARA Sub keV Atom Reflecting Analyser (SARA) through ESA, from Swedish Institute of Space Physics, Sweden and Space Physics Laboratory, Vikram Sarabhai Space Centre, ISRO. The digital processing unit of this payload/ experiment is designed and developed by ISRO, while Swedish Institute of Space Physics develops the payload. Read More.. RADOM Radiation Dose Monitor Experiment (RADOM) from Bulgarian Academy of Sciences. Read More.. Mini-SAR Miniature Synthetic Aperture Radar (Mini-SAR) from Applied Physics Laboratory, Johns Hopkins University and Naval Air Warfare Centre, USA through NASA Read More.. M3 Moon Mineralogy Mapper (M3) from Brown University and Jet Propulsion Laboratory, USA through NASA Read More..

Summary of Chandrayaan-1 Prime Science Objectives and Wavelength range coverage

Prime Objectives Payload Search for water-ice MiniSAR, HEX, SARA Chemical Mapping C1XS, HEX Mineralogical Mapping HySI, SIR-2, M3 Topography Mapping LLRI,TMC Radiation Environment RADOM, HEX, C1XS Magnetic Field Mapping SARA Volatile Transport HEX Lunar Atmospheric constituent MIP

CHANDRAYAAN 1 SPACE CRAFT DESCRIPTION

Description Spacecraft for lunar mission is : Cuboid in shape of approximately 1.5 m side. Weighing 1380 kg at launch and 675 kg at lunar orbit. Accommodates eleven science payloads. 3-axis stabilized spacecraft using two star sensors, gyros and four reaction wheels. The power generation would be through a canted single-sided solar array to provide required power during all phases of the mission. This deployable solar array consisting of a single panel generates 750W of peak power. Solar array along with yoke would be stowed on the south deck of the spacecraft in the launch phase. During eclipse, spacecraft will be powered by Lithium ion (Li-Ion) batteries. After deployment, the solar panel plane is canted by 30º to the spacecraft pitch axis. The spacecraft employs a X-band, 0.7m diameter parabolic antenna for payload data transmission. The antenna employs a dual gimbal mechanism to track the earth station when the spacecraft is in lunar orbit. The spacecraft uses a bipropellant integrated propulsion system to reach lunar orbit as well as orbit and attitude maintenance while orbiting the Moon. The propulsion system carries required propellant for a mission life of 2 years, with adequate margin. The Telemetry, Tracking & Command (TTC) communication is in S-band frequency. The scientific payload data transmission is in X-band frequency. The spacecraft has three Solid State Recorders (SSRs) Onboard to record data from various payloads. SSR-1 will store science payload data and has capability of storing 32Gb data. SSR-2 will store science payload data along with spacecraft attitude information (gyro and star sensor), satellite house keeping and other auxiliary data. The storing capacity of SSR-2 is 8Gb. M3 (Moon Mineralogy Mapper) payload has an independent SSR with 10Gb capacity.

CHANDRAYAAN 1 MISSION PROFILE

Mission Sequence

Chandrayaan-1 spacecraft would be launched from the Satish Dhawan Space Centre, SHAR, Sriharikota by PSLV-XL (PSLV-C11) in an highly elliptical initial orbit (IO) with perigee (nearest point to the Earth) of about 257 km and an apogee (farthest point from the Earth) of about 22,858 km. After a few revolutions in the initial orbit, the spacecraft's Liquid Apogee Motor (LAM) firing would be done, when the spacecraft is near perigee, to raise the apogees to 37,421 km and 73,925 km respectively. Subsequently, the LAM is fired to take the Chandrayaan-1 spacecraft to extremely high elliptical orbit with apogees 199,277 km and 269,201 km. Later the spacecraft would be raised to an orbit with 1,019 km perigee and 386,194 km apogee. Once the Chandrayaan-1 spacecraft reaches the vicinity of the Moon, the spacecraft is slowed down sufficiently so as to enable the gravity of the moon capture it into an elliptical orbit (LC). After a careful and detailed observation the height of the spacecraft's orbit will be finally lowered to its intended 100 km circular polar orbit. Following this, the Moon Impact Probe (MIP) would be ejected from Chandrayaan-1 to impact on the lunar surface. Afterwards, all the scientific instruments/payloads are commissioned sequentially and Chandrayaan-1 spacecraft explores the Moon with its array of instruments for two years.