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Chandrayaan - 2


Introduction

The Chandrayaan-2 is an ISRO mission aimed at placing an orbiter around the moon and send a lander with two rovers to its surface in 2016-17 using a GSLV launcher.

According to the ISRO Outcome Budget 2013-14:

"The baseline mission objective of Chandrayaan-2 is to soft land at a suitable site on the lunar surface and carry out in-situ chemical analysis. Chandrayaan-2 is envisaged as a two module configuration comprising of Orbiter Craft module and Lander Craft module. Both the modules 
interfaces mechanically by a inter module adapter. Chandrayaan-2 is planned to be launched onboard GSLV MK II with a lift off mass of 2560 kgs and will carry two rovers each weighing 50 kgs. One Rover is developed by Russian Space Agency and the other at ISRO Satellite Center."

ISRO initially planned to use a Russian lander for the mission. However, following the failure of the Russian Phobos-Grunt, a sample return mission to Phobos (one of the moons of Mars), Roskosmos told ISRO that in order to increase the reliability of their planetary mission they would have to redesign their Moon Lander, resulting in an increase in its mass. Consequently, ROSCOSMOS suggested rescheduling of the Chandrayan-2 mission to either 2015 or in 2017. In case ISRO opted for a 2015 launch, the risk of failure would be higher and the ISRO Moon rover would have to be lighter.

Following the Russian inputs, ISRO invited its former Chairman, Chief Prof UR Rao, to do a program review; he recommended that India should develop its own lander, as the country was capable of realize the Lander module in the next few years. 

Currently the spacecraft is being reconfigured for the proposed Indian Rover and Lander modules. [via PIB]

Collaboration with France, USA

ISRO is seeking assistance from France for developing the lander. It is also collaborating with NASA on the project as a whole. In November 2013, ISRO Chairman K Radhakrishnan told the Business Standard that ISRO and NASA are working together on the Chandrayaan project to explore the Moon, as also on missions to study Mars and Sun. 

“We can have a larger mission; we are able to do that. The next one has to be a more complex mission. A while ago, we, along with the French, carried out a joint project of building a satellite---the Megha-Tropiques. We had also worked with the French to develop two landers. We have carried out a joint study with NASA’s JPL,” Radhakrishnan said.

The ISRO Chairman's reference to two lander probably alludes to the main and standby lander. 

Mission Overview

A major goal of the mission would be demonstrate ISRO's capability to soft-land on the lunar surface.

Chandrayaan-2 mission will be a combo of three discrete spacecrafts - an Orbiter Craft module (OC), a Lander Craft module (LC), and a Rover that piggy backs to the lunar surface on the lander and then drives off to explore the lunar surface surrounding the landing site.

The orbiter and the Lander (with the Rover) would be interfaced mechanically by an inter module adapter. 

The Orbiter Craft will conduct mineralogical and elemental studies of the Moon’s surface from lunar orbit. 

The Lander Craft will soft land on the lunar surface and release the rover.

The scientific payloads on the Lander are yet to be firmed up.

Payload Finalization

The payloads for Chandrayaan-2, as recommended by the Advisory Committee on Space Sciences (ADCOS), was announced by ISRO on Monday, August 30, 2010.

ADCOS is chaired by Prof U R Rao and comprises members are drawn from ISRO centers, academic institutions and R and D laboratories and Chaired by Prof U R Rao, Chairman,

"Inclusion of additional payloads, if possible within the mission constraints, will be considered at a later date following a detailed review", ISRO said in a statement.

Orbiter and Lander in stacked configuration with Rover inside the Lander craft


Lander

At present, the list of possible payloads considered onboard the Lander also includes seismometer. The payloads on the Lander will be finalized in due course taking into account the weight, volume and power constraints of the Lander. 

Orbiter

The orbiter will weigh 1,400 kg.

The five payloads recommended for the orbiter by the Advisory Committee on Space Sciences (ADCOS) are

  1. Large Area Soft X-ray Spectrometer (CLASS) from ISRO Satellite Centre (ISAC), Bangalore and Solar X-ray monitor (XSM) from Physical Research Laboratory (PRL), Ahmedabad for mapping major elements present on the lunar surface. 
  2. L and S band Synthetic Aperture Radar (SAR) from Space Applications Centre (SAC), Ahmedabad for probing the first few tens of metres of the lunar surface for the presence of different constituents, including water ice. SAR is expected to provide further evidence confirming the presence of water ice below the shadowed regions of the moon. 
  3. Imaging IR Spectrometer (IIRS) from SAC, Ahmedabad for mapping of lunar surface over a wide wavelength range for the study of minerals, water molecules and hydroxyl present. 
  4. Neutral Mass Spectrometer (ChACE-2) from Space Physics Laboratory (SPL), Thiruvananthapuram to carry out a detailed study of the lunar exosphere. 
  5. Terrain Mapping Camera-2 (TMC-2) from SAC, Ahmedabad for preparing a three-dimensaional map essential for studying the lunar mineralogy and geology. 

The orbiter will circle the moon at an altitude of 200 km and is being designed for a life of 2 years.

Rover

Artist impression of the Rover

The Rover was initially designed in Russia and was to be fabricated to Russians specs by Indian scientists. After India took up Lander development some obvious tweaks were made to the rover design - It now has six wheels instead of four and it's weight appears to have gone up from 15-kg to 20-kg. It's unlikely though not inconceivable that ISRO trashed the original Russian design of the rover and developed a new design from scratch.

Powered with a small solar panel, the rover features semi-autonomous navigation and hazard avoidance capability. It is built to communicate with Indian Deep Space Network (IDSN) using the Lander Rover Communication System on-board the Lander, or through the Orbiter Rover Communication System on-board the Orbiter. 

The Rover would be loaded with commands for turning to the left and right, for going forward and backward. 

Through the Chandrayan-2 mission, ISRO  scientists hope to hone their deep space communication technology - transmission of commands to the payloads and reception of data collected by them - for future planetary exploration. 

The Rover is built to collect soil samples and analyse them. It would carry two scientific payloads weighing 2-kg:

  1. Laser induced Breakdown Spectroscope (LIBS) from Laboratory for Electro Optic Systems ( LEOS), Bangalore.  (In English, a laser ablation tool for spectral analysis of rocks and soil.)
  2. Alpha Particle Induced X-ray Spectroscope (APIXS) from PRL, Ahmedabad.  
Both instruments are expected to carry out elemental analysis of the lunar surface near the landing site.

The Rover was initially designed to have 4 wheels but following test of a Bread Board Model (BBM) on simulated Lunar terrain at the Terrain Test Facility, ISITE, it has now been decided that the Rover will have six wheels.

In May 2014,  Dr. Annadurai told The Hindu that the rover would move about on the moon for one lunar day (14 earth days.) 

A helium balloon is attached to the rover during tests to simulate reduced weight and traction under lunar gravity. Photo Credit: ISRO [via The Hindu]

The Rover's mobility is being tested a the ISRO Satellite Integration and Testing Establishment (ISITE) in Bangalore. A helium balloon which lifts is attached to the rover during tests. The balloon lifts five-sixths of the rover’s weight to simulate reduced weight and traction under lunar gravity

Anorthosite rock from Sithampoondi and Kunnamalai, about 260-km from Bangalore, has been pulverized and laid out at ISITE. 

The chemical and mechanical properties of the pulverized Anorthosite closely resemble those of lunar soil.

Geologists from Periyar University, Salem; the National Institute of Technology, Tiruchi; the, Indian Institute of Science, Bangalore, and the National Geophysical Research Institute, Hyderabad are collaborating with ISRO on the Chandrayaan-2 project.

S. Anbazhagan, Professor and Head of the Department of Geology, Periyar University, told The Hindu, “We had done spectral studies on the lunar soil and we discovered its equivalent at Sithampoondi."

According to S. Anbazhagan, the moon has two types of rocks — basaltic and anorthosite. The latter covers a vast area of the moon. 



At a Glance
 Launch Date
 2016-17
 Launcher      GSLV
 Total Weight  2,660 kg
 Orbiter Weight  1,400 kg
 Lander Weight
 1,260 kg (35 kg scientific instruments)
 Rover  20 kg (Initially, it was reported that the rover would weigh 15-kg. In May 2014, The Hindu reported the new weight.)

Launch Schedule

On January 9, 2014, following the successful launch of GSLV D5, ISRO Chairman K Radhakrishnan told PTI that Chandrayaan-2 would be launched in 2016-17. 

Elaborating on the schedule, Mr. Radhakrishnan said, “In May 2012, we conducted a feasibility study on development of a lander and this has been completed. We find that we will be able to develop a lander in India. We need 2-3 years time.” 

Mr. Radhakrishnan added that ISRO needed to develop a few technological elements in a lander.

“First, we need to reduce the velocity of a lander as it comes for soft landing. Second, to develop the mechanism that is involved in a lander. Third, is to locate precisely where to land by taking pictures and then steering the lander to a place it has to land.”

Following the successful launch of IRNSS-1A on July 1, 2013, ISRO Chairman K Radhakrishnan told the press ISRO and Roskosmos are discussing the Chandrayaan lander.

“As of now, there is uncertainty over the availability of the lander from Russia. Internal reviews are going on over the failure of the Phobos-Grunt mission. We will have clarity only in about two months over the lander. ISRO is communicating with Russia over the matter,” said Radhakrishnan.

The launch of the spacecraft is scheduled for 2015-16, but is dependent on the GSLV launcher becoming operational again well in time.

ISRO  Chariman K. Radhakrishnan reconfirmed to the press in July 2012 that the Chandrayaan-2 mission could be on its way in 2014. [via The Hindu]

Following the failure of the Russian Phobos-Grunt mission to Mars in November 2011, there were reports in the Russian press that the mission is likely to be rescheduled to 2016. 

However, ISRO's annual report for 2012, released in April 2012, still gives the launch year as 2014.

To begin with, the spacecraft was planned to be launched in 2013 (First Quarter) using a GSLV Mk 3. However, following two consecutive failures of the GSLV launcher on April 15, 2010 and December 25, 2010, ISRO has pushed back the launch by nearly two years, and settled on GSLV Mk 1 as the launcher. 

The Mk. 1 carries a lighter payload than the Mk 3. As a result, ISRO is limiting the experiments being carried on board.

Speaking to the press on September 9, 2011 ISRO Chairman K Radhakrishnan said, “We have to go through design review and then move ahead”. This mission is slated for 2013-14, he added.

As in early September 2011, ISRO was poised to start developing the engineering model its rover for testing with the lunar surface simulator.

Project Director

The project is being helmed by  Dr Mayilsamy Annadurai.

Mission Profile

According to a presentation made by Dr. Goswami and M. Annadurai, project director for Chandrayaan-2, at 2011 Lunar and Planetary Science Conference:

A GSLV Mk-2 launcher will will place the Chandrayaan-2's orbiter, lander and rover, in a transfer orbit around the Earth. From there, the orbiter's onboard rocket engine will propel both the spacecraft and the lander-rover combo into a trajectory that will take them to the Moon.

Once on the lunar transfer trajectory, the orbiter and lander-rover will separate. The two would then journey independently to the Moon, 

Landing Sequence

During the landing, the lander's main engine will bring the spacecraft to hover at approximately 2 kms above the lunar surface and then shut down.

The lander will then free fall under the moon's weak gravity, with small thrusters periodically firing to control the rate of descent.

The lander will use a three beam Doppler radar to avoid large obstacles during its descent to the moon's surface.

The accuracy of the autonomous landing system allows the landing area to be predicted as an ellipse that is 30 km long and 15 km wide.

After the lander touches down on the moon, it will release the rover on the lunar surface. 

Landing Site

Two candidate landing sites near the Lunar south pole have reportedly been identified by the Russians, based on data from NASA's Lunar Reconnaissance Orbiter (LRO) and Japanese Selena orbiter, which entered lunar orbit in 2007.

The Russian developed Lunar Exploration Neutron Detector, LEND, installed on LRO was used to identify sunlit areas, potentially with sub surface ice. Imagery from Selena and data from LOLA laser altimeter on NASA’s LRO orbiter was used to profile the terrain in these areas.

To begin with 14 sites in sunlight areas close to the South Pole that possibly have subsurface ice were identified..

Nine of these sites were rejected at the outset by the lander team because the terrain was too rough for the landing system of the spacecraft.

Selected Sites

Based on accuracy of the landing system, two sites have been short listed

Main site: 87.2 deg S, 68 deg E, Shoemaker, Faustini
Backup site: 88.5 deg S, 297 deg E, Gerlach

The sites finalized could change if the accuracy of the landing system is improved or based on other data.

Spacecraft Redesign

Once it became clear that Chandrayaan-2 would have to be launched by GSLV and not GSLV-III, the structure configuration of the spacecraft was changed from I2K to I3K to accommodate a revision in payload lift off capacity.  The change will facilitate the use of larger propellant
tanks. 

Chandrayaan-2 design evolution


The mission strategy was revised to inject the satellite in a lower initial orbit (170 X 16980 km) with a higher lift-off mass of 3200 kg and the Propulsion System Configuration changed to increase fuel carrying capability of the satellite.

Development Progress

In May 2014, Chandrayaan-2 project director Dr. Annadurai told  The Hindu, "We have realized a six-wheeled rover and it is being tested in the lunar terrain facility. The design work on the lander is in progress in ISRO. Everything about the Chandrayaan-2 mission is Indian. The launch vehicle, the orbiter, the lander and the rover are all from India.”

According to ISRO's annual report for 2011-2012, the tasks completed include finalization of all electrical and mechanical interfaces including the payload interfaces; Preliminary Design Reviews (PDRs) of Bus Systems (Power, Attitude Orbit Control Electronics, Telemetry, Tracking and Command Baseband Systems, RF Systems, Data Handling System, Structure, Thermal Control System, Propulsion System); all systems accommodation studies and initial thermal analysis.

Chandrayaan 2 History

Under an agreement signed on November 12, 2007 between the space agencies of India and Russia, ISRO and Roskosmos, each agency was to contribute Rs 425 crore towards the cost of the mission. The spacecraft was to be launched in 2014, with an orbiter made by ISRO and a lander made by Russian Space Agency Roscosmos. The lander was to carry a small Indian built rover to collect and examine lunar soil samples, Russians refer to the project as Luna-Resource.

Division of Responsibility

According to Government of India press release on August 4, 2010:

"The Chandrayaan-II project is envisaged to have an Indian Orbiter module with scientific instruments to go round the moon and a Russian Lander module carrying an Indian Rover and a few scientific instruments.  

The Chandrayaan-II project will be launched using the Indian Geostationary Launch Vehicle - GSLV.  The costs towards these components will be met by the Space Agencies of the respective countries."

ISRO will launch Chandrayaan 2 using a GSLV Mk-2 rocket and realize the orbiter and rover. Roscosmos will realize the lander that will carry the rover to the moon.

Many other countries (USA, France, Germany, Sweden) are expected to participate in the project by contributing instruments and equipment.

During 2009 ISRO and Russian officials talked of there being two rovers. A large main rover designed in Russia and fabricated in India; and a mini-rover designed and fabricated in India, with both rovers being controlled from India. 

Following a cost analysis, the Russians gave up on their rover in May 2010.

“The tasks of the mission are to investigate rock samples at the maximum distance from the landing point and to confirm the presence of water,” Roscosmos Deputy Head Anatoly Shilov said at the Bengaluru Space Expo in August 31.

While the Indian rover will analyze lunar surface soil, the Russian lander is likely to drill into the lunar surface and analyse sub surface soil.

Phobos Grunt Failure

Following the failure of the Russian Phobos-Grunt mission to Mars in November 2011, there were reports in the Russian press that the mission is likely to be rescheduled to 2016. 

Academician Lev Zelyony, the director of the Institute for Space Research of the Russian Academy of Sciences told Interfax in February 2012 that "the technical solutions used in the Phobos-Grunt project need to be revised. Those solutions were used for the lunar projects too. It does not touch upon the equipment – it goes about spacecraft and control systems." [via Red Orbit]

Roskosmos Dropout

On January 21, 2013, Dr. S.V.S. Murty of the Planetary Exploration Group of the Physical Research Laboratory (PRL), an institution in Ahmedabad under ISRO, announced  that India would undertake the Chandrayaan mission all by itself, dropping earlier plans of collaborating with Russia. [via The Hindu]

Dr. Murty was speaking on India’s lunar and Mars missions at a workshop on exoplanets at the laboratory.

ISRO took the decision to go it alone after Russia's Roskosmos expressed its inability to provide the lander for the mission, following the failure of the Russian Phobos-Grunt mission to Mars in November 2011.

ISRO will now make the orbiter, lander and rover all in-house. 

SAC has completed the design of the indigenous lander and preliminary configuration study, according to Murty. The mission profile has undergone minor alterations.

The Chandrayaan-2 will be launched using a GSLV powered by an indigenous cryogenic engine in 2015.

The Orbiter will have five primary payloads, two of which will be improvements on instruments that were onboard Chandrayaan-1.

The rover too will carry two additional instruments. 

According to PRL director Jitendra Goswami, despite the Russian pull out from the  Chandrayaan project, Indo-Russian collaboration in planetary exploration will continue. 

Chandrayaan 2 was a component of Roskosmos' Luna-Glob moon exploration program. It is possible the Russian agency would collaborate with ISRO in one of its future lunar missions.

Roskosmos Dropout Denial

On January 22, 2013, Physical Research Laboratory (PRL) Director J N Goswami told the press that Chandrayaan 2 would continue to be a joint Indo-Russian project despite the delay.

"The Indo-Russian mission is going ahead. The project has got delayed. Currently, we are whole-heartedly working for the Mars project scheduled for November. The moon mission, for the time being, has got delayed," Goswami told PTI.

"The failure of Roskosmos Phobos-Grunt mission (in December 2011) has, for the time-being, delayed the moon mission," Goswami said, adding the construction of lander for the combined mission has been delayed.

According to PTI, it made repeated attempts to contact  S V S Murty, who had announced the Roskosmo drop out a day earlier, but he was not available for comments on the issue.

GOI Clarifies Current Status of Chandrayaan - 2 

The GOI clarified in the Lok Sabha on February 27, 2013

"In May 2012, ROSCOSMOS has indicated a major programmatic change in Joint Moon Exploration. Currently the discussions are underway between ISRO and ROSCOSMOS on the way forward." [vai PIB Release]

Roskosmos Dropout Confirmation


ISRO's Annual Report for 2012 clarified that ISRO would be developing the Orbiter, Lander and Rover all by itself, but with Russian help.

On August 14, 2013, in reply to a written question in the Rajya Sabha the GOI confirmed that ISRO had decided to undertake the Chandrayaan mission all by itself. [via PIB]

Design Evolution

ISRO announced on Wednesday, December 24, 2008, that the design for Chandrayaan II has been completed and it will be launched by 2012. 

“The designs for Chandrayaan II have been completed and we hope to launch it by 2012,” ISRO chairperson G. Madhavan Nair told reporters on the sidelines of a function organized by the Confederation of Indian Industry (CII) to felicitate the Chandrayaan I team.

Annadurai told the press on January 18, 2009  that Chandrayaan 2 will be launched using a GSLV Mk III. The complete spacecraft will weigh 2,700 kg. 

In a statement to the press on April 20, 2008, following the launch of RISAT 2, TK Alex, director of the ISRO Satellite Center, said that ISRO is finalizing the test equipment that would go with the two rovers that would soft land on the moon. 

On August 16, 2009, ISRO chief G Madhavan Nair announced that a joint review of the design with the Russians had been completed.

"Right now, the design has been completed. We had a joint review with Russian scientists here," he said.

"Next...we will go towards prototype building, which will be taken up next year," Nair said.

On November 7, 2009, while inaugurating the sixth National Student Conference at University Visveswaraya College of Engineering, Annadurai stated that the projected will be completed by 2012-13. 

“Chadrayaan-II will consist of the spacecraft and a landing platform with two moon rovers, one from India and one from Russia, which will land on the moon and move on wheels on the lunar surface, pick up samples of soil or rocks, do a chemical analysis a nd send the data to the spacecraft orbiting above,’’ Dr Annadurai said.

Design Change Following Discovery of Water on the Moon

Buoyed by the widespread presence of water on the moon, ISRO decided to tweak its Chandrayaan-2 rover payload to facilitate sub-surface soil analysis.

One of the two rovers onboard the Chandrayaan-2 lander will be equipped with a a drill capable of collecting samples from a few millimetres below the lunar surface.

"We have a good head start," said then ISRO chairman G Madhavan Nair.

"The data we have is really exciting and we will definitely have to re-visit the mission objectives.

"We may go for certain midcourse correction of the objectives."

On May 9 2010, Annadurai spoke to The Hindu after delivering the keynote address at the graduation ceremony of B. Tech and MBA students, organised by the Toc-H Institute of Science and Technology (TIST), Arakkunnam, near Cochine. 

"The purpose of Chandrayaan-I was to understand what the entire moon contained. But now, the effort would be to understand it in situ. Originally, we wanted to have chemical-mineral analysis, but now that Chandrayaan-I has shown us traces of water on the moon's surface, the emphasis could also be on confirming the finding," he said.

Nuclear Powered Orbiter Considered but Dropped

At one stage ISRO contemplated the use of nuclear power for the lunar orbiter in collaboration with Bhaba Atomic Research Center.

"We are thinking of powering some parts of Chandrayaan II with nuclear power and it will power the spacecraft when it revolves around the dark side of the moon," Madhavan Nair, Chairman, ISRO, told media in early August 2009.

Lander / Rovers

The Chandrayaan 2 will comprise a 1,260 kg Russian designed and developed moon lander carrying a single 15 kg rover developed by ISRO in  collaboration with Russia.

Lander

The 1,2060 kg Russian lander will carry a scientific payload of 35 kg, not including the rover.

It will be powered by solar panels

It will focus on the geochemical analysis of the lunar soil and the detection of water, which was first confirmed from observations made using Chandrayaan - 1.

Russia is considering the use of a drill that could penetrate as much as a meter below the surface to possibly make contact with water.

Besides equipment to analyse the lunar soil and detect the presence of water, the lander will carry a seismometer and a laser reflector. Also being considered is a landing beacon that could facilitate future landings.

Russia plans to test the lander in 2011,  Roscosmos Deputy Head Anatoly Shilov told AW&ST on August 31, 2010

Twin Rovers Considered at One Stage

Early plans envisaged that the moon lander will carry two rovers: A 50 kg Russian rover that will carry the major exploration instruments, and a 15 kg Indian rover, primarily designed to give Indian space scientists experience in robotics and precise remote control over planetary distances, which will separately undertake chemical analysis of the lunar soil.

The 15-kg. (33-lb.), 10-watt, solar-powered Indian rover will include a laser ablation tool for spectral analysis of rocks and soil, and video cameras for navigation. (AW&ST)

Single Rover Finalized

In May 2010, ISRO and Roskosmos dropped plans for a Russian rover, opting for a 15 kg Indian rover..

Rover Development

A significant part of the rover, including its communication package, is being fabricated in Kerala. 

On September 10, 2011, ISRO announced that it is ready to start building an engineering test model of the rover for testing with the lunar surface simulator.

Mobility

IIT Kanpur is developing subsystems to provide mobility to the Indian rover to be placed on the moon by the Chandrayaan-2 lander. 

The components being developed  are: stereophonic camera based 3D vsion, kinematic traction control, and motor dynamics of the rover's six wheels.

The 3D vision component is being developed by Dr. K.S. Venkatesh, Associate Professor of Electrical engineering.

3D vision involves generating structured light based 3D map of lunar terrain, Dr Ashish Dutta, Associate Professor of mechanical engineering at IITK told HT:

“As there is no ready made map of the lunar surface, the focus is to use structured  light to generate a map of the lunar terrain after landing. Based on the map the robot is expected to move from one point to another for experiments.

Kinematics and path planning involves using the generated map to move to  a desired location, choosing the safest path to travel over the lunar terrain which has craters, rocks and dust.

The path chosen should not only be safe but also involve least energy consumption, Dutta said. The  system has to factor in moon's lower (1/6th) gravity and the mandate for zero errors.

The stereo vision cameras will provide the ground team controlling the rovers a 3D view of the surrounding terrain.

The rover will have six wheels each driven by an independent electrical motor. Four of the wheels will also be capable of independent steering. A total of 10 electrical motors will be used for traction and steering.

Kinematic traction control will enable the rover to negotiate the rough lunar terrain using independent steering provided on four of its wheels.

IIT Kanpur reported completing the project in March 2012. [via HT]

The developed systems will now be handed over to ISRO for final testing and evaluation. 

Rover and Lander Test Center

ISRO is setting up a center in Bangalore for testing of the Chandrayaan-2 rovers and lander, which will have a test area mimicking the lunar terrain and conditions. The Russian rover too will be tested there before being fitted to Chandrayaan-2.

Because of recent speculation that the dense packing of 11 payloads in the Chandrayaan lunar orbiter led to its overheating and subsequent loss, ISRO scientists are less keen to invite payloads from outside space agencies or universities. 



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