ISRO Scientist Maps India’s Audacious Journey from Moon Landing to Sample Return Mission
J.A. Kamalakar reveals why Chandrayaan-4 must land precisely in Rajasthan, details sulphur discovery at lunar south pole, and outlines India’s roadmap to space station, Venus mission, and 17-year orbital laboratory, Naresh Theegutla of Neo Science Hub, reports.
“In case we don’t do it properly, our friendly neighbours may take away our property,” quipped Sri J.A. Kamalakar, Former Director at ISRO and Former Professor at ISRO Satellite Centre, discussing the critical re-entry requirements for Chandrayaan-4’s sample return capsule—a mission so complex it requires docking two modules in Earth orbit before journeying to the Moon, collecting 2 kilograms of lunar material, and ensuring the samples land precisely in Rajasthan’s Thar Desert.
Speaking at Session I of the National Conclave on “Lab to Society: Role of Science Communication in Building Viksit Bharat @ 2047” at the B.M. Birla Science Centre on Thursday, Kamalakar—a visionary engineer whose career spans pioneering work on electro-optical systems and whose instruments flew on Chandrayaan-1 and Mars Orbiter Mission—delivered a comprehensive account of India’s planetary exploration achievements while mapping an ambitious roadmap extending to Venus, a permanent space station, and technologies that will define India’s space capabilities for decades.
The session, chaired by Dr. D.N. Reddy, Former Chairman of RAC-DRDO and Former Vice Chancellor of JNTU-Hyderabad, provided the platform for Kamalakar to explain not just what India has achieved in space, but why these missions matter for human survival and civilization itself.
Why Explore: Survival, Resources, and Protection
Kamalakar began by acknowledging his colleague Dr. Seshagiri Rao’s earlier presentation establishing cosmic context. “We are a speck of dust in the universe,” he said, before pivoting to the existential imperatives driving space exploration. “Why do we have to explore deep space? Learn about whatever is around us, the dangers, benefits, and reap benefits from whatever technology which we are developing.”
His first reason was stark: “All our resources are yielding very shortly. In another 50 years, almost all the resources of our Earth will be dwindling, and we need to find ways of actually continuing our entire civilization. So we may have to go to other places or bring the materials in from other sources.”
The evidence is compelling: asteroid mining opportunities, water on the Moon, and “massive evidence of water oceans under the icy layers of Jupiter’s moons,” Kamalakar reported, citing recent findings that expand the possibilities for resource extraction beyond Earth.
His second imperative addressed planetary defense. “Protect Earth from potential hazards posed by extraterrestrial matter. Anything which is 35 meters and above hitting at certain velocity onto our Earth can cause huge damage—an entire city can be wiped out,” he warned.
More than 2,000 potentially hazardous objects have been identified, and space researchers globally are developing countermeasures. “One technique which people talk about is to capture the asteroid using satellite probes, deviate its course using propulsion thrusters. You just capture, dock a system there—with a small variation in your propulsion direction, you can push it into hyperbolic orbits,” Kamalakar explained.
Alternative methods include “high-energy rocket probes to make it into smaller pieces” or “laser guns, either from space or beyond, to make it into smaller pieces.”
His warning was urgent: “If you start doing this today, when the actual hazard is coming, it’s too late. So we need to be prepared for all these things. Exploration will help in doing all this.”
Global Goals, Indian Contributions
Kamalakar outlined the common objectives driving space-faring nations: study Earth from space to advance scientific understanding and improve prediction of climate, weather, and hazards; advance understanding of planetary resources and hazards; discover the origins, structure, evolution, and destiny of the universe; and search for Earth-like planets.
India’s contributions span this entire spectrum: Gaganyaan to support human spaceflight programs and inform future missions to Moon, Mars, and Venus; the Chandrayaan series; XPoSat for X-ray polarimetry; SPADEX for docking technology; and the planned Bharatiya Antariksh Station (BAS), India’s own space station.
Chandrayaan-1: The 380,000-Kilometer Leap
Kamalakar provided insider perspective on Chandrayaan-1’s significance. Until 2008, India had reached only 36,000 kilometers using liquid propulsion for geostationary satellites. “This is the first time in Chandrayaan-1 we had to actually travel to Moon, which is 3.8 lakh [380,000] kilometers.”
The mission achieved crucial firsts: India’s first demonstration of an interplanetary probe, Earth orbit transfer to lunar injection—”very critical, as majority of countries lose their satellites when they try to transfer from Earth’s influence to Moon’s influence, but with the credit of our own scientists, we could achieve this in the first attempt itself.”
Kamalakar revealed his personal involvement: “I am very happy to say that one of the instruments which was flown was directly under my design and guidance—one lunar laser ranging instrument. We have characterized the topography of the Moon for the first time using the laser instrument wherein multiple craters have been evaluated.”
The results surprised him: “Over on Earth, we have the highest point and the lowest point. I myself was personally surprised to see that the highest and lowest point, although the Moon is one-fifth of our volume, has got the highest points and lowest points much higher than our own Earth.”
The mission generated approximately 2.9 million topographic points of the Moon, “useful for all our scientists as data.” Remarkably, “Chandrayaan-1 is still orbiting the Moon, although we don’t have control.”
Mars Orbiter Mission: The D/H Ratio Mystery
India’s Mars Orbiter Mission achieved orbit insertion around the Red Planet—a feat accomplished by few nations on first attempt. The mission carried multiple scientific instruments, including another developed under Kamalakar’s laboratory: “One Lyman Alpha Photometer, a gas cell-based instrument which measures D by H ratio—what we call deuterium and hydrogen ratio.”
This measurement is profoundly significant. “It is a clear-cut informative about the escaping process of the atmosphere, how we lose the water content. Mars was once supposed to be like Earth. So if we know the D by H ratio, how the thing is, maybe we may be able to protect our own planet.”
The mission exceeded expectations dramatically: “Although we planned it only for about a year, the orbiter worked about 5-7 years in fact,” Kamalakar reported. “We have a lot of science data received through the experiment. Many scientists are even now evaluating the data.”
Chandrayaan-2: The Complex Dance of Lunar Alignment
Kamalakar explained why Chandrayaan-2 represented a quantum leap in complexity. “Chandrayaan-1, we just had to go and orbit around Moon, transfer from Earth gravity influence to Moon gravity. But Chandrayaan-2 is a totally different task. Here we wanted to land on the Moon.”
The challenge involves exquisite timing and precision: “We need to first identify the landing site where we want to land. About a month in advance we need to focus our attitude on the orbit of the satellite, control the right ascension in such a way that when we reach the Moon, we capture it so that the first day of illumination happens.”
Why this matters: “Illumination stays only for 14 days at the point of the landing site. We need to align such a way that we actually land on that day. So the entire planning has to happen about a month ago until the Moon and then capture the Moon and capture such a way the first day light on that landing site happens.”
This represents “a very complicated flight dynamics requirement which we planned in Chandrayaan-2.”
The orbiter with multiple payloads worked excellently. “Even today, Chandrayaan-2 is providing excellent science data,” Kamalakar reported. The Vikram lander and Pragyan rover were realized, but “unfortunately, due to one or two small uncertainties in the last moment, we could not land safely. But we were well within the 50-meter zone. What we planned, we reached there, but the lander did not land.”
Chandrayaan-3: Robustness and Redundancy
Learning from Chandrayaan-2, the team made critical changes for Chandrayaan-3. “We reduced the payloads which were there on Chandrayaan-2 orbiter and concentrated purely on improving the lander and the rover part. The entire volume or mass capability by the rocket was transferred from propulsion orbiter module to the lander,” Kamalakar explained.
The improvements were comprehensive: “Special tests were done at different places, multiple sorties using helicopters, crane drop tests, characterizing all the sensors. We actually improved the limits of the operation for the control dynamics as well as new sensors were made like a laser Doppler velocity meter.”
Sensor development began years in advance. “We have to foresee what are the likely requirements of the satellites which are likely to come up for various probes like Venus, SPADEX and other things. Sensor development starts much earlier. In my lab, in fact, we have made some of these sensors.”
The result: “Each of the sensors meticulously worked as planned and provided the required input to the absolute information to the NavIC [Navigation with Indian Constellation], which is the laser-based gyro which actually controls both the position and the velocity. All absolute information at the right time was given, and finally landed on 21st August 2023 at the point where we wanted.”
The Sulphur Discovery
After deployment, the Pragyan rover conducted groundbreaking experiments. “Around that South Pole zone, the best possible two-dimensional photography is now available. We have characterized the entire thing,” Kamalakar reported.
The scientific payloads delivered crucial data: “Three of the experiments on the rover have given science results. For the first time, both the EPICS [Electron-Positron Induced X-ray Spectrometry] as well as the laser-based spectroscopy which was attached to the rover have given science data.”
The most significant finding: “For the first time, we detected sulphur. Sulphur normally shows some volcanic activity around that zone wherever we have landed. So people are analyzing the science data.”
Kamalakar’s assessment was unequivocal: “Chandrayaan-3 was a very successful mission.”
SPADEX: Docking for the Future
Following Chandrayaan-3’s success, ISRO demonstrated critical technology for future missions. “In future we may be requiring docking for various programs. So we started the Space Docking Experiment to demonstrate the rendezvous and docking of two spacecraft in space, demonstrate the controllability of the composite.”
The advantages of in-space docking are numerous: deep space exploration and development, satellite servicing and maintenance, space-based solar power and energy, and in-orbit assembly and manufacturing—all “futuristic opportunities” that SPADEX’s successful demonstration now enables.
Chandrayaan-4: The Sample Return Challenge
Kamalakar’s most detailed discussion centered on Chandrayaan-4, a mission “much more complex than Chandrayaan-3 in the sense not only landing—this is a sample return mission.”
India’s launch vehicle constraints drove creative mission architecture. “Because of limitation of our launch capability of about 5 tons per GTO [Geosynchronous Transfer Orbit], we have configured such a way that we will be having two modules which need to be docked at Earth orbit. They go together and finally we have to land.”
Landing site selection is progressing: “Slowly we are identifying some 4-5 zones of landing zones. We have identified one of the leading ones is the Malapert Mountain at 85 degrees south. We will be trying to land there.”
The return journey involves unprecedented complexity for India’s space program: “After landing, we have to again ascend back, and then it has to dock back in the lunar orbit to the transfer module. The transfer module from there—the content, whatever we have collected, about 2 kg of it—has to be transferred. And the transfer module along with the return module comes back.”
This is where Kamalakar delivered his memorable line about geopolitical precision: “Especially the re-entry module has to be properly kept in the proper way so that we come and land at the Rajasthan Thar Desert. In case we don’t do it properly, our friendly neighbors may take away our property. So we need to be very careful about that.”
The mission profile and return trajectory are being finalized. “Most probably the entire dynamics will be worked out very soon. The tests are being done,” he reported.
Lunar LUPEX: Japan Collaboration
Chandrayaan-5 involves international partnership. “The Lunar Polar Exploration (LUPEX)—it’s a collaboration with Japan. They are providing the rover and the launcher, and we have the lander. So jointly we’ll be doing experiments,” Kamalakar explained, demonstrating India’s growing role in collaborative space exploration.
Bharatiya Antariksh Station: India’s Orbital Laboratory
Perhaps the most ambitious project Kamalakar discussed is the Bharatiya Antariksh Station (BAS). “We have just started the work. BAS-01 work is going on. Here we want to actually dock five modules to make our country’s station.”
The timeline is aggressive: “By 2035 we would like to complete the station assembly.” This comes as “presently only ISS and the Chinese two stations are in orbit, and ISS mostly will be stopping soon.”
BAS-01’s design is advancing: “BAS-01 design is more or less completed and it is getting ready now.”
The technical challenges extend beyond conventional spacecraft: “Other than regular satellite and rocket systems—personal hygiene system, ECLSS [Environmental Control and Life Support System]—anyway Gaganyaan we have done to some extent, but this station, people have to stay for longer.”
The operational concept differs from short-duration missions: “Gaganyaan is only for 10 to 11 days we are planning maximum, whereas the total station is supposed to work for 17 years. The first 10 years will be one by one assembling the modules. There will be cargo missions.”
Kamalakar noted numerous applications for BAS but deferred details “because of lack of time”—though the implications are clear: India is building infrastructure for sustained human presence in space.
Venus: The 470-Degree Challenge
The Venus Orbital Mission represents a different category of technical challenge. “This is much more complex in the sense that 470 degrees is the temperature at Venus, and lots of sulfuric fumes are there. So we need to work on those areas,” Kamalakar explained.
Mission planning is complete: “Venus orbital mission planning is already done. The aerobraking phase will be involved—about 10 months it will take. Finally we will be reaching Venus, and a lot of experiments are planned.”
The environment is unforgiving: “It has 470-degree, very harsh environment. So new technologies have to be developed to reach that,” he concluded, signaling that sensor and materials development is already underway in anticipation of this mission.
The Lab-to-Society Vision
Throughout his presentation, Kamalakar embodied the conclave’s theme by connecting technical achievements to human benefit. Planetary exploration isn’t abstract science—it’s about ensuring civilization’s survival through resource access, protecting Earth from asteroid impacts, understanding climate through comparative planetology, and developing technologies that spin off into terrestrial applications.
His personal involvement in instrument development for Chandrayaan-1 and Mars Orbiter Mission, combined with his role in sensor development for future missions, exemplifies the decades-long commitment required to translate laboratory innovations into space-qualified hardware that functions flawlessly hundreds of thousands of kilometers from Earth.
The lunar laser ranging instrument that characterized the Moon’s topography, the Lyman Alpha Photometer measuring deuterium-to-hydrogen ratios on Mars, the laser Doppler velocity meters enabling Chandrayaan-3’s precise landing—each represents years of development, testing, and refinement before contributing crucial data to humanity’s understanding of the solar system.
A Career Spanning Decades, Missions, and Technologies
Kamalakar’s presentation reflected expertise built over decades at ISRO, where he held critical roles in LEOS (Laboratory for Electro-Optical Systems), the country’s sole laboratory for advanced optics and electro-optical sensors supporting remote sensing and communication satellite programs.
His contributions span the breadth of India’s space program: authoring multiple technical papers on laser transmitter design and development; designing infrared Earth sensors, Sun sensors, and Star sensors for all Indian satellite projects; contributing to total indigenization of these sensors; serving as Instrument Scientist and designer for the lunar altimeter payload for Chandrayaan-1 and the Lyman Alpha photometer for Mars mission; appointment as Professor at ISRO Satellite Centre (ISAC) in Bangalore as chairman of Standing Design Review Committee; association with Chandrayaan-3, space docking experiment, Aditya, and other communication and remote sensing projects.
His role in India’s emerging human spaceflight ecosystem has been vital: as part of ISRO’s technical training team, he helped train Group Captain Shubhanshu Shukla and Group Captain Prasanth Balakrishnan Nair on satellite avionics prior to their mission to the International Space Station—a milestone celebrated by the NTTC Alumni Network as a moment of national pride.
Awards recognizing his contributions include the ISRO Merit Award for Electro Optics; International Academy of Astronautics Achievement Award; Team Excellence Award for Chandrayaan-1; contributions to Chandrayaan-1 Payload instruments, development of Space Grade Laser source, and Lyman Alpha Photometer for MARS mission; C.V. Raman Performance Excellence Award; and Distinguished Alumni Award for Technology Innovation Excellence from NIT Calicut.
About Sri J.A. Kamalakar
Sri J.A. Kamalakar is a distinguished Indian space scientist whose career spans over four decades of pioneering work at the Indian Space Research Organisation (ISRO). A visionary engineer, respected mentor, and prolific contributor to India’s space missions, he completed his B.Tech and M.Tech degrees from National Institute of Technology (NIT) Calicut and NIT Warangal.
Widely recognized for his contributions to electro-optics and electronics instrumentation, Kamalakar held many critical roles in LEOS (Laboratory for Electro-Optical Systems), a unit of ISRO and the only laboratory in the entire country for development of advanced optics and electro-optical sensors for supporting remote sensing and communication satellite programs. He served as Unit Head of this lab until July 2014.
Kamalakar co-authored multiple technical papers on the design and development of laser transmitters for space applications, including QCW Laser Diode Driver Design. He is instrumental in developing a variety of electro-optical sensors—infrared Earth sensors, Sun sensors, Star sensors for all Indian satellite projects—and his efforts have led to total indigenization of these sensors.
He was Instrument Scientist and designer for the lunar altimeter payload for Chandrayaan-1, the first Indian mission to Moon, and also involved in development of Lyman Alpha photometer for Mars mission. Appointed as Professor at ISRO Satellite Centre (ISAC) in Bangalore and as chairman of Standing Design Review Committee at the Satellite Centre, he was associated with important ISRO projects including Chandrayaan-3, space docking experiment, Aditya, and other communication and remote sensing projects.
Kamalakar has played a vital role in India’s emerging human spaceflight ecosystem. As part of ISRO’s technical training team, he helped train Group Captain Shubhanshu Shukla and Group Captain Prasanth Balakrishnan Nair on satellite avionics prior to their mission to the International Space Station (ISS)—a milestone celebrated by the NTTC Alumni Network as a moment of national pride.
His excellence has been recognized through numerous awards including ISRO Merit Award for Electro Optics; International Academy of Astronautics Achievement Award; Chandrayaan-1 Team Excellence Award; contributions to Chandrayaan-1 Payload instruments, development of Space Grade Laser source; contribution to Lyman Alpha Photometer for MARS mission; C.V. Raman Performance Excellence Award; and Distinguished Alumni Award for Technology Innovation Excellence from NIT Calicut.
In his presentation at the National Conclave, Kamalakar demonstrated not only deep technical expertise but the ability to communicate complex space missions in accessible terms—explaining why a sample return mission must land precisely in Rajasthan, how sulphur detection reveals lunar volcanic activity, and why Venus’s 470-degree environment demands entirely new technologies. His career embodies the journey from laboratory innovation to space-qualified instruments generating scientific discoveries that advance human understanding while protecting and benefiting life on Earth.
— NSH Digi Desk
