Susmita Mohanty wears many hats: spaceship designer, serial entrepreneur, and space diplomat. She is co-founder and director-general of Spaceport SARABHAI (S2), India’s first space-focused think-tank, which she founded in 2021. Ms. Mohanty has spent more than 25 years in the international space sector working with the Americans, Europeans, Japanese, Russians, and Indians in various capacities, and is invested in India’s transformation into a developed space economy, gender parity in the space ecosystem, and space sustainability. During an interview in her home in Bengaluru, she spoke to The Hindu about her disappointment with women being excluded from the process of choosing astronauts for the Gaganyaan’s first crewed mission, India’s place among spacefaring nations, and what our fledgling space spart-ups need to thrive. Edited excerpts follow.

Having more women in space, especially in leadership roles, seems important to you. You recently wrote about how no woman was eligible to be considered for Gaganyaan’s debut flight since the candidates were required to be combat pilots of instructor grade, which ruled out women candidates.

My reaction to the all-male Gaganyaan astronaut selection was natural since I grew up in an India where women have always been part of the ISRO [Indian Space Research Organisation] workforce and have taken to science and engineering quite happily. ISRO has a good gender balance. If you talk to women scientists in ISRO, they will tell you they enjoy working there.  Besides, India has the highest number of women pilots in the world. Instead of celebrating that and letting them compete, we are just closing the gate on them. It doesn’t make sense. 

Due to advances in space technologies, flying to space is now accessible to ordinary citizens who haven’t been part of a military environment, which is why you have space tourists. Even if the [Gaganyaan] selection committee wanted to limit the first round to IAF pilots, they could easily have allowed the women IAF pilots to compete.

We have more than a hundred women non-combat (helicopter, transport) pilots because we started accepting women in the IAF [Indian Air Force] 30 years ago, in 1993. A retired IAF friend told me that we now have 19 women combat pilots since we started inducting them in 2016.  Not allowing our women pilots to compete was a huge missed opportunity for India.

I wish I didn’t have to write these articles in the first place. We have women who are qualified, capable, and raring to go. So why shut the gate on them? Stop being gatekeepers, let there be fair play.

Can you talk about your childhood in Ahmedabad, and how it shaped your imagination about space?

I was raised in what I call Sarabhai-and-Gandhi Ahmedabad, [which is] rather different from its contemporary avatar. My school principal was a Gandhian. Local industrial families were engaged in cultural philanthropy and institution building and promoted internationalism.

Among the many great institutions that nurtured my curiosity, creativity, and renaissance-upbringing were the School of Architecture (CEPT), Kanoria Arts Centre, National Institute of Design, Space Applications Centre, Physical Research Laboratory, Centre for Environment Education, Textile Research Association, and the Indian Institute of Management.

In my years since, I have lived in multiple cities in the U.S. and Europe. I have travelled the globe. Never have I come across a city that has so many institutes of excellence in such a small radius. Raised in a milieu of space pioneers and renowned contemporary architects, I was smitten with the idea of space architecture and design.

I was a hyper-motivated kid. While in high-school, armed with a bicycle, my dad’s portable German typewriter, and access to amazing libraries, I started working on design problems of living and working in microgravity. Back then there was no internet. So I would use Indian post to mail design ideas to NASA, the European Space Agency (ESA), and American universities. Some even responded from time to time. That kept me going.

Where does India stand today among spacefaring nations? What is the Indian space economy like compared to other countries, and the country’s potential in space research and exploration?

India has one of the oldest space programs in the world. We did our first sounding rocket launch in November 1963. Getting to a successful Moon landing has taken 60 years of hard work and perseverance with many milestones along the way. We launched our first satellite, Aryabhata, in 1975; had our first successful PSLV launch in 1993; and our first successful GSLV launch in 2001. We launched our first Moon mission in 2008 and Mars mission in 2013.

As an independent young nation, as we started to slowly recover from more than 200 years of colonial plundering, India’s first Prime Minister Jawaharlal Nehru had the foresight to commit a substantial chunk of our meagre funds to science and technology early on. That foundation is fundamental to who and where we are today, as a nation. Any country with an advanced space programme such as ours takes a good half a century to get there. Space technology is complex. 

At international space forum, when I hear anyone refer to India as an ‘emerging space nation’, I flinch. I always insist on setting the record straight. The level of ignorance, even arrogance is often staggering. The old space narrative has a strong Western bias because it was largely shaped by the Cold War and Hollywood films.

India ranks among the top six space-faring countries in terms of space capabilities, the others being the U.S., Russia, China, Japan, and France. If you count Moon landings, then France can be dropped from the list. Soon India will become one of four countries to have independent human spaceflight capability once we launch humans into low-earth orbit.

Some of us are working on crafting a new 21st-century space narrative to reflect the [space] power shift to the eastern hemisphere, with China, India and Japan leading the way.

In 2007, when I decided to leave San Francisco and move back to India, I wrote to my mentor Arthur Clarke about my decision. He wrote back saying, “That is very strategic.” When I asked him why he thought so, he wrote back saying, “Everything began in the East and is going back there.” He cited the example of Chinese alchemists having invented gunpowder and said, “No gunpowder, no rockets.”

As someone passionate about preserving the environment, both our own and in outer space, can you talk about the impact of space debris?

I worry about the Moon because it is back in the cross-hair of human exploration. The Moon’s pristine environment will most surely be impacted adversely by human greed and the need to monetise everything. Space agencies and private companies will not stop at exploration and will likely resort to [mass] extraction of resources. Some countries such as the U.S. and Luxembourg have unilaterally passed laws that will allow their private companies to extract and own space resources. The prospect of space mining is real.

That’s not all. Humans are good at littering – there is proof on earth and in low-earth orbit.

We have made low-earth orbit a dangerous place because of tonnes of debris generated due to human activities. Debris objects can be as small as a chip of paint or as big as a defunct satellite or a discarded solar panel. Debris statistics on the ESA’s website indicate we have around 36,000 objects larger than 10 cm, 1 million objects between 1 cm and 10 cm, and 130 million objects between 1 mm and 1 cm. Orbiting debris moves at 28,000 km/hour, so it packs a punch.

Some space debris burns up as it re-enters the atmosphere, some fall into the ocean, and some onto land. Not all debris re-entries are controlled. For example, NASA had jettisoned a large pallet of old batteries weighing roughly 2.6 tonnes from the orbiting International Space Station [ISS], intending for them to burn up on re-entry. A fragment survived the journey and crashed into a Florida home in March this year.

There are Inter-Agency Space Debris Coordination Committee [IADC] guidelines for post-mission disposal of space hardware, but not everyone follows these procedures

How can space play a role in monitoring the effects of the climate crisis?

Earth observation (EO) satellites don’t just help us monitor global warming and ice melts, they also help tackle the impacts of climate change. For example, my former company Earth2Orbit’s EO analytics business arm had developed models that used satellite imagery and advances in machine-learning analytics for use cases that could make cities ‘climate smart’, for example monitor pollution, heat islands, urban sprawl, underground water.

Further, space technology spin-offs and satellite services have applications that can benefit the environment. Satellite-based systems can be leveraged to help reduce vehicle emissions, make wind turbines more efficient, and help solar cells produce more energy.

Most applications use a cocktail of satellites for telecom, remote sensing, meteorology, and navigation. Companies involved in downstream applications are innovating and creating new services and products to mitigate climate change and to help people, for example farmers and fisher folk, cope with climate change.

I’d like to talk about your journey as a space entrepreneur, and the three start-ups you’ve founded on three continents: MOONFRONT in San Francisco, LIQUIFER in Vienna, and EARTH2ORBIT (E2O) in India. Why did you choose to go the entrepreneurial route?

I began my professional space journey in 1997 with a brief stint at NASA’s Johnson Space Centre. After that, I worked for the ISS programne at Boeing in southern California for almost three years. This gave me an in-depth understanding of how the space industry works.

In 2000, I left Boeing, moved to San Francisco, and started a boutique space consulting firm called MOONFRONT. I decided to become an entrepreneur because when you work for a space agency or a large company, you cannot speak your mind freely. You have to toe the line, more or less. I am the type who likes to ask questions and challenge the status quo.

Four years after MOONFRONT, I co-founded a space architecture and design firm called LIQUIFER with a friend in Vienna. LIQUIFER Systems Group, as it is now called, not only designs space exploration, habitation, and transportation systems but also makes full-scale prototypes and tests them in analogue environments.

In 2008, I moved back to India and started my third venture, EARTH2OBIT (E2O). E2O played a pivotal role in opening up the U.S. launch market for the ISRO’s PSLV rocket. We also developed EO analytics products for crop forecasting and making cities climate-smart.

In 2021, I co-founded India’s first dedicated space think tank. We provide research-based policy guidance to the government, give India an international voice, and push for reforms that can help India become a developed space economy.

There has been a lot of conversation around the privatisation of space in India. We are privatising space launches and are in the process of allowing FDI in the manufacture of satellites. Your thoughts?

Privatising routine satellite and rocket assembly for mature technologies could have started two decades ago. I am told there was reluctance and pushback from the government space agency. The fear of losing control was palpable. The fact that it is finally happening is good news. Not just privatisation but even commercialisation of ISRO-tech has started to get traction.

Broadly speaking, there are three kinds of space companies in India currently: the NewSpace start-ups, legacy companies big and small that have been catering to ISRO’s needs for several decades, and telecom companies such as Jio Satcom and the Bharti Group-backed OneWeb.

The space reforms announced by the Indian government in 2020 mark the beginning of a new phase in India’s space journey. Operationalising those reforms will take time, but it is a move in the right direction. There is now a space regulator called IN-SPACe that is the one-stop interface for space companies seeking licenses, access to environmental test facilities, and other forms of cooperation to get their businesses rolling.

What is missing is funding on the scale you find in developed space economies such as the U.S. SpaceX, for example, would not exist without the billions of taxpayer funds it gets from NASA and the DoD [Department of Defense]. An American EO satellite company’s largest customer is usually the U.S. Department of Agriculture and the National Reconnaissance Office. Similarly, our government needs to become an ‘anchor customer’ for our companies for them to scale and thrive. The government cannot expect our companies to run on private capital.

In 2023, IN-SPACe’s ‘Decadal Vision and Strategy for the Development of the Indian Space Economy’ claimed it will propel India’s fledgling space industry from $8.2 billion currently to $44 billion by 2033. The reality is quite humbling. In 2023, cumulatively our [250 or so] space start-ups raised a meagre $134 million.

This February, the government announced FDI [foreign direct investment] liberalisation for the space sector. The FDI money will come in only when we have absolute regulatory clarity, a somewhat evolved space insurance landscape, and better protection of intellectual property. We also need national space legislation, which is yet to happen. So there is a long way to go. We are just getting started.

NASA chief Bill Nelson.
| Photo Credit: AP

NASA administrator Bill Nelson has said that the U.S. space agency will expand collaboration with India and it will include a “joint effort” aboard the International Space Station with an Indian astronaut.

Mr. Nelson’s comments came after a fact sheet issued by the U.S. and India after the iCET Dialogue between U.S. National Security Adviser Jake Sullivan and National Security Advisor Ajit Doval on June 17 said they were working toward commencing advanced training for ISRO astronauts in the U.S.

“Building on my visit to India last year, NASA continues to further the United States and India initiative on Critical and Emerging Technology for the benefit of humanity. Together we are expanding our countries’ collaboration in space, to include a joint effort aboard the International Space Station with an ISRO astronaut,” Mr. Nelson, wrote on X on June 19.

“While specific details about the mission are still in work, these efforts will support future human spaceflight and improve life here on Earth,” Mr. Nelson said.

In New Delhi, Mr. Sullivan and Mr. Doval on June 17 said they concluded the Strategic Framework for Human Spaceflight Cooperation to deepen interoperability in space and are working toward commencing advanced training for ISRO astronauts at the NASA Johnson Space Centre.

The two leaders exchanged views on securing a carrier for the first-ever joint effort between NASA and Indian Space Research Organisation (ISRO) astronauts at the International Space Station, which will mark a significant milestone in the India-U.S. space partnership and space exploration.

They also noted that the space agencies of the two countries are preparing for the launch of the NASA-ISRO Synthetic Aperture Radar, a jointly developed satellite that will map the entirety of the Earth’s surface twice every 12 days as part of efforts to combat climate change and other global challenges together.

The meeting between Mr. Sullivan and Mr. Doval also concluded that India and the U.S. must remain at the forefront of developing critical technologies as part of a larger strategic interest.

Mr. Doval and his counterpart also unveiled a raft of transformative initiatives to deepen India-U.S. cooperation in areas of artificial intelligence, semiconductor, critical minerals, advanced telecommunication and defence space.

The iCET was launched by Prime Minister Narendra Modi and U.S. President Joe Biden in May 2022 to forge greater collaboration between India and the U.S. in areas of critical technologies.

Mr. Sullivan visited Delhi from June 17 to 18, the first trip to India by a senior Biden Administration official after the Modi government came to power for the third term.

The U.S. National Security Adviser was accompanied by a high-level delegation comprising senior U.S. government officials and industry leaders.

The story so far: In the pre-dawn hours (IST) of June 4, a small spacecraft bearing lunar samples took off from the moon’s far side, headed for an orbit that would bring it in contact with an orbiter waiting for it. There, the spacecraft will ‘hand over’ the samples to a capsule on the returner, which will eventually bring the samples back to the earth in a two-week journey. Thus, scientists will finally have access to the first pieces of moon soil and rocks from its far side. All the spacecraft in this mission are part of China’s ambitious and ongoing Chang’e 6 mission.

What are the Chang’e missions?

China’s moon missions are called Chang’e, named for the goddess of the moon in Chinese mythology.

The China National Space Administration (CNSA) launched the Chinese Lunar Exploration Programme (CLEP) in 2003, and the first Chang’e mission happened in 2007. Chang’e 1 created a map of the moon’s surface.

With Chang’e 2, CLEP launched phase I of its moon missions, and equipped the orbiter with a better camera. The images taken by this camera were used to prepare the Chang’e 3 mission’s lander and rover for their descent on the moon, which they successfully achieved on December 14, 2013, and started CLEP’s phase II missions.

Chang’e 4 was a precursor to Chang’e 6: in 2019, it carried the first lander and the rover to descend on the moon’s far side and explore this relatively more mysterious region. Achieving this first required another spacecraft around the moon that could ‘talk’ between ground stations on the earth and the moon’s far side. In the same year, CLEP said China would land an astronaut on the moon in a decade.

Phase III began with the Chang’e 5 mission. In late 2020, it deployed a lander on the moon’s near side. It included a mission component called an ascender, which, after collecting and stowing soil samples (specifically, the youngest volcanic lunar soil samples yet), launched itself into orbit. There, an orbiter collected the samples, transferred them to a returner, and the returner brought them to the earth.

As CLEP’s second phase III mission, Chang’e 6 is attempting to replicate its predecessor’s feat — except from the moon’s far side. This time, the scientific goal is to understand why the far side is so different from the near side.

What is the far side?

The moon is tidally locked to the earth: the lunar hemisphere facing the earth will always face the earth, and the hemisphere facing away will always face away. The far side has rockier terrain and fewer smooth plains than the near side. Scientists believe this is because of heat released by the earth when the moon was forming and thermochemical characteristics of the moon’s near-side surface.

In effect, it’s harder to land a spacecraft on the far side — and more so since it’s impossible to communicate directly from the earth with a spacecraft here: there’s no line of sight. A typical workaround is to have a second spacecraft in space that relays signals between ground stations on the earth and the surface spacecraft, making the mission more complex.

The earth screens the moon’s far side from the solar wind, which is expected to have allowed the far side to retain more helium-3. There has been some excitement in the past about using this isotope in advanced fusion reactors — not least when former Indian Space Research Organisation (ISRO) chairman K. Sivan said as much in a 2018 statement. But the technology for this fusion doesn’t yet exist.

The far side is also expected to be a good place to install large telescopes, which would have a view of the universe unobstructed by the earth. ISRO and scientists at the Raman Research Institute, Bengaluru, are currently working on such a telescope, called PRATUSH.

What is the status of Chang’e 6?

CNSA launched the 8.3-tonne Chang’e 6 orbiter-lander assembly on May 3, and it entered a lunar orbit on May 8. On May 30, the lander complex split from the orbiter and descended over a large crater called the Apollo Basin on June 1. Apollo itself lies within the much larger South Pole-Aitken Basin.

CLEP scientists coordinated this part of the mission with help from the Queqiao 2 relay satellite, which the CNSA launched in February this year into an elliptical orbit around the moon. Its other relay satellite, Queqiao 1, is in a halo orbit around the second earth-moon Lagrange point. (Note: Aditya-L1 is in a halo orbit around the second earth-Sun Lagrange point.)

Once down and operational in the Apollo Basin, a drill plunged into the soil, and with help from a scoop extracted about 2 kg of far-side material, and transferred it to the ascender. On June 4, the ascender took off for moon orbit, where it’s expected to rendezvous with the orbiter, transfer the samples to a capsule in the returner, which is finally expected to return to the earth, crashing somewhere in Inner Mongolia on June 25.

What might the samples reveal?

Since Chang’e 6 is a Chinese mission, the ‘what’ depends on the samples as much as ‘by whom’ and ‘when’. CNSA hasn’t been sharing periodic and detailed updates, as has been expected from other space programmes.

Once CNSA retrieves the sample-bearing capsule, Chinese scientists will have first crack at it before sharing access with foreign research groups based on their proposals. It’s unknown whether any Indian research groups have applied for access.

Scientifically, the far-side samples are expected to inform insights about why the moon is the way it is and the formation of planets.

When it completed the Chang’e 5 mission, China became the first country to successfully execute a robotic lunar sample-return mission since the Soviet Union did in 1976. China was also the first country to execute an autonomous soft-landing on the moon’s far side with its Chang’e 4 mission and — if the returner brings the samples safely back to the earth — will become the first and only country to do so from the moon’s far side as well.

CNSA is expected to launch asteroid and Mars sample-return missions in 2025 and 2030, respectively.

India currently has no plans to explore the moon’s far side. ISRO’s Chandrayaan programme is expected to launch a lunar sample-return mission in 2028, but that is likely to be delayed. India is a signatory of the U.S.-led Artemis Accords, an arrangement that’s expected to have India and other accord members share knowhow to more cooperatively explore the moon next decade.

China is not a part of the accords.

(The details in this article are as of 4 pm on June 6, 2024.)

The test launch of the Agnibaan rocket from the Satish Dhawan Space Centre SHAR, in Sriharikota on May 30.
| Photo Credit: ANI

The Indian Space Research Organisation has said that it has been extending its technical support and sharing its expertise to facilitate a vibrant space ecosystem in India.

Days after the successful launch of the suborbital mission Agnibaan SOrTeD, conducted by Indian start-up M/s Agnikul Cosmos, the space agency said its support for the recent mission showcases the organisation’s willingness to support and nurture private start-ups in India’s space sector.

“For the Agnibaan mission, Satish Dhawan Space Centre SHAR (SDSC SHAR), Sriharikota, supported the selection of a suitable site for suborbital flight and assisted in setting up the Launchpad and Control Centre. A robust network for seamless data and communication between the launch pad, the Control Centre, and the ISRO Control Centre was facilitated,” ISRO said.

It added that SHAR developed comprehensive safety plans and procedures to ensure all operations are conducted safely and efficiently.

“They coordinated launch clearances and NOTAM for all launch attempts and provided extensive range systems, including tracking, timing, real-time data processing, and master control operations. Additionally, SHAR supplied historical wind data for flight planning and real-time atmospheric data for launch commit criteria, alongside crucial logistics support for system realization and launch campaigns,” it added.

It said that the Vikram Sarabhai Space Centre (VSSC) provided its expertise and facilitated 15-second hot testing of the semi-cryogenic engine.

“They conducted acoustic tests for the launch vehicle’s inter-tank structure at CSIR-NAL’s state-of-the-art acoustic testing facility. The mission design underwent thorough verification and validation by VSSC,” it said.

VSSC provided a comprehensive end-to-end Flight Termination System, including pyro charges, batteries, telecommand decoders, and tracking transponders, ensuring the mission’s range safety. It extended on-site support for assembly, integration, wiring, and last-minute pyro operations during the launch campaign, pre-countdown, and countdown phases.

ISRO Telemetry Tracking and Command Network (ISTRAC) provided telemetry and tracking support for this launch through a Memorandum of Understanding with the start-up. Detailed discussions between the teams led to the finalization of critical systems, including the onboard telemetry system configuration and the tracking ground station network. ISTRAC supported the launch campaign from its two ground stations at Sriharikota, offering integration, testing, and real-time tracking. They developed and deployed Vehicle Data Acquisition software to filter real-time data flow to the control centre and display systems. On the day of launch, ISTRAC’s ground station network provided real-time support, confirming the successful launch.

The story so far: The Indian Space Research Organisation (ISRO) has said its PSLV-C58/XPoSat mission has practically left zero debris in earth’s orbit. The space agency explained that the last stage of the Polar Satellite Launch vehicle (PSLV) used in the mission was transformed into a kind of orbital station — called the PSLV Orbital Experimental Module-3 (POEM-3) — before it was left to re-enter the earth’s atmosphere instead of floating in orbit once its mission was completed.

ISRO said that after it completed the primary mission of injecting all satellites into their target orbits, the fourth stage of the PSLV was transformed into the POEM-3. It was subsequently de-orbited from 650 kilometres to 350 kilometres, rendering it more susceptible to being pulled towards the earth and burning up in the atmosphere. ISRO also said it “passivated the stage,” meaning dumped its fuel, to avoid an explosion that could have flung small pieces of debris into orbit.

What is POEM?

Developed by the Vikram Sarabhai Space Centre (VSSC) as an inexpensive space platform, POEM uses the spent fourth stage of a PSLV rocket as an orbital platform. Used for the first time in the PSLV-C53 mission in June 2022, ISRO had POEM orbit the earth as a stabilised platform to perform in-orbit scientific experiments with various payloads.

POEM is powered by solar panels mounted on the fuel tank of the rocket’s fourth stage and a lithium-ion (Li-ion) battery. It has a dedicated navigation, guidance, and control (NGC) system to stabilise its altitude along with helium control thrusters. The NGC system has four Sun sensors, a magnetometer, and gyroscopes, and talks to ISRO’s NavIC satellite constellation for navigation. POEM also has a telecommand system to communicate with the ground station.

ISRO first demonstrated the reuse of the spent fourth stage of its rocket in its PSLV C-44 mission in 2019. After satellites were injected in the target orbits, the fourth stage, carrying a student payload called Kalamsat-V2, was moved to a higher circular orbit of 443 km and stayed there, allowing the payload to make observations.

What has POEM-3 achieved?

ISRO launched the PSLV C-58 mission from the Satish Dhawan Space Centre in Sriharikota on January 1, 2024. After deploying the XpoSat satellite in its desired orbit of 650 km, the fourth stage, now called POEM-3, was lowered to a 350-km high circular orbit. The lower a satellite is in orbit around the earth, the more drag it experiences and the more energy it needs to expend to stay in orbit.

POEM-3 featured nine payloads: two each from VSSC and Bellatrix Aerospace Pvt Ltd, one each from the start-ups TakeMe2Space, Inspecity Space Labs Pvt Ltd., Dhruva Space, and from LBS Institute of Technology, KJ Somaiya Institute of Technology, and ISRO’s Physics Research Laboratory, Ahmedabad.

POEM-3 completed 400 orbits around the earth by its 25th day. The payloads were operationalised to perform their experiments during this time. ARKA200, RUDRA, and LEAP-TD completed their respective experiments while the data from WeSAT, RSEM, and DEX were collected after every orbit for further analysis on the ground. Two fuel cells from VSSC demonstrated their ability to generate power. By January 27, 2024, all of POEM-3’s payload objectives were completed.

For two months, POEM-3 prepared for its re-entry while ISRO tracked it with its Telemetry, Tracking and Command Network (ISTRAC) stations in Bengaluru, Lucknow, Mauritius, Sriharikota, Port Blair, Thiruvananthapuram, Brunei, and Biak (Indonesia) and the Multi-Object Tracking Radar (MOTR) at Sriharikota. On March 21, POEM-3 reentered the earth’s atmosphere, meeting its fiery end.

Why is this significant?

With the rise in the number of satellites in orbit around the earth, space debris has become a pressing issue. Space debris in the low earth orbit (LEO) mainly comprises pieces of spacecraft, rockets, and defunct satellites, and the fragments of objects that have deteriorated explosively as a result of anti-satellite missile tests. This debris often flies around at high speeds of up to 27,000 kilometres per hour. Due to their sheer volume and momentum, they pose a risk to several space assets.

The LEO extends from 100 km above the earth’s surface up to 2000 km above. It includes satellites tracking intelligence data, encrypted communication, and navigation. According to ISRO’s Space Situational Assessment report 2022, the world placed 2,533 objects in space in 179 launches in 2022, up from 1860 objects in 135 launches in 2021.

Also Read | Sign of the future: On ISRO’s PSLV C58 mission

Debris also exists, but in smaller volumes, in the geosynchronous orbit (GEO), which is 36,000 km above the earth’s surface. Currently, there are 7,000 operational satellites orbiting the earth at different altitudes along with millions of pieces of space debris. The U.S. Space Command tracks and catalogues space debris larger than 10 centimetres in LEO and larger than 0.3-1 metres in GEO.

In 2022, four on-orbit break-up events occurred, contributing to most of the debris created that year:

1. March 2022: Intentional destruction of Russia’s Cosmos 1048 in an anti-satellite test adding 1408 fragments of debris
2. July 2022: Break-up of the upper stage of Japanese H-2A while deploying GOSAT-2 satellite adding 52 fragments of debris
3. November 2022: Accidental explosion of the upper stage of China’s Yunhai-3 adding 533 pieces of debris
4. November 2022: Break up of the Japanese H-2A upper stage for the deployment of GCOM satellite adding 30 pieces of debris

The latest incident of space debris causing havoc was recorded on March 8 when a chunk of metal believed to be a discarded battery pallet from the International Space Station ripped through the roof and two stories of a house in Florida. The cylindrical piece, weighing almost 1 kilogram, was recorded by the US Space Command while re-entering the Earth’s atmosphere over the Gulf of Mexico, on a path towards south-west Florida at 2.29 PM that day. Five minutes later, the security camera of the house caught the sound of the metal crashing into it. NASA is still investigating the incident.

A major contributor to the rising number of satellites is American launch-services provider company Space X, which is currently also building a large constellation of 12,000 satellites to provide internet services worldwide. The project, named Starlink, has deployed satellites in 550 km, 540-570 km, and 335-345 km orbits and is expected to be completed by 2027. SpaceX has also applied for a second generation of Starlink satellites comprising 30,000 LEO satellites.

As more communication satellites/constellations are launched and more anti-satellite tests are conducted, more on-orbit breakup and collisions occur, producing smaller and smaller fragments in orbit. The number of space objects (debris or functional equipment) greater than 10 cm in size in LEO is expected to be about 60,000 by 2030, per ISRO estimates. Space debris also leads to two major risks – it creates unusable regions of the orbit due to excessive debris, and leads to the ‘Kessler syndrome’ – creation of more debris due to cascading collisions resulting from one collision.

How are space agencies dealing with debris?

Currently, there are no international space laws pertaining to LEO debris. However, most space-exploring nations abide by the Space Debris Mitigation Guidelines 2002 specified by the Inter-Agency Space Debris Coordination Committee (IADC), which the U.N. endorsed in 2007.

The guidelines outline methods to limit accidental collisions in orbit, break-ups during operations, intentional destruction, and post-mission break-ups. They also advise against the long-term presence of spacecraft and launch vehicle orbital stages in LEO and limit their interference in the GEO region.

NASA had instituted its Orbital Debris Program in 1979 to find ways to create less orbital debris and design equipment to track and remove existing debris. Currently, the sixth U.S. Armed forces wing, called the Space Force, tracks space debris and collisions in LEO. However, the agency has not implemented any technology to clean such debris yet; most such ideas are in the conceptual stage.

Similarly, the European Space Agency (ESA) has adopted a ‘Zero Debris charter,’ which includes multiple ways to mitigate space debris. It has also called for zero space debris by 2030 and seeks that other agencies adopt it as well.

On November 5, 2022, China was widely criticised when its rocket Long March 5B plunged into the Pacific Ocean after it broke up upon re-entry. Ranking among one of history’s most damaging break-ups, one of the more than 500 pieces left of the core stage was about 30 metres long and weighed between 17 and 23 tonnes.

Days later, China deployed a large spacecraft designed to de-orbit its defunct spacecraft. The device had a very slim ‘solar sail’ attached to the payload adapter, which when unfolded expanded to a 269 square foot sheet that would push defunct rocket parts towards the earth for faster re-entry

Japan also has a project, called the Commercial Removal of Debris Demonstration (CRD2), to tackle space junk. The Japan Aerospace Exploration Agency (JAXA) has partnered with private space company Astroscale to assess debris in phase I of the programme. In the second phase, JAXA will launch a satellite to approach the debris and rendezvous with it before capturing and removing it from orbit. Currently, JAXA is conducting tests of this craft.

Private companies in both Japan and China are also competing for debris clean-up contracts. Japan’s Astroscale is developing a method to refuel and repair satellites in space, allowing each de-orbiting mission to operate for longer. China’s Origin Space has launched a prototype robot capable of capturing debris with a large net.

India is working to mitigate space debris. Apart from the POEM missions, ISRO has set up a Space Situational Awareness Control Centre to protect its high-value assets from close approaches and collisions with inactive satellites, pieces of orbiting objects, and even near-earth asteroids. An Indian start-up named Manastu Space is working on technologies like in-space refuelling, de-orbiting of old satellites, and satellite life extension.

• ISRO said that after it completed the primary mission of injecting all satellites into their target orbits, the fourth stage of the PSLV was transformed into the POEM-3.
• POEM is powered by by solar panels mounted on the fuel tank of the rocket’s fourth stage and a lithium-ion (Li-ion) battery.
• With the rise in the number of satellites in orbit around the earth, space debris has become a pressing issue.

Astronomers are looking forward to opening a new window on the universe by posting high-resolution telescopes on the moon, and in orbit around it. There are numerous proposals to do this from astronomers around the world — including one from India called PRATUSH.

On the earth, optical telescopes (which collect visible light at longer wavelengths) and radio telescopes (which collect radio waves with the shortest wavelengths) have to peer through layers of the planet’s atmosphere. While it is becoming increasingly difficult for optical instruments to see through the polluted skies, radio telescopes also contend with radio and TV signals adding to the cacophony of the electromagnetic ‘hiss’ from the communications channels used by radar systems, aircraft, and satellites. It also does not help that the earth’s ionosphere blocks radio waves coming from outer space.

A pristine desolation

Scientists tried to find a way out of this by launching radio telescopes into orbit around the earth. But this only made the problem worse, as orbiting telescopes started receiving radio noise from the whole planet along with signals from outer space. So astronomers are now seriously considering an idea they have toyed with since the 1950s: placing optical and radio telescopes on the far side of the moon, which always faces away from the earth.

The pristine, airless desolation of the moon provides optical telescopes crystal-clear seeing conditions throughout the long lunar night, which lasts two weeks at a time. Radio telescopes on the lunar far side will also be protected by a 3,475-km-thick wall — a.k.a. the moon (its diameter is 3,476 km) — that blots out radio transmissions from the earth and electrically charged plasma winds blowing from the Sun.

In the past, the enormous costs involved discouraged scientists from setting up lunar telescopes. But renewed interest among spacefaring nations to return to the moon promises to open up “the most radio-quiet location in the solar system”, to quote The Royal Society, to astronomers.

The oldest light in the universe

Once upon a time, cosmologists believe, everything in the cosmos was condensed into an infinitesimally small, incredibly dense blob in the void that exploded with a ‘Big Bang’. The resulting fireball cooled as it spread and its blinding light faded into a gathering darkness. At some point, the young universe resembled a formless sea of murky matter, highlighted only by traces of primordial hydrogen and helium.

This darkness persisted from some 300,000 to half a billion years after the Big Bang, which is why there is so little direct evidence today of this important period in the cosmic story. The blackness in the heavens was banished only when the first stars switched on their nuclear power-plants and the cosmos continued to expand. We see this expansion now as a faint glow called the cosmic microwave background (CMB) — the oldest light in the universe — which can be captured by radio telescopes.

Meanwhile, the universe went ‘quiet’ for tens of millions of years afterwards as gravity began to build the first stars and galaxies. This period of time between the initial scattering of the CMB radiation and the birth of the first stars is known as the Dark Ages. It is believed the neutral hydrogen pervading the cosmos during the Dark Ages absorbed some of the CMB radiation to produce an extremely small dip in the frequency of the spreading radio waves.

China may be the first, again

Terrestrial instruments can’t detect this minute frequency drop. Instead, moon-based instruments are our best bet to spot this signal from the Dark Ages, which would be essentially free from the influence of any starlight (since there were no stars then).

“We want to study the Dark Ages period because it connects how the early universe evolved into the universe we see today,” Aritogi Suzuki, who heads the Lunar Surface Electromagnetic Experiment, or LuSEE Night, a joint NASA-Berkeley Lab project, scheduled for launch in December 2025, told this author via email. “We are going to land on the far side of the moon, near the equator of the moon, and almost exactly opposite from the earth. This location is helpful because it best shields radio frequency noise coming from the earth.”

LuSEE Night will be followed by many moon-bound instruments currently in various stages of planning with space agencies like NASA and the European Space Agency (ESA). NASA’s Long-Baseline Optical Imaging Interferometer, for instance, is scheduled to be launched in parts before this decade is out. Once assembled on the moon’s far side, it will study magnetic activity on stars and the centres of active galaxies in visible and ultraviolet wavelengths.

ESA is getting ready to launch a radio telescope to the moon’s far side on board its lunar lander, ‘Argonaut’, by 2030. Other European projects on the anvil include super-sensitive detectors to hunt for the elusive ripples of gravitational waves in space-time and an infrared telescope located inside a permanently shadowed crater near the lunar south pole.

First off the block, however, could be China, with a moon-orbiting radio telescope scheduled for launch in 2026. Another of its satellites, Queqiao-2, intended as a communications relay between the earth and future missions, probably entered into orbit around the moon on March 24. Its payload includes a 4.2-m antenna that will be used as, among other things, a radio telescope.

PRATUSH radio telescope

Although the technologies for these instruments exist, it is difficult for scientists to deploy them on the moon. “An alternative approach,” Dr. Suzuki said, “would be to orbit … the moon instead of landing on the surface and study the data when the satellite is behind the moon.”

This is what Indian scientists plan to do with the radio telescope PRATUSH (Probing ReionizATion of the Universe using Signal from Hydrogen), to be sited on the moon’s far side. PRATUSH is being built by the Raman Research Institute (RRI) in Bengaluru with active collaboration from the Indian Space Research Organisation (ISRO).

Initially, ISRO will place PRATUSH into orbit around the earth. After some fine-tuning, the space agency will launch it moonwards. “Although earth orbit will have significant radio frequency interference (RFI), it will have advantages compared to ground-based experiments, such as operating in free space and lesser ionosphere impact,” Mayuri S. Rao and Saurabh Singh, principal investigators at RRI, explained in an email. “PRATUSH in lunar orbit will have the ideal observing conditions operating in free space with minimal RFI and no ionosphere to speak of.” It will carry a wideband frequency-independent antenna, a self-calibrating analog receiver and a digital correlator to catch radio noise in the all-important signal from the Dark Ages.

As astronomers open new windows from the moon to look at the far reaches of the universe, who knows what discoveries await them. One thing is certain: they are in for some exciting times as the cosmos yields clues to some of its greatest mysteries, such as dark energy (which pushes the universe in every direction at an accelerating rate), primordial black holes and, indeed, the very nature of the cosmos.

Prakash Chandra is a science writer.

The training modules will comprise introductory level topics on various verticals of space science and technology.
| Photo Credit: Visual Generation Inc.

The Indian Space Research Organisation (ISRO) will conduct the Space science and Technology Awareness Training (START) 2024 programme during April and May.

In this connection, ISRO solicits Expression of Interest (EOI) to host START-2024 in educational institutes, universities, colleges within India who are offering UG and PG courses in physical sciences and technology.

The main objective of the training programme is to attract the youngsters to the fields of space science and technology.

The training modules will comprise introductory level topics on various verticals of space science and technology. In addition to these, there will be sessions on Indian space exploration programmes and research opportunities.

Post-graduate students and final year undergraduate students of physical sciences (Physics and Chemistry) and technology (e.g. Electronics, Computer Science, Mechanical, Applied Physics, Radiophysics, Optics & Opto-electronics, Instrumentation and other associated subjects) studying in educational institutes, universities and colleges within India are eligible to be considered for the training.

Last date for online registration of EOI through https://jigyasa.iirs.gov.in/START by institutes, colleges, universities is April 2.

Student registration opens on April 8 and ends on April 12.

Pushpak making an autonomous landing on the ATR runway at Chitradurga.
| Photo Credit: ISRO

The Indian Space Research Organisation (ISRO) has successfully conducted the Pushpak Reusable Landing Vehicle (RLV) LEX 02 landing experiment at the Aeronautical Test Range in Chitradurga on Friday, March 22, 2024.

The RLV LEX 02 landing experiment is the second of the series of experiments conducted by the space agency.

The test was conducted at 7.10 am on Friday, March 22, 2024.

“RLV-LEX-02 Experiment:ISRO nails it again! Pushpak (RLV-TD), the winged vehicle, landed autonomously with precision on the runway after being released from an off-nominal position,” ISRO posted on X (formerly Twitter).

ISRO said that after first the RLV-LEX-01 mission which was accomplished last year, the RLV-LEX-02 demonstrated the autonomous landing capability of RLV off-nominal initial conditions at the release from a Chinook helicopter. The RLV was made to undertake more difficult amnoeuvers with dispersions, correct both cross-range and down range and land on the runway in a fully autonomous mode.

“The winged vehicle, called Pushpak was lifted by an Indian Air Force Chinook Helicopter and was released from 4.5 km altitude. After release at a distance of 4 km from the runway, Pushpak autonomously approached the runway along with cross-range corrections. It landed precisely on the runway and came to a halt using its brake parachute landing gear brakes and nose wheel steering system,” ISRO said.

ISRO said that the mission successfully simulated the approach and high-speed landing conditions of RLV returning from space.

“With this second mission, ISRO had re-validated the indigenously developed technologies in the areas of navigation, control systems. landing gear and deceleration systems essential for performing high speed autonomous landing of a space returning vehicle,” ISRO said.

It added that the winged body and all flight systems used in RLV-LEX-01 were reused in the RLV-LEX-02 mission after due certification and clearances.

“Hence reuse capability of flight hardware and flight systems is also demonstrated in this mission. Based on observations from RLV-LEX-01, the airframe structure and landing gear were strengthened to tolerate higher landing loads,” ISRO said.

ISRO’s Vikram Sarabhai Space Centre (VSSC) Director Dr. S Unnikrishnan Nair said that through this repeated success, ISRO could master the terminal phase maneuvering, landing and energy management in a fully autonomous mode, which is a critical step towards the future Orbital Re-entry missions.

Thiruvananthapuram:

The Gaganyaan manned space flight mission will launch “Indian astronauts into space from Indian soil on an India-made rocket”, Dr Unnikrishnan Nair, the head of the elite Vikram Sarabhai Space Center in Kerala’s Thiruvananthapuram, told NDTV in a special interview this week.

Expected to cost Rs 9,000 crore, Gaganyaan is a “national mission” that will send four specially chosen and trained male test pilots from the Indian Air Force into space, Dr Nair said.

In an exclusive tour of the country’s main rocket lab, an ultra-secure facility, NDTV was given glimpses of the crew module – in which the four pilot-astronauts will travel into space – and the service module – which will be attached to the former, and the space suits that they will wear.

The crew module, Dr Nair said, is a little over 10 feet in diameter and is configured for three people, but this can be adjusted depending on mission requirements. The space suits were purchased from the Russians as part of a deal to buy the seats, which follow the ‘cradle’ philosophy, he said.

On the test pilots themselves, Dr Nair said, “You know… since they are from the Air Force, they are close to astronauts in terms of key attributes, like quick response time, and have responded well to tests like centrifuge, which subjects them to higher acceleration forces.”

“They are now an astronaut training centre for 13 months for training on survivability in different conditions, and then will be subject to parabolic flight tests. Then they will go to Bengaluru, where a Human Space Flight Centre is set up and will get more training, including physical training.”

The four pilot-astronauts – dubbed ‘India’s Fantastic 4’ – were revealed to the country by Prime Minister Narendra Modi last week; they are Group Captain Prasanth Balakrishnan Nair, Group Captain Ajit Krishnan, Group Captain Angad Pratap and Wing Commander Shubhanshu Shukla.

READ | India’s Fantastic 4: Meet Gaganyaan Astronauts Named By PM

Their training will also include academic courses and detailed instruction on Gaganyaan flight systems, as well as yoga, sources at ISRO, India’s space agency, told NDTV.

READ | Gravity, Flying Practice, Yoga: Training For Gaganyaan Astronauts

Earlier all four also received training at Russia’s Gagarin Cosmonaut Training Centre.

Dr Nair also explained why no women will be part of this historic space flight – because pilot-astronauts are drawn from the ranks of Air Force test pilots. At the time, India has no women in that role.

NDTV Explains | Why No Woman Among 4 Pilots Chosen For Gaganyaan Mission

“When I was HSFC (Human Space Flight Centre) Director, we put this idea to the Air Force. But unfortunately, there were then no women test then. Now, I understand there are women test pilots and I hope they will soon join us,” he said.

Meanwhile, NDTV also met Vyommitra – the robotic (female) humanoid that will fly into space for a test flight ahead of the mission. The launch of Vyommitra – whose name comes from Sanskrit words meaning ‘space’ (‘vyom‘) and ‘friend’ (‘mitra‘) – may be in the third quarter of this year.

READ | Robot Astronaut Vyommitra To Simulate Human Functions In Space

Overall, work is on at full pace for the Gaganyaan mission, which will cost about Rs 9,000 crore, with the four test pilots undergoing special training and the launch vehicle now humanrated, which means its ability to safely carry and return its human occupants has been evaluated and confirmed.

Before the manned flight, though, there must be at least two successful unmanned flights, the first of which, if all goes well, will take place by the middle of, or end of, this year, NDTV was told.

ISRO conducting a hot-fire test of the CE-20 cryogenic engine for the LVM-3 at its test facility in Mahendragiri, Tamil Nadu.
| Photo Credit: ISRO handout

On February 21, the Indian Space Research Organisation (ISRO) reported it had successfully completed human-rating the CE-20 rocket engine ahead of its use in an important test flight later this year of the country’s mission to launch an Indian astronaut to space onboard an Indian rocket. The CE-20 is an indigenous cryogenic engine ISRO developed to use with the GSLV Mk III, now called the LVM-3, launch vehicle. It represents an improvement on the CE-7.5 cryogenic engine and is instrumental to ISRO successfully realising its human spaceflight, a.k.a. Gaganyaan, mission.

Engineers prefer to use liquid fuels for rocket motors because they are less bulky and flow better than solid fuels. Using hydrogen as fuel is also desirable because when it is combusted, it generates the highest exhaust velocity. For example, combusting hydrogen with oxygen as the oxidiser results in an exhaust velocity of 4.5 km/s whereas that produced by unsymmetrical dimethylhydrazine and nitrogen tetroxide — the combination used by the second stage of the PSLV rocket, e.g. — is around 3.4 km/s. This is why hydrogen is a desirable fuel for rocket motors.

A tale of three engines

However, hydrogen in liquid form is not well-behaved: it needs to be maintained at -253 degrees C (and the liquid oxygen at -184 degrees C) and leaks very easily. Engineers need special equipment to store and transport liquid hydrogen and special engines that can use it to power a rocket. These are cryogenic engines.

ISRO has used three cryogenic engines over the years: KVD-1, CE-7.5, and CE-20. The last two are India-made, although the design of the CE-7.5 is based on the KVD-1, which Russia (as the Soviet Union) supplied to India in the early 1980s. The GSLV Mk II launch vehicle uses CE-7.5 engines to power the third stage of its ascent.

The operation of a cryogenic engine requires a cryopump, a device to trap and cool the hydrogen and oxygen to liquid form; special storage tanks; and turbopumps to move the cooled fuel and oxidiser to the engine. The CE-7.5 engine uses the staged-combustion cycle. Here, a small amount of the fuel is combusted in a pre-burner. The resulting heat is used to drive the turbine that powers the turbopump. Once the turbopump has brought the rest of the fuel and oxidiser to the combustion chamber, the hydrogen is combusted to power the main engine plus two vernier thrusters — smaller engines that tweak the rocket’s speed and orientation once it’s in flight. The exhaust from the pre-burner is also routed to the combustion chamber.

The CE-20 engine uses the gas-generator cycle, which discards the exhaust from the pre-burner instead of sending it to the combustion chamber. This reduces fuel efficiency but, importantly for ISRO, makes the CE-20 engine easier to build and test. ISRO has also dropped its vernier thrusters in favour of allowing the engine’s nozzle to make small rotations — or gimbal — to adjust the rocket’s flight path. As a result, while the CE-7.5 engine is lighter and sports higher fuel-use efficiency, the CE-20 engine achieves a higher maximum thrust (~200 kilonewton v. 73.5 kilonewton) with a shorter burn duration.

Maximising minimum reliability

These features support the capabilities of the LVM-3 launch vehicle: from being able to lift up to eight tonnes to the low-earth orbit to being the vehicle of choice for the first Gaganyaan mission, while improving India’s self-sufficiency vis-à-vis launch capabilities and keeping launch costs low.

This said, humans aren’t the same as satellites, and rockets (and engines) that carry humans to space need to be tested more intensively — an exercise called ‘human-rating’. Broadly speaking, human-rating entails processes to verify particular errors, like the failure of a particular component, happen at less than a particular rate. Say a particular valve won’t work as intended once every 1,000 tries. So the valve will need to be tested at least 1,000 times to confirm the failure rate is once per 1,000 and, if required, to make it more reliable.

Since 2011, NASA’s Commercial Crew Programme has required the probability of mission loss when the launch vehicle is ascending or descending to be lower than 1/500 (or 0.2%). Obviously the agency can’t conduct so many test flights before a launch, but it can determine the contributions of different mission components to the overall failure rate and test those components to ensure their minimum reliability is above the corresponding limit. The engine test is one example of such a qualifying exercise.

ISRO said in its February 21 press release that the four CE-20 engines had been hot-fire tested for a cumulative “8,810 seconds against the minimum human rating qualification standard requirement of 6,350 seconds”. (In a cold-flow test, fluids flow through the engine but there’s no combustion or exhaust, whereas there is in a hot-fire test.) Hot-fire tests of this duration will ensure the engine’s performance is within acceptable limits in conditions mimicking those that will transpire during the actual mission.

Formidable legacy

The CE-20 engine is accruing a formidable legacy. Aside from being highly performant, it is also a testament of ISRO’s accomplishments after the U.S.’s sanctions against India in the 1980s. Former ISRO chairman U.R. Rao wrote in his book ‘India’s Rise as a Space Power’ that when NASA was developing a cryogenic engine for its Saturn rockets, it identified 58 types of failure, and that Japan had to conduct more than 500 tests to first qualify its LE-7 engine. 

LVM-3 rockets using the CE-20 in the third stage — where the first stage comprises two solid-fuel boosters and the second stage, two liquid-fuelled Vikas 2 engines — have already launched the Chandrayaan-2 and -3 missions and the 5.8-tonne payload of the commercial OneWeb mission in 2022. Next stop: the first uncrewed Gaganyaan test flight, designated G1, which ISRO has tentatively scheduled for mid-2024.