The AXIOM-4 mission: India's return to human spaceflight

New Indian Express

3 days ago

The $64 million Axiom-4 (Ax-4) Mission – a collaboration involving Axiom Space, the National Aeronautics and Space Administration (NASA), Indian Space Research Organization (ISRO), and European Space Agency (ESA) – is scheduled to be launched on June 8, 2025, at 6.41 pm (IST) from the Launch Complex 39A of Kennedy Space Centre in Florida. A SpaceX Falcon 9 rocket will launch the SpaceX Dragon spacecraft, which will proceed to the International Space Station (ISS), and dock with it.
On docking, the commander of this commercial mission, Peggy Whitson, a former NASA astronaut and director of human spaceflight at Axiom Space; ISRO astronaut Group Captain Shubhanshu Shukla, who is the mission pilot, and two mission specialists, European Space Agency (ESA) project astronaut Sławosz Uznański-Wiśniewski of Poland and Tibor Kapu of Hungary, will enter the ISS for a 14-day stay, conducting experiments and scientific studies. The experiments aim to advance our understanding of microgravity and its effects on various biological processes.
The Ax-4 Mission will be led by private company Axiom Space to highlight the growing scope of commercial entities in space exploration.
The four mission astronauts will conduct about 60 scientific studies and activities, representing 31 countries, including the US, India, Poland, Hungary, Saudi Arabia, Brazil, Nigeria, UAE, and nations across Europe. The mission is set to break records for the most extensive research and science-related activities conducted on a space mission aboard the ISS, underscoring the mission's global significance and collaborative nature to advance microgravity research in low-Earth orbit (LEO).
Project mandate
The research will investigate how microgravity affects human physiology, including bone and muscle loss, as well as its impact on the human immune system apart from effects of space travel on the human immune system. Additionally, experiments will explore the potential for crop growth in space and the remarkable resilience of tardigrades in extreme environments. These studies are part of the 12 Indian experiments focused on space agriculture, microbial adaptation, and human interaction with technology in space, to be conducted by Gp Capt Shukla.
The mission will also study Tardigrades, also known as 'water bears', a phylum of eight-legged segmented micro-animals, discovered by German zoologist Johann August Ephraim Goeze in 1773, who called them 'Kleiner Wasserbär' or 'little water bear'. Harmless to humans, tardigrades are known for their ability to survive in extreme conditions, and earlier studies have suggested they may provide useful insights for improving human stress and radiation tolerance.
The studies are expected to enhance global knowledge in human research, earth observation, biological, and material sciences, while demonstrating the space research capabilities of the crew's home nations.
On completion of their 14-day mission, the Ax-4 Mission will return to Earth's atmosphere in the SpaceX Dragon spacecraft after detaching from the ISS. After safe descent through the Earth's dense atmosphere using heat shields, the SpaceX Dragon spacecraft will deploy its parachutes to reduce its descent velocity and splash down in the ocean before recovery teams retrieve the crew and the spacecraft.
Mission significance; NASA's role
The significance of the Ax-4 Mission to the ISS is it offers convergence of science, technology, and human innovation that enables research that is not possible on Earth. For more than 24 years, NASA has supported a continuous human presence aboard the ISS orbiting laboratory, through which astronauts have learned to live and work in space for extended periods of time.
The space station is a springboard for developing a low Earth economy. NASA's goal is to achieve a strong economy in low Earth orbit where the agency can purchase services as one of many customers to meet its science and research objectives in microgravity. NASA's commercial strategy for low Earth orbit will provide the government with reliable and safe services at a lower cost, enabling the agency to focus on Artemis missions to the Moon in preparation for Mars while also continuing to use low Earth orbit as a training and proving ground for those deep space missions.
The first private astronaut mission to the station, Axiom-1 Mission, lifted off in April 2022 for a 17-day mission aboard the orbiting laboratory. The Axiom-2 Mission to the ISS, which was also commanded by Peggy Whitson, was launched in May 2023 with four private astronauts who spent eight days in orbit. The most recent private astronaut mission, Axiom-3 Mission, was launched in January 2024, and the crew spent 18 days in the ISS after docking with it.
How India stands to gain
Gp Capt Shukla's inclusion on the Ax-4 Mission marks the return of India's first astronaut to space after Sqdr Ldr Rakesh Sharma's participation in the Soviet InterKosmos mission aboard Soyuz T-11 on April 3, 1984.
Currently, from the Indian standpoint, the Ax-4 Mission is being viewed as a 'precursor' to the country's own Gaganyaan-1 mission scheduled to take off in 2027. The mission will involve ISRO's heavy-lift launcher – Human-rated LVM3, or HLVM3 – launching the orbital module carrying three Indian astronauts to an intended Low Earth Orbit of 400 km for three days, before returning to Earth by splashing down in the ocean and being retrieved by the Indian Navy or the Coast Guard ships. Besides Gp Capt Shukla, three others – Gp Capt Prashanth Balakrishnan Nair, Gp Capt Ajit Krishnan and Gp Capt Angad Prathap – are selected for Gaganyaan manned space mission.
According to ISRO, the Gaganyaan mission is being accomplished through an optimal strategy by considering in-house expertise, experience of Indian industry, intellectual capabilities of Indian academia and research institutions along with cutting-edge technologies available with international agencies.
The prerequisites for Gaganyaan mission include development of many critical technologies including human rated launch vehicle for carrying crew safely to space, life support system to provide an Earth-like environment to the crew in space, crew emergency escape provision and evolving crew management aspects for training, recovery and rehabilitation of crew.
Now, various unmanned precursor missions are planned for demonstrating the technology preparedness levels before carrying out the actual Human Space Flight mission. These demonstrator missions include Integrated Air Drop Test (IADT), Pad Abort Test (PAT) and Test Vehicle (TV) flights. Safety and reliability of all systems will be proven in unmanned missions preceding manned missions.
However, the Ax-4 Mission that will lift-off on June 8 evening will offer India a pre-Gaganyaan manned mission chance for actual participation in a human space mission due to the presence of Group Captain Shukla.
Incidentally, two of ISRO's earlier missions – Space Docking Experiment (SpaDeX) and PS4-Orbital Experiment Module (POEM-4) – add immense value in terms of data for the Gaganyaan mission.
POEM-4, in January this year, marked a first for ISRO with seeds of the popular 'alasande kalu' (or cowpea) sprouting in microgravity conditions in space in just four days on board the POEM-4 platform. SpaDeX is providing valuable data about docking and undocking in space – an exercise that will sharpen skills and knowledge about this very exercise, which Gp Capt Shukla will engage in while docking the SpaceX Dragon Spacecraft with the ISS during the Ax-4 Mission.
In many ways, ISRO, through Gp Capt Shukla's involvement in the mission, is set to gain technical knowhow for India's 2027-scheduled Gaganyaan manned space mission, and future manned space missions, too.