Axiom-4 Mission: A saga of 12 million kilometers and 282 orbits aboard ISS

By R Anil Kumar

Bengaluru/ Houston. The Axiom-04 mission has successfully concluded with the return of ISRO Gaganyatri Shubhanshu Shukla, marking a proud moment both for ISRO and India as he returned after a historic 18-day scientific mission aboard the International Space Station (ISS). Launched on June 25, 2025, aboard the SpaceX Dragon spacecraft, the mission was conducted in collaboration with NASA, Axiom Space, ESA, and other international partners.

National Flag flying high onboard ISS

During his stay aboard the ISS, Shubhanshu Shukla adapted exceptionally well to the microgravity environment. Despite the physical and psychological challenges of spaceflight, he maintained optimal health throughout the mission. He captured a wide array of photographs and videos documenting life and work in orbit.

ISRO-Led Scientific Experiments Completed

Gaganyatri Shubhanshu Shukla completed a suite of seven microgravity experiments developed by Indian research institutions under the Human Space Flight Centre’s (HSFC) coordination. These experiments explored muscle regeneration, algal growth, crop viability, microbial survivability, cognitive performance in space, and the behaviour of cyanobacteria—each aimed at enhancing understanding of human spaceflight and microgravity science.

The experiments are listed below

• Space Microalgae (ICGEB &BRIC-NIPGR, New Delhi): Growth and radiation response of edible algae
• Myogenesis (BRIC-InStem, Bengaluru): Muscle regeneration with supplement treatment
• Sprouts (UAS & IIT Dharwad): Microgravity growth of methi and moong
• Tardigrade (IISc, Bengaluru): Resilience and ageing patterns of tardigrades
• Electronic Displays (IISc, Bengaluru): Cognitive testing with in-flight user interface displays
• Cyanobacteria in Microgravity (ICGEB, New Delhi): Comparative growth and proteomics
• Food Crop Seeds (IIST & KAU, Thiruvananthapuram): Impact of microgravity on seed physiology

All experiments were completed successfully, and samples have been returned for detailed post-flight analysis.

Shubhanshu Shukla worked in close partnership with members of Axiom-04 Crew and Expedition 73, contributing to the daily rhythm of ISS operations and supporting joint science, maintenance, and outreach efforts.

He participated in integrated crew timelines, shared resources aboard the Harmony module, and coordinated multiple crossover activities, fostering international cooperation in space.

Public Engagements

Axiom-04’s public outreach component was an integral part of the mission, connecting India’s space achievements with its citizens and students. These events underscored the importance of inspiring the next generation while celebrating national pride.

Interaction with Hon. Prime Minister

On June 28, 2025, Gaganyatri Shubhanshu Shukla participated in a historic live interaction with Hon. Prime Minister Narendra Modi from aboard the International Space Station.

During the conversation, the Hon. Prime Minister commended Shukla’s contribution to India’s space journey and spoke of the pride the nation feltin seeing its flag represented in orbit.

The broadcast reached millions across India and marked a symbolic milestone in India’s space diplomacy.

Student event at Trivandrum

On July 03, 2025, Gaganyatri Shubhanshu Shukla interacted with school students from Trivandrum and Lucknow through a video link, where he answered many questions on how to become an astronaut and life onboard the International Space Station.

Student event at Lucknow

This was followed by two Amateur Radio on the International Space Station (ARISS) sessions that enabled real-time conversations with school students.

The first session was held on July 4, 2025, with students and engineers at URSC, Bengaluru, where Shukla fielded questions on life in space, daily routines aboard the ISS, and the significance of scientific research in microgravity.

The second session, conducted on July 8, 2025, connected students from seven schools in Northeast India through a coordinated link with NESAC, Meghalaya, providing them with a rare opportunity to speak directly with an Indian astronaut in orbit.

On July 6, 2025, Shukla also held a teleconference with the Chairman of ISRO, updating him on the progress of the Indian science payloads and sharing preliminary observations. The exchange reinforced the strong operational link between ground teams and the astronaut, ensuring real-time alignment of mission objectives.

These engagements not only enhanced visibility of the mission but also served to bridge the gap between India’s space program and its young aspirants, creating lasting inspiration across generations.

Final Mission Phase Events

The formal Farewell Ceremony for the Ax-04 crew was conducted aboard the ISS on July 13, 2025, at approximately 19:25 hrs. IST. Expedition 73 crew members and mission control teams expressed appreciation for the collaborative efforts and marked the occasion with symbolic gestures of international friendship, including commemorative mission patches and final photographs in the Harmony module.

Following the ceremony, the crew proceeded with hatch closure and vehicle ingress, and the SpaceX Dragon spacecraft undocked from the ISS later on 14 July 2025 at 16:45 hrs. IST, beginning its return journey to Earth.

The undocking was carried out with nominal systems performance, monitored by NASA and Axiom Space flight controllers in coordination with SpaceX’s MCC-X in California.

After an Earth-orbiting free flight lasting nearly 22 hours and 30 minutes, the splashdown of Dragon occurred successfully on July 15, 2025, at approximately 15:03 hrsIST in the Pacific Ocean, off the coast of California.

The capsule was recovered promptly by SpaceX’s recovery teams, and Shukla was extracted in stable condition. The mission concluded with nominal deorbit operations and vehicle performance.

Post-Flight Status

Gaganyatri Shubhanshu Shukla is now undergoing a structured post-mission medical evaluation and recovery protocol under the supervision of Axiom Space and ISRO flight surgeons.

This program, spanning seven days, includes cardiovascular assessments, musculoskeletal tests, and psychological debriefs aimed at ensuring full physiological recovery and data capture for future missions.

ISRO Mission Operation team at Johnson Space Centre, Houston

Mission operation exposure

As part of India’s participation in Axiom-04, a dedicated ISRO high-level delegation and Mission Operations Team was deployed to Kennedy Space Centre, Florida, which was led by the Chairman, ISRO and the Secretary, Department of Space, Dr. V Narayanan.

The delegation participated in the launch operations. Initially, the launch was rescheduled multiple times due to technical issues including oxygen leakage in booster stage engine bay. On insistence of ISRO team, oxygen leakage issue was fully resolved leading to safe &successful launch. Later, the delegation moved to the Johnsson Space Centre, Houston, to join in the docking operations.

ISRO delegation with Secretary, Dept. of Space, Dr V. Narayanan at Johnson Space Centre, Houston

The Mission operations team continued to stay in Houston, gaining invaluable first-hand experience in managing human spaceflight operations. The team was embedded alongside NASA and Axiom flight controllers, participating in real-time decision-making, telemetry tracking, crew timeline management, and health monitoring of both the astronaut and the science payloads. This exposure provided critical insights into international crewed mission coordination, emergency response protocols, and the complexities of orbital operations.

This collaborative mission will serve as a vital stepping stone in building India’s own crewed mission operations infrastructure, enhancing readiness for future indigenous human spaceflight programs such as Gaganyaan and the Bhartiya Antariksha Station.

(Images courtesy: AXIOM SPACE)