Experiments, exercise, research mark Axiom-4 crew's final days on ISS

New Delhi: Astronaut Shubhanshu Shukla and the other crew members of the Axiom-4 mission are making the most of their final days on the International Space Station (ISS), pushing forward a wide range of experiments that could shape the future of space exploration.

The SpaceX's Crew Dragon spacecraft, carrying the four-astronaut crew, reached the orbital outpost on June 26 and is scheduled to undock from the ISS no earlier than Monday, July 14, at 7:05 am ET (4:35 pm IST), according to an update on X from Axiom Space, which is spearheading the mission.

Shukla and the three other astronauts are expected to board the spacecraft at 2:25 pm IST, wear their space suits and carry out the necessary tests before they begin their journey to Earth.

The ISS is orbiting Earth at a speed of 28,000 kilometres per hour and the spacecraft will initiate the autonomous undocking process to gradually slow down and re-enter Earth's atmosphere for a splashdown off the coast of California. "The Dragon spacecraft will return with more than 580 pounds of cargo, including NASA hardware and data from over 60 experiments conducted throughout the mission," a statement issued by the National Aeronautics and Space Administration said.

"Enjoying our last few days on the @Space_Station with rehydrated shrimp cocktails and good company! #Ax4," Axiom-4 mission commander Peggy Whitson said in a post on X.

Shukla had brought carrot halwa and mango nectar (aamras) to the party.

On the science experiments front, Shukla worked on the microalgae experiment, deploying and stowing samples that could one day provide food, oxygen and biofuels for deep-space missions, Axiom Space said in a statement.

The resilience of the microalgae makes them a promising asset for sustaining life beyond Earth, it added.

"Exercise research and spacesuit maintenance topped the schedule for the Expedition 73 and Axiom Mission 4 (Ax-4) crews on Thursday," the NASA statement said. The crew also continued the Voyager Displays study, which examines how spaceflight affects eye movement and coordination.

The crew collected data for a study to explore how astronauts perceive and interact with their environment in orbit, which is critical for designing mentally-supportive habitats for long-duration missions.

Another study focussed on cerebral blood flow, investigating how microgravity and elevated carbon dioxide levels affect cardiovascular function, which could later benefit both astronauts and patients on Earth.

Radiation exposure was monitored using the compact Rad Nano Dosimeter, a tool for assessing astronaut safety.

The crew took part in the Acquired Equivalence Test, a cognitive experiment that measures learning and adaptability in space, and supported the PhotonGrav study by collecting brain-activity data to explore neuroadaptive technologies for space and medical applications.