Mumbai, July 13 -- Astronaut Shubhanshu Shukla will undergo a seven-day rehabilitation programme after his splashdown off the California coast on July 15 as he returns to the Earth after an 18-day stay on board the International Space Station (ISS), the Indian Space Research Organisation said on Saturday. Shukla and three other astronauts - commander Peggy Whitson and mission specialists Slawosz Uznanski-Wisniewski and Tibor Kapu of Poland and Hungary -docked at the ISS on June 26 as part of the commercial Axiom-4 mission. The four astronauts are scheduled to undock from the ISS on Monday, July 14, at 4.35pm IST, the National Aeronautics and Space Administration said in a statement. According to ISRO, following a series of orbital manoeuvres after undocking, Crew Dragon spacecraft is expected to splash down near the coast of California on July 15, 2025, at 3 pm IST. "Post splashdown, the Gaganyatri will undergo a rehabilitation program (about seven days) under supervision of flight surgeon to adapt back to Earth's gravity," Isro said in an update on the Axiom-4 mission. "Isro's flight surgeons are continuously monitoring and ensuring the overall health and fitness of the Gaganyatri through participation in private medical/psychological conferences. Gaganyatri Shubhanshu is in good health and in high spirit," Isro said. 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 the Earth. The ISS is orbiting the 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 the planet's atmosphere for a splashdown off the coast of California. Isro said of the seven homegrown microgravity experiments, four experiments have been successfully completed and three are nearing completion. The four completed include Indian strain of Tardigrades involving survival, revival, reproduction and transcriptome; Myogenesis studying the impact of space environment on human muscle cells; Sprouting of methi & moong seeds with relevance to crew nutrition; Cyanobacteria experiment studying the growth of two varieties with relevance to life support systems....