NEW DELHI: The hatch of the SpaceX Dragon spacecraft 'Grace' was closed, and the indicator was aligned, marking the final preparations for the undocking of the Axiom-4 (Ax-4) crew from the International Space Station (ISS) after almost 20 days in space.

The undocking from the space station is set for approximately 4:35 PM IST today.

Group Captain Shubhanshu Shukla, the first Indian astronaut to visit the ISS, who is also part of the crew for the mission, will be piloting the spacecraft. The departure operations have begun for the crew with the hatch closing, and the crew have all entered the spaceship.

From there, undocking will begin at approximately 6:45 am EDT or 4:15 PM IST, with the actual undocking approximately at 7:05 am EDT or 4:30 PM IST.

The Dragon Grace spacecraft will re-enter the Earth's atmosphere and subsequent splashdown off the coast of California in the Pacific Ocean at around 3 PM IST on Tuesday, July 15 after a 22.5-hour return journey.

Ahead of the departure, during a farewell ceremony, ISS Commander Takuya Onishi expressed gratitude and admiration for the crew's contributions, reflecting on the collaborative spirit aboard the ISS.

"Peggy, Shux, Suave, Tibor, we really enjoyed your company and thank you so much for bringing so much joy, excitement, inspiration and other positive ways to make our experience here even better, and your dedication to science and your profession definitely set a new standard for private astronaut missions. We hope you enjoyed your time here and hope that the time you spent here will become unforgettable moments in your life," he said.

Commander Whitson responded to Onishi with gratitude, saying, "We really enjoyed ourselves up here. It was an amazing experience... It's special to work with folks who became our friends, and the camaraderie and teaching were really exceptional."

Earlier on Sunday, Group Captain Shukla delivered a stirring farewell speech from the ISS as the Ax-4 crew prepares for its journey back to Earth.

With a modern twist, he quoted the iconic words of Cosmonaut Rakesh Sharma, the first Indian in space, saying, "Aaj ka Bharat abhi bhi saare jahaan se acha dikhta hai" (Today's India is still more splendid than the entire world)."

The Ax-4 crew, comprising Commander Peggy Whitson, Pilot Shubhanshu Shukla of the Indian Space Research Organisation (ISRO), European Space Agency (ESA) project astronaut Slawosz "Suave" Uznanski-Wisniewski of Poland, and Hungarian to Orbit (HUNOR) astronaut Tibor Kapu, had been actively engaged in research and outreach activities aboard the ISS as part of the mission.

As per NASA, the Dragon spacecraft will return to Earth with more than 580 pounds of cargo, including NASA hardware and data from over 60 experiments conducted during the mission.

Axiom Mission 4 was launched on June 25 aboard a SpaceX Falcon 9 rocket from Launch Complex 39A at NASA's Kennedy Space Centre in Florida. The Dragon spacecraft successfully docked with the ISS on June 26 at 4:05 pm IST, ahead of schedule, connecting to the space-facing port of the station's Harmony module.