The trio of NASA astronaut Chris Cassidy and Russian cosmonauts Anatoly Ivanishin and Ivan Vagner, who left for the International Space Station last April, has successfully returned to Earth on Wednesday, October 21.

Leaving the planet on April 9, the crew of the ISS Expedition 63 was the first expedition to launch weeks after the World Health Organization declared the COVID-19 outbreak as a global pandemic on March 11.

Cassidy, who served as the ISS mission commander for the expedition, formally turned over the command of the International Space Station to Sergey Ryzhikov, Russian cosmonaut with the Roscosmos and the mission commander for ISS Expedition 64. The turnover was conducted in a change of command ceremony aboard the space station on Tuesday, October 20.

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Back Home After 196 Days

The crew members of Expedition 63 began the flight back to Earth Wednesday afternoon, officially closing the hatch to the Soyuz spacecraft at around 4:24 PM ET. The hatch closure was delayed because of a camera issue preventing NASA and Roscosmos from capturing the live feed of the event. Three hours later, the Soyuz capsule undocked at 7:32 PM ET and after another three hours, at exactly 10:54 PM ET, landed on the remote town of Dzhezkazgan, Kazakhstan.

After sticking the landing, Cassidy, Ivanishin, and Vagner went to a recovery staging site at Karaganda, northeast of Dzhezkazgan. The crewmates then part ways as Cassidy returns to Houston through a NASA plane while Ivanishin and Vagner will return to Star City in Russia with a Gagarin Cosmonaut Training Center aircraft.

Together, the three spacemen logged 196 days in space aboard the ISS. It corresponded to accomplishing 3,136 orbits around the Earth, going a total of 83 million miles. 

For Cassidy, it marked his third completed trip to the ISS, for a career total of 378 days in space - the fifth most days for American astronauts. His first mission was as a Mission Specialist on the STS-127 mission, which was tasked to deliver the last components of the Japanese Experiment Module to the space station.

For Ivanishin, the veteran cosmonaut, it was also his third ISS mission, logging a total of 476 days in space. He started as the backup commander for the ISS Expedition 26/27. Expedition 63 was Vagner's first mission to the ISS.

Expedition 63 and the Air Leak

During their stay, the crew worked on various studies conducted at the space station's microgravity environment. Also, they welcomed the pair of Doug Hurley and Bob Behnken - the SpaceX Crew Dragon Demo-2 members - on May 31, 2020.

Among the notable activities conducted by the trio of Cassidy, Ivanishin, and Vagner is the hunt for the abnormal air leak since August, later narrowing down the location of the small leak to the Russian Zvezda service module, which houses scientific equipment.

The persisting air leak was solved with an ingenious solution courtesy of Ivanishin: tea leaves. The veteran cosmonaut released a few leaves from a tea bag in the Zvezda module transfer chamber. They then isolated the chamber by shutting off its hatches and monitoring the leaves, via surveillance cameras, and watched it drift toward a scratch in the wall.

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Check out more news and information on the International Space Station in Science Times.