New record for US astronaut

Whitson's return to Earth on Sunday made her the US space agency NASA's longest flight duration astronaut with 665 days logged during her three missions.

Russian cosmonauts still lead the all-time space endurance list, with Gennady Padalka the record-holder with 878 days in orbit.

The Soyuz capsule - containing Whitson, 57, rookie US astronaut Jack Fischer and veteran Russian cosmonaut Fyodor Yurchikhin – made a parachute touchdown at 7:21 a.m., local Kazakh time.

During her third mission on ISS - extended to nine months after Russia scaled back its deployments - Whitson conducted experiments, including studies of cancerous lung tissue and bone cells.

Whitson and Fischer had also supported research into the physical changes to astronauts' eyes caused by prolonged exposure to micro-gravity, NASA said in its summary of the ISS' 52nd mission.

Spacewalking record

Whitson completed four spacewalks, adding to her previous six outings and setting a record for the most time spacewalking by a woman.

During an in-flight interview last Monday, the biochemist said: "I feel great. I love working up here. It's one of the most gratifying jobs I've ever had."

She admitted to also being keen to prepare fresh food back on Earth, "vegetables that I want to saute, things that I've missed up here.”

In June, Whitson had already eclipsed the previous 199-day single stay record set previously by Italian astronaut Samantha Cristoforetti.

Hurricane complicates return

NASA said Friday it was reviewing Whitson and Fischer' expected return to the Johnson Space Center in Houston, Texas, because of the "impacts” and aftermath of Hurricane Harvey.

Mission Control had, however, remained operational during and following the storm, NASA added.

Fischer and Yurchikhin had been aboard the ISS since June.

Whitson's two previous crewmates, who were launched with her last November, returned to Earth three months ago.

The crew remaining on board the ISS on its 53rd expedition comprises Randy Bresnik of NASA in command, and Sergey Ryazanskiy of Russia's Roscosmos agency and Paolo Nespoli of the European Space Agency.

ipj/sms (Reuters, AFP)