NASA Astronaut Nick Hague and
Russian cosmonaut Alexey Ovchinin are in what NASA director
Jim Bridenstine described as "good condition" after surviving an emergency landing after a booster failure on a Russian
Soyuz rocket Thursday.
"I'm grateful that everyone is safe," Bridenstine said on Twitter.
NASA and Roscosmos, the Russian space agency, pledged a thorough investigation after the aborted launch of a Russian Soyuz rocket. But the incident highlights recent tensions that have surfaced in a long-running collaboration in space between the US and Russia.
The rocket was transporting Hague and Ovchinin from the Baikonur Cosmodrome in Kazakhstan for a six-month stay on the International Space Station. NASA currently depends on Russian Soyuz launch systems to ferry crew members to the station.
Collaboration between the US and Russian space agencies has largely steered clear of geopolitical controversies, despite a standoff between Washington and Moscow that has continued since Russia's annexation of the Black Sea peninsula of Crimea from Ukraine in 2014 and allegations of Russian meddling in the 2016 US presidential election.
In August, however, the detection of a minute pressure leak on the International Space Station became the subject of intense media speculation in Russia. The leak was quickly repaired, but Roscosmos chief Dmitry Rogozin suggested that the leak was caused by something other than an accident or production defect.
Speaking with reporters in Moscow before Thursday's launch, Bridenstine said that Russian-American cooperation in space remained strong, amid an investigation into the cause of the leak.
"That relationship is strong, and whatever happens terrestrially, we've always been able to keep space exploration and discovery and science separate from whatever terrestrial disputes there may be," he said. "What we've got to do is we've got to very dispassionately allow the investigation to go forward without speculation, without rumor, without innuendo, without conspiracy."
NASA and Roscosmos said search-and-rescue teams responded quickly to retrieve the crew members, whose spacecraft parachuted to Earth in an emergency landing in Kazakhstan.
Dramatic footage showed the capsule carrying the crew thumping down in a plume of dust, minutes after it launched.
The rocket had lifted off at 4:40 a.m. ET on a journey that was expected to involve four orbits of the Earth and take six hours.
NASA earlier tweeted that there had been an issue with the booster and that its teams were heading towards the expected touchdown location.
"Teams have been in contact with the crew. Teams are working with our Russian partners to obtain more information about the issue with the booster from today's launch," the US agency said.
"The crew is returning to Earth in a ballistic descent mode. Teams are working to obtain additional information from our Russian partners. Search and rescue teams are in the air and heading towards the expected touchdown location for the Soyuz spacecraft returning to Earth carrying two crew members."
The ballistic descent is a sharper angle of landing compared to normal, NASA said.
By early Thursday afternoon, Ovchinin and Hague were on helicopters, making their way back to Baikonur, NASA said. The agency said the rescue crews were preparing to return them to Moscow, and Roscosmos released still images of the two crew members receiving medical evaluation in Kazakhstan.
NASA later tweeted images of the two men embracing their families back in Baikonur.
Kremlin spokesman Dmitry Peskov said he expected Russian President Vladimir Putin would be briefed on the incident.
Hague, who only joined NASA's astronaut corps in 2013, was on his first space mission.
He and Ovchin in were due to join Expedition 57 Commander Alexander Gerst of the European Space Agency, NASA Flight Engineer Serena Auñón-Chancellor and Roscosmos Flight Engineer Sergey Prokopyev on the ISS. They arrived at the station in June.
Gerst tweeted his relief that the two astronauts were safe, saying the day's events "showed again what an amazing vehicle the Soyuz is, to be able to save the crew from such a failure."
He added: "Spaceflight is hard! And we must keep trying for the benefit of humankind."
The Expedition 57 crew members are working on hundreds of experiments in biology, biotechnology, physical science and Earth science, according to NASA.