Commander Alexander Gerst was ready to welcome two new astronauts to the International Space Station (ISS) — but ended up looking on helplessly as a catastrophic rocket failure sent the incoming crew falling back to Earth.
- The current astronauts on the ISS may need to extend their six-month mission
- It is unknown whether Russia will be able to send replacements to ISS in time
- NASA is looking at the potential of running the ISS without a crew
In a series of photos, Mr Gerst captured the moment a Russian Soyuz rocket malfunctioned at the start of what should have been a routine six-hour flight to deliver two astronauts to the ISS.
The failure of the booster rocket, just two minutes after the launch and at an altitude of 50 kilometres, activated an emergency rescue system which sent the capsule carrying US astronaut Nick Hague and Russian cosmonaut Alexei Ovchinin into a dangerous ballistic descent.
Footage showed the pair shaking around in the capsule, enduring gravitational forces of six to seven times more than is felt on Earth as they came down at a sharper-than-normal angle.
About 30 minutes later the capsule parachuted onto a barren area of steppe in Kazakhstan.
"Glad our friends are fine," Mr Gerst, a European Space Agency astronaut from Germany, tweeted from orbit.
"Spaceflight is hard. And we must keep trying for the benefit of humankind."
Future space station crewing arrangements now in doubt
Russia's rockets are currently the only way to get astronauts to the space station, but all manned flights have been out on hold in the wake of Thursday's accident.
Russian news reports indicated that one of the rocket's four first-stage engines might have failed to jettison in sync with others, resulting in the second stage's shutdown.
For the crew in the capsule, events would have happened very quickly, NASA's deputy chief astronaut Reid Wiseman told reporters at Johnson Space Centre in Houston.
An emergency light would have come on and, an instant later, the abort motors fired, pulling the capsule away from the stricken rocket.
Mr Wiseman said the only thing that went through his mind was "I hope they get down safe."
There was no immediate word on whether Mr Gertz and the current space station crew might need to extend their own six-month missions.
Two spacewalks planned for later this month have been postponed indefinitely, as Mr Hague was supposed to be one of the spacewalkers.
NASA said it was dusting off plans which would allow it to operate the space station without a crew.
Kenny Todd, a space station manager, said the space station's current crew could only stay on board until January — just a month beyond their expected mid-December return.
But he said a replacement space station crew would need to be in place before SpaceX or Boeing demo launches next year.
Russia launches criminal investigation into cause
While the two men landed safely, the aborted mission dealt another blow to the troubled Russian space program.
It also was the first such accident for Russia's manned program in over three decades.
As a result, Russia has launched a criminal investigation into the rocket failure.
Deputy Prime Minister Yuri Borisov said Russia would fully share all relevant information with the US, which pays up to $82 million per ride to the space station.
"I hope that the American side will treat it with understanding," he said.
Relations between Moscow and Washington have sunk to post-Cold War lows over conflicts in Ukraine and Syria, and allegations of Russian meddling in the 2016 US presidential vote, but they have kept cooperating in space.