A Russian spacecraft pushed the International Space Station out of position on Friday morning, prompting astronauts to go into emergency mode. It’s the second time Russian hardware has caused such an incident since July.
Cosmonaut Oleg Novitsky was conducting engine tests on the Soyuz spaceship, which is docked to the ISS, on Friday morning when its thrusters fired too aggressively. That moved the station out of its normal orientation, The New York Times reported.
The precise cause is not yet clear, but NASA mission control in Houston told its astronauts that the station had lost control of its orientation and instructed them to follow emergency procedures.
Russia’s space agency, Roscosmos, later said in a statement that the ISS orientation was “temporarily changed” but “swiftly recovered,” and that nobody on board was in danger.
Neither agency has revealed how much the space station moved, or for how long.
“As you can well imagine, when things start going off the rails like that, there’s enough noise on the radar that the clarity of what actually happened is a bit of a mystery,” NASA flight director Timothy Creamer told US astronauts after the Soyuz engines stopped firing, according to the Times.
“We think – and we haven’t got confirmation – we think the thrusters stopped firing because they reached their prop limit,” Creamer said, according to the Times (“prop” usually refers to propellant). “Moscow is checking into it and doing their data analysis.”
In addition to astronauts and cosmonauts living on the orbiting laboratory, a Russian actress and director are currently onboard filming a movie. They launched on October 5 and are scheduled to return to Earth on Sunday, using the spaceship that caused the incident.
NASA mission control mentioned that the incident delayed a film shoot in the space station’s cupola window, according to the Times. It’s unclear if this incident will affect the Russian film crew’s schedule for returning to Earth or the spaceship’s ability to make the trip.
This is the second time this year that a Russian spacecraft has pushed the ISS out of position. Roscosmos launched a new module, called Nauka, to the ISS in July. Shortly after it docked to the station, Nauka began unexpectedly firing its thrusters, trying to pull itself away from the football-field-sized station. A tug of war ensued between the errant module and the four gyroscopes that typically keep the ISS steady.
Nauka’s thrusters wound up spinning the ISS around 540 degrees and flipping it upside down before flight controllers regained control an hour later.
The crew was never in danger during that incident, according to NASA. They didn’t even feel the station move or shake.
That said, Zebulon Scoville, who was in charge of NASA mission control that day, told the Times that it was the first time he’d had to declare a “spacecraft emergency” in his seven years as a flight director.
NASA defines such an emergency as “an anomalous state” that would result in the loss of the entire space station if it were to continue.
“We knew we had a limited amount of time,” Scoville said.