For 47 minutes, the ISS lost control of its orientation when the firing occurred a few hours after docking.

The station's position is key for getting power from solar panels and or communications. Communications with ground controllers also blipped out twice for a few minutes.

Flight controllers regained control using thrusters on other Russian components at the station to right the ship, and it is now stable and safe, Nasa said.

The seven crew members aboard - two Russian cosmonauts, three Nasa astronauts, a Japanese astronaut and a European space agency astronaut from France - were never in any immediate danger, according to Nasa and the Russian state-owned news agency RIA.

"We haven't noticed any damage," Joel Montalbano, the space station program manager, told a press conference. "There was no immediate danger at any time to the crew."

Mr Montalbano said the crew didn't really feel any movement or any shaking. Nasa said the station moved 45 degrees out of attitude, about one-eighth of a complete circle. The complex was never spinning, Nasa spokesman Bob Jacobs said.

Nasa's human spaceflight chief Kathy Lueders called it "a pretty exciting hour".

Russian space officials downplayed the incident with Dmitry Rogozin, the head of Roscosmos, tweeting: "All in order at the ISS. The crew is resting, which is what I advise you to do as well."

The malfunction prompted Nasa to postpone until at least Aug 3 its planned launch of Boeing's new CST-100 Starliner capsule on a highly anticipated uncrewed test flight to the space station.

The Starliner had been set to blast off atop an Atlas V rocket on Friday from the Kennedy Space Center in Florida. It will be Boeing's second attempt to reach the station before putting astronauts on board after software problems botched the first test.

'Tug of war between the modules'
Thursday's mishap began about three hours after the multipurpose Nauka module had latched on to the space station, as mission controllers in Moscow were performing some post-docking "reconfiguration" procedures, according to Nasa.

The module's jets inexplicably restarted, causing the entire station to pitch out of its normal flight position some 250 miles above the Earth, leading the mission's flight director to declare a "spacecraft emergency", US space agency officials said.

An unexpected drift in the station's orientation was first detected by automated ground sensors, followed 15 minutes later by a "loss of attitude control" that lasted a little over 45 minutes, according to Mr Montalbano.

Flight teams on the ground managed to restore the space station's orientation by activating thrusters on another module of the orbiting platform.

In its broadcast coverage of the incident, RIA cited Nasa specialists at the Johnson Space Center in Houston, Texas, as describing the struggle to regain control of the space station as a "tug of war" between the two modules.

At the height of the incident, the station was pitching out of alignment at the rate of about a half a degree per second, Mr Montalbano said during a Nasa conference call with reporters.

The Nauka engines were ultimately switched off, the space station was stabilized and its orientation was restored to where it had begun, Nasa said.

Communication with the crew was lost for several minutes twice during the disruption, but "there was no immediate danger at any time to the crew," Mr Montalbano said. He said "the crew really didn't feel any movement".

Had the situation become so dangerous as to require evacuation of personnel, the crew could have escaped in a SpaceX crew capsule still parked at the outpost and designed to serve as a "lifeboat" if necessary.

What caused the malfunction of the thrusters on the Nauka module, delivered by the Russian space agency Roscosmos, has yet to be determined.

Repeated delays due to technical issues
Russia's long-delayed 22-ton lab called Nauka had arrived on Thursday, eight days after it launched from the Russian launch facility in Baikonur, Kazakhstan.

The launch of Nauka, which will provide more room for scientific experiments and space for the crew, had been repeatedly delayed because of technical problems. It was initially scheduled to go up in 2007.

In 2013, experts found contamination in its fuel system, resulting in a long and costly replacement. Other Nauka systems also underwent modernisation or repairs.

Stretching 43 feet (13 meters) long, Nauka became the first new compartment for the Russian segment of the outpost since 2010. On Monday, one of the older Russian units, the Pirs spacewalking compartment, undocked from the station to free up room for the new lab.

Nauka will require up to 11 spacewalks beginning in early September to prepare it for operation.