The International Space Station (ISS), which went out of control last week, may have flipped from its original position by more than 45 degrees, pushing the crew and station into a spaceflight emergency, according to American space agency Nasa. The officials have said that the space station is still recovering from the mishap.
The ISS spiralled out of control briefly last Thursday when jet thrusters on the Russian research module Nauka inadvertently reignited a few hours after it had docked to the space station. The reignition caused the entire orbital outpost to pitch out of its normal flight position some 250 miles above the Earth with seven crew members aboard.
In a detailed interview with The New York Times, the flight director who was the incharge at NASA’s mission control centre divulged that there are some more factual details of the incident.
Zebulon Scoville confirmed what he saw during his shift. The ISS spun one-and-a-half revolutions – about 540 degrees. It then came to a stop but upside down, said Scoville. This was followed by a 180-degree forward flip to get back to its original orientation, he said. This tumbling of the station not only caught everyone’s attention, but also on technical levels messed up the antennas set up for communication in the microgravity.
Scoville, who was originally on his off on Thursday, assured that neither the astronauts nor the station was in danger.
The initial warning signs did not alarm the space officials, who took them for a false alerts, till they looked at the video monitors.
“And so at first I was like, ‘Oh, is this a false indication?’ And then I looked up at the video monitors and saw all the ice and thruster firings. This is no kidding. A real event. So let’s get to it. You get about half a breath of ‘Oh, geez, what now?’ and then you kind of push that down and just work the problem,” Scoville told The New York Times.
Altitude control over the station was lost for 45 minutes, as ground-based flight teams activated thrusters on another module of the outpost and on a separate cargo ship previously docked to the complex to restore its proper alignment, according to Nasa.
During that time, the ISS, which is about the length of an American football field, was slowly pitching end-over-end at a peak rate of about half a degree per second, equivalent to nearly four rotations per hour, Nasa said.
Communication with the crew also was lost twice for several minutes during the emergency.
Russia on Friday said that a likely software glitch, and possible lapse in human attention, were to blame for throwing the ISS out of control. The Russian space officials said that the work was proceeding to activate a newly attached module at the centre of the mishap.
The mishap has now prompted Nasa to postpone the planned launch of Boeing Co’s Starliner space capsule. The highly anticipated un-crewed test flight to the space station was set for Friday from Cape Canaveral, Florida but has been scrubbed off for now.
(With inputs from agencies)
