During Chris Hadfield’s first flight, he and his fellow astronauts had to navigate a quarter-million-pound shuttle toward a target the size of a coffee cup saucer on the Russian Mir Space Station.
Hadfield’s job was to relay the speed and range information to the pilot as they were docking. This was super important because the docking was an extremely high-precision event. They had a two-minute window to dock, and they had to be traveling a 10th of a foot per second (plus or minus 3/100ths of a second). Failure to do so would be catastrophic.
“If you hit Mir just a little too soft, then the spring mechanisms would bounce you off,” Hadfield explained. “If you hit Mir just a little too hard, then you would break Mir in half and kill the three people on board. So you’ve got to hit it exactly right.”
Even if you’re doing it on the fly and making it up as you go along, you can make it up in a smart way,” he said.
When the crew was about 30 feet away, the two sensors started telling them different things. “One of them told us we were at 32 feet, and the other one told us we were at 20 feet,” Hadfield said, “They’re either both wrong or one of them is completely wrong. Now, what do you do? There’s nobody to ask. If the crew onboard the flight deck of the shuttle don’t solve this problem in the next 30 seconds, then the whole flight is bust and done.”
Hadfield said he “went back to basics.” He knew the docking module’s dimensions, and he used his thumb to eyeball the distance through a window. This told him that they were about 21 feet away and not 32 feet away. He used his stopwatch to do the math to figure out how fast they were going and when they should fire thrusters. They ended up being spot on, hitting the docking target at the correct speed and well within the time envelope (about 3 seconds early, he told BuzzFeed Science).
“It wasn’t for a few minutes before one of us looked around and said, ‘Hey, we did it! We’re actually here.’ That was a big relief of emotion on board,” Hadfield said.
Bob Curbeam was no stranger to spacewalking when he was installing upgrades to the International Space Station. Still, he wasn’t expecting a cooling line to break and spew toxic ammonia all over his suit.
A spacecraft is a closed system, meaning that the only air you have to work with is the air you brought up with you. That means an astronaut better be damn sure they are not bringing anything toxic back into the air with them. First, Curbeam had to stop the leak. Then he had to figure out how he was going to get back into the space shuttle without bringing in the volatile ammonia contaminating his spacesuit.
Curbeam handled the leak with no problems. “Even though we’re doing things on the fly, we understood the hardware, and the system, and how it works so well," he said. "The training is so good, that even if you’re doing it on the fly and making it up as you go along, you can make it up in a smart way.”
NASA
Then next problem was the contamination. Some good old-fashioned science helped with that one. Ammonia has a low boiling point, so he just needed to vaporize it off of his suit. To do this he simply "baked" himself in sunlight for an extra 30 minutes — arguably one of the most surreal and terrifying sunbathing methods a human can experience.
Later, a fellow astronaut brushed off the suit and equipment. To be doubly sure, they partially vented the shuttle airlock. Next, to be even MORE careful, the shuttle crew all wore oxygen masks inside until they were positive nothing had made its way in.
Nothing did make its way in, and Curbeam added more time to his already impressive cumulative spacewalk time.
Scott Parazynski had to perform some hero-level spacewalking when a jammed solar panel threatened the safety of the entire ISS (International Space Station) crew and the ISS itself. The main mission objective was to install a new module on the ISS that would serve as a node for the addition of future research laboratories. Part of the mission required changing the location of an array of solar panels.
“Things were going along really, really well,” Parazynski told BuzzFeed Science, “until the crew inside commanded these large solar panels to extend.” They got jammed up and the panels began to tear.
“It was unsafe to continue to extend this panel any further; you couldn’t retract it either,” Parazynski said. “There was concern that if we even tried to undock the space shuttle it might rip apart and hit the shuttle, and we could have another space shuttle Columbia disaster on our hands. Or, we could damage the International Space Station and have everyone evacuate.”
After 72 hours of grueling work on the ground, NASA came up with a plan — Parazynski would have to travel further away from the safety of an airlock than had ever been previously attempted. It wasn’t only the distance that was nerve-wrecking. Parazynski explained:
“There was a real danger that we could do even worse damage to the Space Station. Then there was the potential of risk to myself, because if there was any metal to metal connection with the solar panel, or arcing, it could actually electrocute me or cause ignition of the 100% oxygen in my spacesuit.
"All the tools that I was working with had to be specially insulated. The metal parts of my spacesuit had to be wrapped in special tape,” he said. Thankfully, everything worked out, and the mission was a success. “I still to this day think it’s one of NASA’s greatest accomplishments,” Parasynski said.
NASA
Jerry Linenger was in the middle of an extended stay on the Mir space station when a catastrophic fire threatened what was then meant to be the longest period of time of any American astronaut spent in space.
The station normally held three astronauts at a time, Linenger told BuzzFeed Science, unless the crew was in the middle of switching personnel over, when two crews would be in the station at the same time. With six astronauts on board the station the amount of oxygen produced by the regular tanks was sometimes not sufficient, and in those cases the crew needed to open a supplemental tank.
Things went from jovial to terrible in a split second, when the tank of concentrated, combustible, oxygen-based chemicals caught fire and turned into what can only be described as a huge, unstoppable blowtorch. “I was sucking down some dehydrated borscht,” Linenger said, “and next thing you've got the master alarm blaring.”
This was pretty much a worst-case scenario for the astronauts and cosmonauts on Mir. There are three things that you are on your own for — Linenger said, “You better respond more or less automatically to [them] because there's no one that can help you.”
Those things are fire (check), toxic substances in the air (from a super-hot flame burning through equipment), and rapid decompression (which would almost certainly happen if the flame burned a hole through the thin aluminum separating the inside from the vacuum of space).
“Things were going along really, really well,” Parazynski told BuzzFeed Science, “until the crew inside commanded these large solar panels to extend.” They got jammed up and the panels began to tear.
The fire blazed for 14 minutes as Linenger and his crew made sure that secondary fires didn’t catch by dousing things in its path with fire extinguishers. "The flame ate up the chemical, melted the canister, melted insulation — our wires for example — around that area,” Linenger said, “It was a hot, hot, hot fire burning out of control.”
As three astronauts were fighting the blaze, the other three crew members were preparing a Soyuz for an emergency escape. But there was a problem. One of the two Soyuz ships was blocked by the fire, so only three of the six would be able to escape Mir. “That would've been a tough decision,” Linenger said with striking nonchalance. “Who goes and who stays?”
Luckily for the crew, that tough decision never had to be made. “We were able to finally keep it from spreading,” Linenger said, “and then we faced the problem of trying to deal with the smoke and trying to breathe in a contaminated atmosphere.” The team assessed the damage and wore oxygen masks until they were sure the environmental risks were gone.
“You've got to get rid of the distractions, put the fear away, and you sort of realize, ‘If I don't stay calm, I'm dead.’”
“I still to this day think it’s one of NASA’s greatest accomplishments,” Parasynski said.
Soyeon Yi, the first Korean in space, was celebrating a successful and productive visit to the ISS as she boarded a Russian Soyuz spacecraft to return home to Earth. That’s when everything went wrong.
There were some problems with the detachment of the Soyuz, and that put the crew on a less than desirable trajectory. The onboard computers sensed this and switched to a “ballistic reentry,” a backup method that relies solely on atmospheric drag but ensures that the heat shield is still able to protect the inhabitants of rapidly falling spacecraft.
They were coming in steep, fast, and hot, but they were nowhere near on course.
Normally, Soyeon told BuzzFeed Science, you expect there to be two or three recovery helicopters right there when you land and a whole team to help you out of the vehicle. “When we landed,” Soyeon said, there was “nobody around us.”
Everything was a big struggle at that point because the force of gravity is overwhelming when you have spent time in space, and the crew had to “crawl” out of the craft on their own.
"If the crew onboard the flight deck of the shuttle don’t solve this problem in the next 30 seconds, then the whole flight is bust and done."
“Finally,” she said, they were able to get out of the capsule and “lie on the grass.” It was then that some shocked and almost certainly terrified Kazakhstani nomadic herders came across what must have looked like an otherworldly scene.
“They had no idea about the space program, they had no idea about astronaut[s] and they [had] really big, huge eyes,” she said. “They finally realized we [were] humans, not an alien, and they help[ed] us.”
The shepherds helped get one of the crew members who remained in the Soyuz out. The astronauts even asked the nomads if they had a cell phone. (They did not). Eventually, realizing nobody knew where they were, they went back into the Soyuz and used a GPS and satellite phone to make contact with the Russian Space Agency.
Finally, a helicopter arrived on the scene, nearly 300 miles away from their expected location.
Soyeon said that the whole experience was probably a lot more terrifying for everyone wondering where they were than it was for her. She thought of the thousands of Koreans who had no idea what had happened to them, knowing many people were intently watching the first person from their country return from space.
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