One of the things I absolutely love about being a space nerd that works where I do is that every time I turn around there's a tiny bit of history staring me in the face. This tends to have the unfortunate side effect of plunging me down the Wikipedia rabbit hole as I chase a juicy tidbit. Not only does this feed my geek, it serves to remind me that, despite 50 years of space travel, it is far from routine. Years of training cannot prepare astronauts and ground personnel for every situation, so improvisation and ingenuity abound. Yet very few of these occasions have entered the public consciousness. I'd like to change that. After all, we do these things because they are hard!
Around the corner from my office, this picture hangs on the wall. At first glance, it's one more shot of spacewalking astronauts doing their job in the shuttle payload bay. Except there are three of them, and I know spacewalks in the shuttle era are normally conducted in pairs. So what mission was this? What was going on? I had to go all the way back to the maiden flight of Endeavour to find out.
Endeavour rocketed into space for the first time on May 7, 1992. The mission was straightforward: a quick pit stop to rescue a communications satellite that had been stranded in a useless orbit by a launch failure, then a couple of days' worth of spacewalks to experiment with construction techniques for what would eventually grace our skies as the International Space Station.
On May 10, Endeavour rendezvoused with the INTELSAT VI satellite. Mission Specialist Pierre Thuot rode to the satellite aboard the Canadarm (RMS in the lingo) to attach an adapter bar that would allow the RMS to handle the satellite and bring it into the payload bay, where Rick Hieb waited. There Thuot and Hieb would attach the rocket motor that would send the satellite on its merry way. However, when Thuot tried to grab the satellite, it began to move away from him. Further attempts to capture it turned this movement into a severe wobble that made it too dangerous for the astronauts to continue.
The next day, after ground controllers stopped the satellite's motion, they tried again with the same amount of success. The engineer who had designed the adapter blamed the satellite manufacturer for not providing NASA with correct data on the satellite. Thuot himself later described INTELSAT VI as "much more dynamic than our training had led us to believe."
The defeated astronauts returned to the shuttle cabin, where they joined their crewmates in pondering the situation. Finally, working with Mission Control, they hit upon a possible solution: by placing Thuot on the arm, Hieb on the starboard rim of the payload bay and a THIRD spacewalker, Tom Akers, on a platform fashioned from the space station assembly experiment, they could grab the errant satellite by hand and guide it into the payload bay.
Given a go after a team of astronauts had rehearsed this procedure on the ground in Houston, Thuot, Hieb, and Akers exited the airlock on what was coincidentally the 100th spacewalk in world history. Shuttle commander Dan Brandenstein guided Endeavour within feet of the free flying satellite. Finally, after 15 minutes of watching the satellite slowly spin in front of them to time their grab, the three astronauts snagged the satellite and brought it in. 8 hours and 29 minutes after the spacewalk had started, the astronauts returned to the shuttle cabin having attached the rocket motor and completing their mission. The duration of this EVA set a record unmatched until 2001.
Endeavour flies a final time next week to deliver supplies and a potentially history making science experiment to the space station whose early development work gave the crew of her maiden voyage the tools they needed to complete their mission. It's good to see history come full orbit!
Sources:
http://en.wikipedia.org/wiki/STS_49 A good jumping off point.
http://science.ksc.nasa.gov/shuttle/missions/sts-49/sts-49-press-kit.txt What was supposed to happen.
http://articles.latimes.com/1992-05-13/news/mn-1687_1_rescue-attempt Thank you for having a free archive, LA Times.
http://uu.cx/flight/49/ Excellent detailed article about the mission.
http://spaceflight.nasa.gov/spacenews/factsheets/pdfs/EVACron.pdf Walking to Olympus. Chronology of Human EVAs.
http://www.archive.org/details/postflight_press_conference_sts-49 The postflight video briefing. Can the crew get any drier describing their mission?
Edit 4-21-11: My mistake. My poor fried brain had the wrong picture. It has been corrected.
Edit 4-21-11: My mistake. My poor fried brain had the wrong picture. It has been corrected.
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