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Gemini IX-A Launches Cernan for Perilous First Untethered Spacewalk Attempt

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🚀 60 years ago today, Gemini IX-A launched Cernan and Stafford for a three-day mission riddled with mishaps. Cernan performed America’s 2nd EVA which he called “the spacewalk from hell” as he became the first person to orbit Earth entirely outside a spacecraft. From Gemini Remastered: “Before launch, Deke Slayton, who now ran flight crew operations, entered the room where Stafford was suiting up and asked the suit technician to leave and closed the door. He expressed NASA’s concerns about the EVA and added “In case Cernan dies out there, you’ve got to bring him back, because we just can’t afford to have a dead astronaut floating around in space.” Stafford set out his concerns about how difficult that would be and ultimately, he was Commander and he’d make the call. After suiting up, Cernan quizzed Stafford: “Deke was in there talking to you quite a while. What did he say?” Stafford replied: “He just said he hoped we’d have a good flight.” Launch day came May 17, but the rendezvous-target Agenda took a nosedive into the ocean for its launch. NASA switched to a backup ATDA target vehicle (which failed to deploy properly in orbit, leaving it useless, looking like an “angry alligator”). The Gemini IX crew faced multiple launch scrubs over 17 days, with six separate entries into the spacecraft for launch. Cernan was to test a new AMU backpack with hydrogen peroxide thrusters. 80 Velcro patches were bonded to the exterior of the spacecraft and his gloves to assist in crawling to the AMU, where he was to do an untethered free-floating spacewalk — a bold mission plan that did not succeed until McCandless did it in 1984. Cernan’s suit was made extra fire retardant to resist burn through by the AMU thrusters. But this made it very rigid and difficult to move in space (like a “rusty suit of armor”). Every movement required immense exertion, which caused him to sweat profusely, overwhelming his suit's environmental control system and causing his helmet faceplate to completely fog up. He had to use his nose to wipe a small visibility window in his faceplate as he fumbled from a lack of handholds. His intense thrashing ripped through seven inner layers of heavy thermal insulation on the back of his suit, leaving a triangle of skin unprotected. When the spacecraft rotated into the daytime side of its orbit, the exterior of the suit was hit by raw, unfiltered sunlight at a blistering 250°F. Without the insulation, the searing solar heat baked right through the remaining pressure bladder layer. Cernan recalled feeling a scalding, fiery sensation on his lower back but had to ignore it because he was already fighting for his life while blind from the fogged visor. His heart rate hit 180bpm and the flight surgeon was concerned he could lose consciousness. He also lost communications fidelity, resorting to a binary code: one squawk for yes, two for no. Cmdr. Stafford decided to cancel the AMU jetpack test. Cernan called out to CAPCOM Neil Armstrong in mission control: “You might tell everyone down there I’m sure sorry about this.” Because the pressurized suit had ballooned in size with outstretched limbs larger than the hatch opening, and with Cernan completely exhausted and blind, getting back inside the spacecraft was a brutal physical struggle for both men. Together, they used the mechanical hatch-cranking mechanism to literally compress Cernan’s stiff suit and force the door closed against his helmet causing him to almost black out from an inability to breathe. Overall, Cernan lost 13 lbs. from extreme dehydration. Despite the setbacks, NASA learned valuable lessons about spacesuit design and the need for visible handholds for EVAs (which was corrected for Apollo). Here are some heroic artifacts from the Future Ventures museum: 1) The newest addition to the collection, Cernan’s Constellation Chart and Greek Alphabet Cue Card, as annotated and flown on Gemini IX-A. On the upper border, Cernan refers to the planned rendezvous with the ATDA. The accompanying Gemini 9 constellation chart showed key navigation stars labeled with their Greek letter designations (like α Lyrae, β Orionis). Since astronauts weren’t trained astronomers, they carried a Greek letter cheat sheet to quickly decode those symbols into star names and locations. They would use the legend to match ‘α’ to the brightest star in a constellation, ‘β’ to the next, and so on, letting them correctly identify stars through the spacecraft’s sextant/telescope for celestial navigation. 2) Original left-handed glove from the Gemini G3C space suit made by the David Clark Company. 3) ITT Interphones used by the frogmen during recovery at sea; it was a pluggable hard line (like in the Matrix) used throughout Gemini after splashdown. The frogmen welcome the astronauts home and let them know when it was safe to open the hatch. For Apollo, NASA switched to Motorola radios. 4) Photo of the frogmen welcoming a weary Cernan and Stafford back to Earth, with orange interphones clearly visible.

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Steve Jurvetson@FutureJurvetson·7hOriginal post
🚀 60 years ago today, Gemini IX-A launched Cernan and Stafford for a three-day mission riddled with mishaps. Cernan performed America’s 2nd EVA which he called “the spacewalk from hell” as he became the first person to orbit Earth entirely outside a spacecraft. From Gemini Remastered: “Before launch, Deke Slayton, who now ran flight crew operations, entered the room where Stafford was suiting up and asked the suit technician to leave and closed the door. He expressed NASA’s concerns about the EVA and added “In case Cernan dies out there, you’ve got to bring him back, because we just can’t afford to have a dead astronaut floating around in space.” Stafford set out his concerns about how difficult that would be and ultimately, he was Commander and he’d make the call. After suiting up, Cernan quizzed Stafford: “Deke was in there talking to you quite a while. What did he say?” Stafford replied: “He just said he hoped we’d have a good flight.” Launch day came May 17, but the rendezvous-target Agena took a nosedive into the ocean for its launch. NASA switched to a backup ATDA target vehicle (which failed to deploy properly in orbit, leaving it useless, looking like an “angry alligator”). The Gemini IX crew faced multiple launch scrubs over 17 days, with six separate entries into the spacecraft for launch. Cernan was to test a new AMU backpack with hydrogen peroxide thrusters. 80 Velcro patches were bonded to the exterior of the spacecraft and his gloves to assist in crawling to the AMU, where he was to do an untethered free-floating spacewalk — a bold mission plan that did not succeed until McCandless did it in 1984. Cernan’s suit was made extra fire retardant to resist burn through by the AMU thrusters. But this made it very rigid and difficult to move in space (like a “rusty suit of armor”). Every movement required immense exertion, which caused him to sweat profusely, overwhelming his suit's environmental control system and causing his helmet faceplate to completely fog up. He had to use his nose to wipe a small visibility window in his faceplate as he fumbled from a lack of handholds. His intense thrashing ripped through seven inner layers of heavy thermal insulation on the back of his suit, leaving a triangle of skin unprotected. When the spacecraft rotated into the daytime side of its orbit, the exterior of the suit was hit by raw, unfiltered sunlight at a blistering 250°F. Without the insulation, the searing solar heat baked right through the remaining pressure bladder layer. Cernan recalled feeling a scalding, fiery sensation on his lower back but had to ignore it because he was already fighting for his life while blind from the fogged visor. His heart rate hit 180bpm and the flight surgeon was concerned he could lose consciousness. He also lost communications fidelity, resorting to a binary code: one squawk for yes, two for no. Cmdr. Stafford decided to cancel the AMU jetpack test. Cernan called out to CAPCOM Neil Armstrong in mission control: “You might tell everyone down there I’m sure sorry about this.” Because the pressurized suit had ballooned in size with outstretched limbs larger than the hatch opening, and with Cernan completely exhausted and blind, getting back inside the spacecraft was a brutal physical struggle for both men. Together, they used the mechanical hatch-cranking mechanism to literally compress Cernan’s stiff suit and force the door closed against his helmet causing him to almost black out from an inability to breathe. Overall, Cernan lost 13 lbs. from extreme dehydration. Despite the setbacks, NASA learned valuable lessons about spacesuit design and the need for visible handholds for EVAs (which was corrected for Apollo). Here are some heroic artifacts from the Future Ventures museum: 1) The newest addition to the collection, Cernan’s Constellation Chart and Greek Alphabet Cue Card, as annotated and flown on Gemini IX-A. On the upper border, Cernan refers to the planned rendezvous with the ATDA. The accompanying Gemini 9 constellation chart showed key navigation stars labeled with their Greek letter designations (like α Lyrae, β Orionis). Since astronauts weren’t trained astronomers, they carried a Greek letter cheat sheet to quickly decode those symbols into star names and locations. They would use the legend to match ‘α’ to the brightest star in a constellation, ‘β’ to the next, and so on, letting them correctly identify stars through the spacecraft’s sextant/telescope for celestial navigation. 2) Original left-handed glove from the Gemini G3C space suit made by the David Clark Company. 3) ITT Interphones used by the frogmen during recovery at sea; it was a pluggable hard line (like in the Matrix) used throughout Gemini after splashdown. The frogmen welcome the astronauts home and let them know when it was safe to open the hatch. For Apollo, NASA switched to Motorola radios. 4) Photo of the frogmen welcoming a weary Cernan and Stafford back to Earth, with orange interphones clearly visible.