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   sometimes complexity is the enemy of reliability. So in some ways we've   
   gone backwards. We have more powerful computers but less reliable ones. We   
      
      
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    have more features but more bugs. We've traded simplicity for   
   capability. And that's one reason why it's hard to go back to the moon because   
   we can't accept the simplicity of the Apollo approach. We want more capability,   
   more redundancy, more safety features, and all of that adds complexity. Now,   
   let me talk about the space suits. The Apollo A7L space suit was a marvel of   
   engineering. It had to maintain pressure about 3.7 pounds per square inch. It   
   had to provide oxygen. It had to remove   
      
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    carbon dioxide. It   
   had to regulate temperature and it had to be flexible enough to allow the   
   astronauts to move. Think about what's involved here. The pressure inside the   
   suit wants to make it balloon out like an inflated tire. But the astronauts   
   needed to bend their joints, move their fingers, walk around. So the suit   
   had to have special joints, convoluted sections that allowed movement while   
   maintaining pressure. And the cooling system was ingenious. Water cooled   
   garments worn under the suit.   
      
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    Water circulated through tubes,   
   absorbing body heat, then passing through a sublimator that vented the heat   
   into space. Elegant, simple, effective. But here's what's remarkable. They   
   designed these suits in just a few years. They tested them, refined them,   
   and they worked. The astronauts spent hours on the lunar surface in these   
   suits. No failures, no catastrophic leaks, no overheating. Compare that   
   to today. NASA's new space suit program has been in development for over   
   a decade and is billions over budget. The suits   
      
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    still aren't   
   ready. And when they are ready, they'll be more complex, more capable,   
   but also heavier and more expensive than the Apollo suits. Why? Because   
   we've added requirements. We want longer mission duration. We want better   
   mobility. We want more sizes to fit different body types. All good things,   
   but all of them add complexity and cost. The Apollo suits were custommade   
   for each astronaut. They fit perfectly, but they were also specialized for   
   moon missions. They wouldn't work as well for Mars or for   
      
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    long   
   duration space walks. So again, we're trading simplicity for versatility, and   
   that makes it harder and more expensive. Now, let me talk about something that   
   really puzzles people. The lunar module. This thing looked like it was made   
   from tin foil and curtain rods. It didn't look like it could fly in Earth's   
   atmosphere, let alone land on the moon. But appearances are deceiving. The   
   lunar module was actually a brilliant piece of engineering. You see, on the   
   moon, there's no atmosphere, no aerodynamics.   
      
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    So, the spacecraft   
   doesn't need to be streamlined. It just needs to be functional. And the   
   thin walls, that's because every pound matters. Getting mass to the moon is   
   incredibly expensive in terms of fuel. So, they made everything as light as   
   possible. The walls were just thick enough to maintain pressure and provide   
   micromedoride protection, nothing more. And you know what? It worked. The   
   lunar module landed six times. It took off six times. It rendevued with the   
   command module six times. Perfect record. But here's what's   
      
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   interesting. The descent engine, the rocket that lowered the lunar module to   
   the moon's surface, had never been tested in a full landing profile before   
   Apollo 11. They tested it on Earth in vacuum chambers, in simulators, but   
   never in actual lunar conditions. So when Armstrong and Aldrin descended   
   to the moon, they were essentially test pilots. They were trying something   
   that had never been done before and it worked on the first attempt. Now,   
   you might say they were lucky, and maybe they were,   
      
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    but I   
   think it's more than luck. I think it's a testament to the quality of the   
   engineering, the thoroughess of the testing, the skill of the astronauts,   
   but it also shows how much risk they were willing to accept. Today, we   
   would never attempt something like that. We'd want multiple unmanned test   
   landings first. We'd want to prove the system before we put humans on it. And   
   that's another reason why it's hard to go back because our risk tolerance has   
   changed. We're not willing to accept the same   
      
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    level of danger that   
   they accepted in the 1,960 seconds. Now, let me talk about navigation. How do   
   they know where they were? How do they navigate from Earth to the moon with   
   such precision? Well, they use several techniques. First, they had powerful   
   telescopes on Earth tracking the spacecraft. Ground stations could measure the   
   spacecraft's position and velocity by analyzing the radio signals, but they   
   also had onboard navigation. The spacecraft had a sextant. Yes, a sextant like   
   sailors used for centuries   
      
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    adapted for space. The astronauts could   
   sight on stars and use those measurements to calculate their position. And   
   the guidance computer would take all this information, the ground tracking,   
   the seextant measurements, the inertial measurements, and compute the optimal   
   trajectory. It's remarkable when you think about it. They were navigating   
   across a quarter million miles of space with a combination of ancient   
   techniques, the seextant, and cutting edge technology. And it worked. But   
   here's what fascinates me. The   
      
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    accuracy was extraordinary. They   
   could hit a target on the moon within a few miles. That's like throwing   
   a dart from New York and hitting a bullseye in Los Angeles. The precision   
   required is mind-boggling. And they did it with 1,960 seconds technology with   
   limited computational power, with techniques that seem almost primitive by   
   today's standards. Today, we have GPS, we have precise atomic clocks, we have   
   powerful computers. Navigation should be easier and in some ways it is. But in   
   other   
      
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    ways we become dependent on these systems. We've lost the   
   ability to navigate using simpler methods. And that's a problem for deep space   
   missions. GPS only works near Earth. Our atomic clocks need to be synchronized   
   with Earthbased systems. If something goes wrong, if we lose contact with   
   Earth, can we still navigate? The Apollo astronauts could they had backup   
   methods. They could navigate by the stars if necessary. That robustness is   
   something we need to recapture. Now, let me talk about life support. Keeping   
      
      
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    astronauts alive in space is incredibly challenging. You   
   need oxygen. You need to remove carbon dioxide. You need water. You need   
   temperature control. You need waste management. The Apollo spacecraft used   
   chemical systems for most of this. Oxygen was stored in tanks. Carbon dioxide   
   was removed using lithium hydroxide canisters. Water was a byproduct of the   
   fuel cells that generated electricity. It was a consumable system. Use it   
   once and throw it away. Not very efficient, but simple and reliable. Today,   
   the International   
      
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    Space Station uses regenerative systems. It   
   recycles water. It splits water into oxygen and hydrogen. It scrubs and   
   recycles the air. Much more efficient for long duration missions, but also   
   much more complex. More things to break, more maintenance required. For a   
   moon mission, the Apollo approach was perfect. The missions were short, just   
   a week or so. Consumables worked fine. But for Mars, for longer missions, we   
      
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   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)