Comments by "H. de Jong" (@h.dejong2531) on "" video.

All of the evidence says Earth is a sphere. The only people who conclude it must be flat, use non-scientific arguments while ignoring the evidence.
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@JohnParker1967 False. The suit had an inner airtight layer, and immediately outside of that, a layer of non-stretchy woven material that stopped the inner layer from expanding.
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Ah, the old argument from incredulity. Instead of researching, you just assume based on no evidence.
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Look at the sky tonight. You can see satellites pass overhead. With simple tools, you can measure their speed and altitude https://www.youtube.com/watch?v=_zApGNHOi0s You'll find an altitude of more than 200 km and a speed of 8 km/s. Every day, you benefit from data generated in space, proving space is real and Earth is not flat.
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@dariousmoiras2476 No. When you measure the speed and altitude of a visible satellite, you'll find an altitude of more than 200 km (4 times higher than any balloon) and a speed of 8 km/s (100 times higher than any balloon can reach). A satellite orbits Earth in 90 minutes to 24 hours, a balloon takes several weeks. High-altitude balloons have a severely limited life: they fail after no more than 4 weeks. So you'd have to keep launching balloons to replace the failures.
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The helmet had a flange that was locked inside a ring. The pressure inside the suit pushes the helmet against a seal. This means the helmet can be closed easily when the suit isn't pressurized, while providing a good seal. https://www.youtube.com/watch?v=htrwFqO8BKM
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@subramaniamchandrasekar1397 You're confusing two things. 1. working with a vacuum on Earth. You have a container at low pressure inside our atmosphere at 1 bar. The pressure inside is lower than outside. The container has to withstand a compression load. 2. a space suit, which is a pressure vessel inside a vacuum, i.e. the pressure inside is higher than outside. The space suit is in tension: it tries to expand. Most materials are much stronger in tension than in compression. A soda can, for example, can hold a pressure of 5 bar. But if you draw a vacuum in that same soda can, it will buckle.
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@subramaniamchandrasekar1397 You continue to confuse things. The Apollo space suit was pressurized to 0.25 bar, in an environment at 0 bar. For tests on Earth, the space suit would be pressurized to 0.25 bar above ambient pressure. The air in the suit was 100% oxygen.
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@subramaniamchandrasekar1397 The tests at 1.25 bar were short enough not to cause health problems. In flight, the CM and LM all had 100% oxygen atmospheres, at pressure of about 0.25 bar, which does not pose a health risk. During launch preparations, the Apollo capsule contains normal air. After launch, vents allow the air to escape, and the environmental control system starts to supply oxygen.
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@subramaniamchandrasekar1397 Your numbers for oxygen toxicity are off. The Lorrain-Smith-effect may occur at a partial oxygen pressure above 0.5 bar for more than about 24 hours. It is a lung toxicity. The Paul-Bert-effect may occur at a partial pressure above 1.6 bar for minutes to a few hours. It is a central nervous system toxicity. The time to onset of symptoms is highly variable but most individuals can tolerate 12-16 hours of oxygen at 1.0 ATA, 8-14 hours at 1.5 ATA, and 3-6 hours at 2.0 ATA before developing mild symptoms. or the Apollo astronauts the time when breathing pure oxygen at a pressure above 0.5 bar was limited to a few hours (2:10 for Apollo 11). Divers routinely prebreathe pure oxygen for several hours before a dive.
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@subramaniamchandrasekar1397 SP-368 Biomedical Results of Apollo: a comprehensive validation program was instituted by NASA in cooperation with the National Academy of Sciences Working Group on Gaseous Environments. Both industrial and Department of Defense laboratories were used in the program. Data obtained from these studies indicated that exposure of man for 14 days to the 100 percent oxygen, 34 500 N/m2 (5 psia) atmosphere selected for the Gemini spacecraft would not impose any physiological problem (Morgan et al., 1965; Welch et al., 1965; Helvey et al., 1965; Mammen et al., 1965) NASA does not employ morons, so they tested this before deciding what atmosphere to use for the Apollo spacecraft and space suits.
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@subramaniamchandrasekar1397 Most experiments with divers are carried out at much higher pressures than 1 bar. That's where things get dangerous.
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@subramaniamchandrasekar1397 The "did they see stars" point is ridiculous. The confusion stems from the fact that the answer is different for each part of the mission, and they were not given enough time to explain fully.
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@subramaniamchandrasekar1397 The space station weighs 400 tons. It would take far more fuel than we can currently launch to get it into a high orbit.
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@subramaniamchandrasekar1397 You claim NASA is lying but you provide no evidence. No space denier ever does: all you have is half-baked arguments that fall apart when examined closely.
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@subramaniamchandrasekar1397 NASA's tests on high-oxygen environments have been corroborated by scientists outside NASA. You just think your half-baked understanding qualifies you to call them liars, when it doesn't.
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@subramaniamchandrasekar1397 I have examined the lunar landings thoroughly, and found no issues. The arguments of the deniers, on the other hand, always fall apart when you examine them. I'm fine with asking questions. That's not what you're doing though; you start from the assumption that the moon landings must be faked and you cherrypick data to fit your narrative. The oxygen issue is an example. Studies show that oxygen toxicity becomes a problem after about a day of exposure to oxygen at 100% and 1 bar. You claim these effects start much sooner than that, but offer no data for your claims.
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@subramaniamchandrasekar1397 Armstrong told the audience that he landed on the moon.
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@subramaniamchandrasekar1397 Yes, they died in a fire, not from oxygen toxicity.
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Here's Neil Armstrong practicing in the SPF vacuum chamber: https://www.youtube.com/watch?v=CDN0S4eJWYY In addition to spacesuit tests, they ran tests where the entire CSM with crew was put into a vacuum chamber for up to 14 days: https://www.youtube.com/watch?v=nEv3dvKvc0I
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@subramaniamchandrasekar1397 The difference between the best vacuum we can achieve on Earth and the vacuum of deep space is 0.00001 Pa. So if we want to test an Apollo space suit, we set the pressure inside the suit to 25000.00001 Pa instead of 25k, and the forces working on the suit will be identical to what it will encounter on the moon.
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@subramaniamchandrasekar1397 No, testing the LM engines on Earth would not result in them achieving 1/6 the height. The LM weighs 15600 kg. The descent engine thrust is max. 4600 kgf, so it wouldn't get off the ground on Earth. The LM was designed to function in the 1/6 G gravity of the Moon, where the LM weighs 2600 kg (15600/6) and its engine has a T/W ratio of more than 1.
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@subramaniamchandrasekar1397 I just looked up the lowest pressures achieved on Earth. The category of 'ultra-high vacuum' starts at 10E-7 Pa. The 'pressure' on the moon is 1 atom per cm3, which is about 10E-12 Pa, or 100,000 times lower. The difference in the force exerted on a spacesuit depends only on the difference in pressure. 10E-7 minus 10E-12 is 0.000 000 099 999. Again, this is a rounding error.
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@subramaniamchandrasekar1397 And? The construction of a vacuum chamber is irrelevant to this discussion.
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@subramaniamchandrasekar1397 The LM was tested, just not on Earth's surface. Apollo 9 tested the LM in Earth orbit. Apollo 10 tested the LM in lunar orbit. They got to within a few hundred meters of the surface, testing almost the entire descent and ascent profile, plus the inflight abort option.
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@subramaniamchandrasekar1397 I'm saying you don't need to achieve a perfect vacuum to test a spacesuit. In fact, you can test a space suit without using a vacuum chamber at all. Pumping up the pressure inside the suit until it is 0.25 bar higher than outside the suit will put exactly the same forces on the suit that it will encounter in space. It's the difference between inside and outside that's important.
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@braininavatnow9197 That's provably nonsense. Construction videos show what the spacecraft were made of: aluminium for structural parts, phenolic resin for the CM heat shield, multilayer insulation for head shielding on the LM. The space suit consists of about 16 different layers, each with different materials.
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