Trebuchet
Penultimate Amazing
Yup. Happens pretty much weekly. Probably back Saturday.
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Apollo 11 Moon Landing Revisited: Hoax ~vs~ Debunk
- Thread starter Vixen
- Start date
Disbelief
Illuminator
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Shockingly, I would qualify based on these scores. Of course, Mensa would frown on me for slogging through this thread over the past couple of weeks and reaching the end.
Reformed Offlian
Illuminator
You're adorable.
Reformed Offlian
Illuminator
Sure, for example: there are people who hold a view that the earth is flat. And a mature understanding of that view is that it's nonsense.
Just because your view is different doesn't mean that it's any good, or deserving of respect.
Foster Zygote
Dental Floss Tycoon
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I recently came across this drawing showing the configurations for the major proposals for the lunar landing, including the early LOR concept and the final Grumman design as flown.
I can't image what the Gemini Direct flight would have been like. Borman and Lovell said Gemini VII with its nearly 14 day duration was about the limit of human endurance in such a small craft.
I can't image what the Gemini Direct flight would have been like. Borman and Lovell said Gemini VII with its nearly 14 day duration was about the limit of human endurance in such a small craft.
catsmate
No longer the 1
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I would assume some of the designs were from before the decision to use Lunar Orbit Rendezvous, rather than the other options of Earth Orbit Rendezvous (which was proposed to use Gemini components) or direct flight.
grmcdorman
Graduate Poster
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That's correct. In the image, concepts labelled Direct Ascent are those. I'm not sure if there was also a direct from Earth (i.e. neither EOR nor LOR) considered at that stage.
It's worth noting two things: the image shows just how high (and big) Direct Ascent vehicles are, and that Musk's lander - Starship - is a direct-ascent vehicle, and hence essentially similar to those early concepts.
Moved posts talking about other threads and the like to AAH. Keep to the topic of this thread and don't bring in stuff from other threads.
Replying to this modbox in thread will be off topic Posted By: Darat
JayUtah
Penultimate Amazing
An old friend sent me that illustration last week. I told him that without a hatchback model, they wouldn't do very well in the European market.
Yes, the items on the top row are the direct-ascent concepts. It's not a strict pedigree. During the concept and bidding phases, different companies came up with different strategies in formal response to a request for proposals. You're seeing different competing designs. At this time rendezvous and docking were seen as extremely risky, having not yet been attempted. So the mission profile was to go straight from liftoff to the Moon, land an entire ship on the Moon, and then take off from the Moon in either the entire ship or in a ascent portion, leaving the descent stage on the Moon (as Apollo eventually did). Most of the concepts featured an Earth-entry capsule that was the minimal portion of the vehicle for that task: something else that Apollo did.
The operative RFPs were issued before Kennedy's challenge. These were original Eisenhower-era proposals for a calm, sedate Project Apollo. But it was the technical advancement of these proposals that enabled LBJ to convince Kennedy that his Cold War technology demonstrator could reasonably be a crewed Moon landing.
All the competitors settled on a three-module design: entry, mission, and service. The Soyuz spacecraft still uses this concept. The crew spends most of their time in the mission module. They jettison everything except the entry module for final Earth landing. And all the competitors chose some version of a lifting body. The Martin M-410 actually had steering fins just like SpaceX Starship.
The Convair M-1 used a half-cone lifting body entry vehicle, similar to the one Steve Austin crashes in the title sequence of The Six Million Dollar Man. North American's design won because they listened to Max Faget. At NASA, Faget's team had already worked out the aerodynamics and thermodynamics and decided that a blunt body entry vehicle was overall best. NAA proposed a blunt-body truncated cone that we know today as the Apollo command module. Faget eagerly endorsed it. And that's the Orion concept, and to a lesser extent the Crew Dragon concept. Conventional wisdom is that Faget got it right the first time.
The big problem with the direct-ascent profile was all the propellant and thrust it would take to move propellant. The propellant load to return to Earth would have to be soft-landed on the Moon and then lifted off again. The extra propellant to do that (as opposed to just landing people on the Moon) in turn requires a lot of thrust and propellant at Earth liftoff. The Saturn V couldn't lift that much.
The last two items on the top row indicate the kind of incremental thinking that was happening. The NAA CSM design has a single module that served as the lunar landing and liftoff stage. The last item on that row refines the design by separating the lunar descent stage from the lunar ascent stage. The ascent therefore leaves behind all the heavy structure and tanking that was needed to soft-land. And this is what happened in the final design of the lunar module.
And since they all had to be initially part of a rocket, they all suffered from the problem of needing to be a narrow cylinder. This placed the crew compartments atop a sizable propulsion stack and therefore many meters above the lunar surface. The Starship lunar lander will face this problem. The Blue Origin lander places the crew compartment at the bottom and the propulsion module on top.
Switching to lunar orbit rendezvous means you get to leave your return propellant in lunar orbit and greatly reduce the mass you needed to soft-land on the Moon and lift off with. That seriously reduces the overall Earth liftoff mass. But it was a serious gamble because by the time they had frozen that concept as the Apollo mission profile, no one had yet rendezvoused and docked any two spacecraft anywhere. Hence the Apollo and Gemini "direct" concepts on the bottom row continued in development as a backup until there was enough confidence that LOR techniques could be developed. And yes, they would have required two astronauts to spend several days cooped up in a cramped entry vehicle for the whole time.
Yes, the items on the top row are the direct-ascent concepts. It's not a strict pedigree. During the concept and bidding phases, different companies came up with different strategies in formal response to a request for proposals. You're seeing different competing designs. At this time rendezvous and docking were seen as extremely risky, having not yet been attempted. So the mission profile was to go straight from liftoff to the Moon, land an entire ship on the Moon, and then take off from the Moon in either the entire ship or in a ascent portion, leaving the descent stage on the Moon (as Apollo eventually did). Most of the concepts featured an Earth-entry capsule that was the minimal portion of the vehicle for that task: something else that Apollo did.
The operative RFPs were issued before Kennedy's challenge. These were original Eisenhower-era proposals for a calm, sedate Project Apollo. But it was the technical advancement of these proposals that enabled LBJ to convince Kennedy that his Cold War technology demonstrator could reasonably be a crewed Moon landing.
All the competitors settled on a three-module design: entry, mission, and service. The Soyuz spacecraft still uses this concept. The crew spends most of their time in the mission module. They jettison everything except the entry module for final Earth landing. And all the competitors chose some version of a lifting body. The Martin M-410 actually had steering fins just like SpaceX Starship.
The Convair M-1 used a half-cone lifting body entry vehicle, similar to the one Steve Austin crashes in the title sequence of The Six Million Dollar Man. North American's design won because they listened to Max Faget. At NASA, Faget's team had already worked out the aerodynamics and thermodynamics and decided that a blunt body entry vehicle was overall best. NAA proposed a blunt-body truncated cone that we know today as the Apollo command module. Faget eagerly endorsed it. And that's the Orion concept, and to a lesser extent the Crew Dragon concept. Conventional wisdom is that Faget got it right the first time.
The big problem with the direct-ascent profile was all the propellant and thrust it would take to move propellant. The propellant load to return to Earth would have to be soft-landed on the Moon and then lifted off again. The extra propellant to do that (as opposed to just landing people on the Moon) in turn requires a lot of thrust and propellant at Earth liftoff. The Saturn V couldn't lift that much.
The last two items on the top row indicate the kind of incremental thinking that was happening. The NAA CSM design has a single module that served as the lunar landing and liftoff stage. The last item on that row refines the design by separating the lunar descent stage from the lunar ascent stage. The ascent therefore leaves behind all the heavy structure and tanking that was needed to soft-land. And this is what happened in the final design of the lunar module.
And since they all had to be initially part of a rocket, they all suffered from the problem of needing to be a narrow cylinder. This placed the crew compartments atop a sizable propulsion stack and therefore many meters above the lunar surface. The Starship lunar lander will face this problem. The Blue Origin lander places the crew compartment at the bottom and the propulsion module on top.
Switching to lunar orbit rendezvous means you get to leave your return propellant in lunar orbit and greatly reduce the mass you needed to soft-land on the Moon and lift off with. That seriously reduces the overall Earth liftoff mass. But it was a serious gamble because by the time they had frozen that concept as the Apollo mission profile, no one had yet rendezvoused and docked any two spacecraft anywhere. Hence the Apollo and Gemini "direct" concepts on the bottom row continued in development as a backup until there was enough confidence that LOR techniques could be developed. And yes, they would have required two astronauts to spend several days cooped up in a cramped entry vehicle for the whole time.
SpitfireIX
Philosopher
The one where the astronauts have to get winched down to the lunar surface (and, presumably, back up again) looks kind of scary. 
JayUtah
Penultimate Amazing
SpaceX proposes an elevator for the Starship lander.
"In case of fire, use the stairs".
JayUtah
Penultimate Amazing
To be fair, the Apollo lunar module's entrance hatch was effectively one floor up. There was no official contingency plan for the case where an astronaut couldn't negotiate the ladder for whatever reason. The plan for dealing with an astronaut who became unconscious or similarly incapacitated was essentially to administer Last Rites. Consequently an enormous amount of attention was paid to avoiding incapacitation. There's an entire branch of mission planning that contemplates every morbid scenario, but not everything that can possibly arise is considered survivable. That's why space exploration is believed to be dangerous.
That said, astronauts and flight controllers are amazingly ingenious people, the likes of which is very rare today. Had something actually happened, it wouldn't have surprised me in the least if the crew had improvised some solution.
bknight
Master Poster
Technically there is no "dark side", the moon rotates once per lunar orbit as the moon is tidally locked to the earth. We've had images of the far side of the moon for decades, Dscover and more recently the Chinese have imaged a few. But if the Roman is allowed to image the moon we may get more.
JayUtah
Penultimate Amazing
The far side of the Moon is interesting, most notably for its lack of maria. This means it is likely to be geologically (selenologically) interesting in different ways than the near side. Apollo 17 astronaut Jack Schmitt came up with a detailed mission profile for exploring the far side using existing Apollo equipment and procedures. But since Apollo was already being curtailed he didn't have a chance of getting it to happen.
We actually get to see more of the Moon's surface than we think from Earth. While the Moon's rotation rate is quite constant (barring minor librations), its speed along its orbit is not, because the orbit is elliptical. This means sometimes the Moon is moving too fast for its rotation and too slow at other times. This is longitudinal libration. It lets us peek at parts of the eastern and western edges. And the Moon's rotational axis is tilted about 7º from perpendicular to its orbital plane. This means sometimes we get to see up over the top of it, and sometimes we get to see underneath. That's latitudinal libration. All told we can see about 59% of the Moon's surface from Earth, at different times.
We actually get to see more of the Moon's surface than we think from Earth. While the Moon's rotation rate is quite constant (barring minor librations), its speed along its orbit is not, because the orbit is elliptical. This means sometimes the Moon is moving too fast for its rotation and too slow at other times. This is longitudinal libration. It lets us peek at parts of the eastern and western edges. And the Moon's rotational axis is tilted about 7º from perpendicular to its orbital plane. This means sometimes we get to see up over the top of it, and sometimes we get to see underneath. That's latitudinal libration. All told we can see about 59% of the Moon's surface from Earth, at different times.
EHocking
Penultimate Amazing
Disbelief
Illuminator
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I should have said the current end. I have participated in Vixen threads before, so I know the basic framework, so I apologize for my poor word choice.
Metullus
Forum ¾-Wit Pro Tem
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If there is no Dark Side of the Moon, where is NASA going to get all of the electrolysis to make water from oxygen and hydrogen for fueling the ISS in non-geopositioned orbit in the lunar hill country?
bknight
Master Poster
I would think in the polar regions where the sunlight is at a minimum, then inside a crater that never receives sunlight or at least only a brief amount of time.