Questions tagged [apollo-program]
NASA's Apollo program was a 17-mission program that focused on landing a human on the lunar surface. The program was the third human spaceflight by NASA, after Mercury and Gemini.
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Why did the flag on the moon stop moving?
In a well intended video debunking the denial of the lunar landing a YouTuber claimed it was the thin lunar atmosphere that brought the flag to a stop. I didn't think that was likely considering how ...
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Did the Apollo Command Module launch with the docking probe already in place?
This question is spun off from a different question I posted, where I was told I should not combine questions into one.
I am interested to learn more about the Apollo Docking System, and particularly ...
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Do the Apollo probe/drogues also serve as an airtight seal when not docked, or is there a separate seal?
I am interested to learn more about the Apollo Docking System. I know that the CM has a Probe that docks to the LM's Drogue. After these two components meet, twelve latches form a solid connection ...
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Where were the Apollo Probe/Drogue stored after docking?
This question is spun off from a different question I posted, where I was told I should not combine questions into one.
I am interested to learn more about the Apollo Docking System. I know that the ...
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How fine was RCS thrust control on the Apollo SM?
I've wondered about how the Apollo spacecraft could rotate to a specified roll angle (for example) and remain there. I know there were two dead bands available, 5 degrees and a much smaller value that ...
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How would an Apollo LM crew have determined which abort mode to use when attempting to land?
I have read a great deal about procedures for Apollo missions, and read much of the online Apollo Flight Journal and Apollo Surface Journal transcripts. When discussing the decision to abort a landing,...
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Can anyone share or provide a source for these 1970s Project Apollo documents
doc title: Manually-aided on-board Apollo cislunar navigation
Document ID: 19710029813
Publisher: INST. OF NAVIGATION,
pub date: January 1, 1970
NTRS Distribution Limits Public
Link to NTRS "...
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Did the Moon really "ring like a bell" when "Apollo 12 punted its ascent stage" into it? If "no one knows why" exactly, what are the primary theories?
The YouTube transcript from The Vintage Space video Crashing Apollo Spacecraft for Science after about 00:29 includes the following. It refers to the seismometer instrument as part of the ALSEP ...
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Where to find practice photos from Apollo training (ALSCC in particular)
We have lots of photos of the Apollo astronauts during their training sessions, and multiple sources mention practice photography, particularly panoramas (see Did Apollo-11 astronauts rehearse their ...
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How was the first continuous communication with LEO spacecraft established?
In the Apollo era, spacecraft had only intermittent contact with mission control as their communication link was “handed off” from the US to South Africa to Australia during the spacecraft’s LEO ...
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What do the Apollo crew mean by "you're five square"
If you watch the Apollo 15 splashdown footage,
you would notice (with CC on) that after the recovery team says "Apollo 15, Apollo 15 this is recovery" one of the astronauts replies "Rog,...
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How many minutes the Apollo astronauts had to wait from splashdown until the first frogmen touched the CM?
The distance between the target point to the splashdown were remarkable small, 3 nautical miles or less. The distance to the recovery ships were small too.
How many minutes the crews had to wait from ...
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how did the Apollo 11 know its precise gyroscopic position?
During lift - off (as per my knowledge) the Apollo 11 had accelerometers that would determine the position of the rocket. This would work great due to the earth's gravity. But how did the Command ...
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Looking for information on this Apollo era CGI animation
In the NASA documentary The Computer and Manned Space Flight, early CGI animations of lunar landing, rendezvous, earthrise etc. are shown. The narration says that these simulations were made prior to ...
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Differences between systems engineering in the days of the Apollo program and in SpaceX [closed]
How was the approach to design different in the days of the Apollo program and today at SpaceX? I know that these are two different things that are difficult to compare. In any case, in both cases ...
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What proportion of the total fuel load in a Saturn V was used to drive the pumps?
In a liquid propellant rocket, power is needed to pump propellant against the pressure inside the combustion chamber. The Rocketdyne F-1 reportedly used 55,000 HP to drive the pumps.
What proportion ...
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Apollo Third Stage SLA Separation design change?
Did NASA change the design of the SLA on the Apollo third stage? First leaving it connected and then having the panels separate from the third stage?
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How long can inertial only navigation systems maintain landing accuracy in LEO?
Inspired by this question, pre GPS all space craft used inertial navigation with periodic fixes from the ground. Inertial systems will drift with time, so the longer between last fix and landing the ...
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Could Apollo have survived the lander toppling over?
Did the Apollo mission have a contingency plan for the lander tipping over? For instance, would it have been possible for the two astronauts to somehow right it?
EDIT
This question is closely related ...
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What spares were taken on Apollo missions, and what was left behind? The question of gloves
In the graphic novel based on John Michael Greer's 'The Next 10 Billion Years', there's a haunting picture of the descent stage of a lunar module (the shorter online version, 'Grounded', is here: ...
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Changes to Apollo that enabled heavier missions
This question has a table that shows the dry weight of the LM grew by 1600 kg between Apollo 11 and 17.
What enabled this weight growth? I know some of it was enabled by improving descent engine ...
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How are parachutes attached to capsule spacecraft?
Spacecraft capsules (Apollo, Orion, Dragon, Starliner, Soyuz, etc) use an arrangement of pilot, drogue, and main parachutes to land. I'm looking for details regarding how and where these parachutes (...
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Why do the boot prints on the moon appear bright in some photographs or film?
I've seen that in some videos or photos of the moon mission, the boot prints appear brighter relative to the untouched ground:
But in some other cases, they are the same brightness as the ground:
Is ...
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Mass Breakdown of Apollo CSM by Subsystems? (also Cost Breakdown)
I am looking for a mass breakdown of the Apollo Command and Service Module by subsystems, like this Lunar Module's chart from the NASA publication After LM. I am particularly interested in how much of ...
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Looking for Apollo Flight Control Hardware Blueprints (such as RHC, THC and COAS)
I've been looking to build replicas of Apollo flight control hardware such as RHC, THC, ACA, TTCA and COAS, and am looking for detailed engineering drawings that show dimensions and internal ...
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