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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Which company provided communication equipment for Apollo missions in which Neil Armstrong was a part?

In July 1969, the Apollo mission transmitted Neil Armstrong’s first steps on the moon to millions around the world. Which famous company provided the entire communication equipment for the project?
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Calculating Apollo launch azimuth

The launch azimuth for Apollo missions to the general area of the lunar equator was approximately 70 degrees. Could someone explain in simple terms how this figure is arrived at? I presume that if ...
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What went wrong with Apollo 15 astronaut Al Worden's seat when he was all alone, circularizing?

The X article NASA shock: Apollo 15 astronaut's Moon landing confession - 'Can't do anything to me now' says "NASA astronaut Alfred "Al" Worden dropped an astonishing Apollo 15 ...
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Did the Apollo LM's cockpit altitude displays account for the pointing angle of the radar altimeter?

The Apollo LM had a radar altimeter which was particularly critical in the final stages of landing. It could be set to two different pitch angles, either aimed backwards by 24º to be used during the ...
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Are there any close-up photos of the screens used in the MOCR2 from the Apollo era where text features can be distinguished?

The question is mostly about the fonts used in those screens. AFAIK, the images were slides superimposed with data generated by computers that was captured from CRTs by cameras and piped into the MOCR ...
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was Saturn V engine J-2 throttleable?

Were the J-2 engines of the third stage of Saturn V throttable? I know that the F-1 for first was not, but what about J-2? I could not find any information about it. Any reference or info for this? ...
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How exactly was Apollo CSM attitude changed (from a current one to a new required one)?

This answer to a related question suggests that the order in which rotations around three principal axes are applied (in order to estimate the conversion of an attitude to a set of roll, pitch and yaw ...
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Confusion with Apollo CSM attitude maneuvers (roll, pitch and yaw) during coasting to/from the Moon

Some time after Transposition, Docking, and Extraction maneuver (when coasting to the Moon) or after Trans Earth Injection (when coasting back from the Moon), the spacecraft's (CSM) guidance platform ...
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How much could “sublimator operation” have possibly contributed to Apollo 11's “sizable downrange miss”?

This answer to the question Apollo-11 delta-v “due to residual pressure in the docking tunnel pushing the spacecraft apart” detected as it happened? Was it corrected? quotes from the Apollo 11 Mission ...
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Which module had more 'comfort' in terms of living space, the Lunar Module or the Command module?

Where were the astronauts more comfortable spending the day, sleeping, donning space suits, etc: the LM or the Command Module? Considering, of course, that the Command Module would carry three crew ...
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What did the Apollo missions do with old LiOH canisters & the water they produced?

We all love the Apollo 13 story, but the famous lithium hydroxide CO2 scrubber of that mission has made it hard for me to find information about its regular use. What happened to the old canisters ...
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Help understanding how these components of a Honeysuckle Creek dish antenna work

@Fred's comment links to the Curious Droid video How Australia Helped Save Apollo 13 and a little after 02:15 and 03:00 it shows ...
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How many people spoke to Apollo 8 from outside the US?

@PearsonArtPhoto's answer links to the page Apollo 8, 21 – 28 December 1968 by Hamish Lindsay at honeysucklecreek.net. It shows a clipping from The Canberra Times front page, "With thanks to Mike ...
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What angle of ascent did the LEM use to leave the moon? [duplicate]

I've been playing around with lunar launch delta-v requirements, and it seems that you can get a lot of bang for your buck if you launch "sideways" so to speak. Well, in the absence of atmosphere ...
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Apollo altitude vs rate-of-descent schedule

In the final phase of the Apollo landings, the commander would go into "P66 attitude hold" mode, where the computer maintained a steady rate of descent while allowing the commander to change ...
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Why did Apollo spacecraft use both AC and DC equipment? Still used in present and future designs?

Why did the Apollo spacecraft use both DC and AC power, requiring heavy inverters? Was it impractical to design everything to run on DC power only? Why? Are both AC and DC power still used in present ...
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Apollo 11 trajectory logs [duplicate]

is there any place where to download the log files of the entire Apollo 11 mission? I want to rebuild it in Matlab and I'd use it as reference. I've seen that there is AGI's reconstruition with STK, ...
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Apollo PTC roll orientation and communication with earth

I have a 2 part question. With the Sun, Earth and Moon on the same plane, I do not understand the difference in heat distribution between perpendicular or parallel orientation with reference to the ...
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Source for Apollo 11 descent time series data?

I'd like to find the state of the Apollo LM at various times during the powered descent phase: its position relative to the Moon's surface and/or the final touchdown point; its attitude in space, and ...
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Why are there double shadows in this Apollo 14 magazine?

In magazine AS14/KK there are clear double LEM shadows present where only one should be. I can't find any evidence of double exposure. How did this happen? I've even found 2 shadows that overlap and ...
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Has there been any serious prospect of human landing on the far side of the Moon?

As far as I know, the only serious projects for human exploration of the Moon have been the Apollo project, some other US studies with Gemini capsules and a couple of embryonic Soviet projects. I see ...
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Who are these people inside Apollo Command Module (presumably posing for advertisement photoshoot)?

In an attempt to find photos from any of Apollo missions that portray Sony TC-50 voice recorder/player that was used in these missions I came across the following picture: There is better quality of ...
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What was the transmitting power of the Apollo astronauts' PLSS VHF radio transmitters?

I'm assuming many of you are familiar with Larry Baysinger. A radio amateur who independently detected and recorded the transmissions from the Apollo 11 EVA using a homemade antenna. Larry Baysinger ...
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In multiple parachutes, is each offset by a weight/hole?

Source: NASA via wikimedia.org As the image shows, in multiple parachutes, each assumes a position away from the center. The post, Why don't 3-parachute descent systems collide and collapse?, ...
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How exactly did the separation between Saturn V stage 3 and the Command / Lunar Module work?

After Apollos 3rd stage burn to get to the moon the Command Module (CM) turned around and pulled the Lunar Module out of the 3rd stage. Both the CM and the LM turned around and flew to the moon. But ...
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What was mylar used for on the Apollo Command Module space craft? Why is it gold after returning from space?

I lived in Hawaii when Apollo 15 returned from the moon. I saw the crew return by helicopter from the ship to Hickham A.F.B. and when the helicopter carrier, the USS Okinawa (LPH 3), returned to ...
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How was the S-IVB stage configured for the post-extraction retrograde dump?

When answering How exactly did the separation between Saturn V stage 3 and the Command / Lunar Module work? I first wrote that the retrograde dump after LM extraction happened "through the engine". ...
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Apollo 11 mission report shows velocity well below escape velocity thousands of km on the way to the Moon

This is from the Apollo 11 mission report. It says the vehicle was going at 7.6 km/s when the CSM separated from the third stage. It was not in orbit at this point, it was thousands of KM from earth. ...
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How many burns did the Apollo 11 mission need?

I'm wondering just how many burns the Apollo 11 mission required. Did they first have to reach a circular orbit around Earth by a single burn at apogee or did they target the Moon immediately? Then, ...
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If I wanted to reconstruct an entire Apollo mission's crewed spacecraft trajectories, what are the key sources of historical data I'd look for?

The last few images in Robert A. Braeunig's Apollo 11's Translunar Trajectory; and how they avoided the heart of the radiation belts are fascinating and a bit perplexing as discussed in this answer ...
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Why is there no image of the Earth taken from the lunar surface during Apollo 12,15 and 16?

I know there are photographs of the Earth from the lunar surface taken during Apollo 11, 14 and 17. Here are some for reference (there are many for Apollo 17). Apollo 11 (AS11-40-5923): Apollo 14 (...
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Did the Apollo missions fly “over the top” of the Van Allen radiation belts?

In the video The Moon Trees That Flew To The Moon On Apollo 14 after about 08:47 Scott Manley says that Apollo 14 "flew up over the top" of the Van Allen radiation ...
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How much did it cost to rush the Apollo program? [closed]

We know how much the Apollo program cost: The United States spent \$28 billion to land men on the Moon between 1960 and 1973, or approximately \$288 billion when adjusted for inflation. Source ...
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How hot was the surface of RTG radiator which powered ALSEP on Apollo-12?

The last 5 Apollo missions that landed on the moon (starting from Apollo-12) deployed Apollo Lunar Surface Experiments Package (ALSEP) which was powered by radioisotope thermoelectric generators (RTG) ...
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Exactly how does one lope on the Moon?

This answer includes several quotes from apollo astronauts that have walked on the moon. They describe a form of bipedal locomotion they call loping. Question: Exactly how does one lope on the Moon? ...
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How much piloting did the Apollo astronauts actually do?

I understand Armstrong landed the Eagle manually, and Apollo 13 did a manual burn. Other than emergencies like that, did the Apollo astronauts do much piloting of the spacecraft.
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What biomedical data indicated Apollo astronauts were sleeping?

What particular biomedical data did NASA use to determine if an Apollo astronaut was awake or asleep? From the APOLLO 11 MISSION COMMENTARY, page 72/1 "Our Flight Surgeon reported a short while ago ...
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What was pressure and temperature of LM oxygen tanks?

After analysing comments in related question How cryogenic oxygen was heated up for CM cabin repressurization? It appears that LM had oxygen stored as either gas or supercritical fluid but not at ...
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What was back-up plan in case of Apollo CSM Primary Guidance System IMU went to gimbal lock?

In Apollo-11, during preparations for docking with Command and Service Module in lunar orbit, Armstrong and Aldrin managed to put Lunar Module Primary Guidance System Inertial Measurement Unit (IMU) ...
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How would the state vector be updated in the Apollo Guidance Computer during coasting to/from the moon if communication with Earth was lost entirely?

This source https://www.hq.nasa.gov/alsj/alsj-average_g.html states that: From time to time, Houston could update the onboard SV using tracking and other available date; [sic] but, generally, it ...
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What do these Apollo era terms mean?

@Ludo's answer to If I wanted to reconstruct an entire Apollo mission's crewed spacecraft trajectories, what are the key sources of historical data I'd look for? links to Apollo Mission 11, ...
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How intrusive was the Apollo Master Alarm system?

During the Apollo 11 landing, a misconfiguration caused the guidance computer to activate the 1201 and 1202 program alarms, signifying that the computer was overloaded and dropping low-priority tasks. ...
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Why was the Apollo CM main engine thought to be unreliable on Apollo 13?

When Apollo 13 had most of its internal systems destroyed by an explosion, NASA decided that the best course of action would be to fire the main engine on the dark side of the moon to send the capsule ...
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Apollo CM heat shield burnt pattern around RCS thrusters

Looking through photos of Apollo CM capsules after reentry, I was trying to have a feel for how the heat was distributed on the sides of the capsule. By the look of surviving patches of Mylar tape ...
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Apollo lunar mission trajectory animation

Is there any animation of real trajectory (and real velocity profile) of any of the flown Apollo moon missions? Something similar to what is shown in the two following links, but using actual data ...
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Could an Apollo crew have been killed by Solar radiation?

The Sun throws lots of high speed protons around. Especially during its sudden and short intensive "events". Much of that is blocked by Earth's magnetosphere and atmosphere. But astronauts work ...
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Did any of the Apollo lunar modules land significantly off level?

I'm pretty sure I recall some images of a lunar module sitting on a slope, although perhaps it just looked that way due to a tilt of the camera. Anyway, my question is: whether any of the lunar ...
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What is known about the trajectory of J002E3 (Saturn V IV-B stage of Apollo 12)?

This answer taught me about J002E3, an object detected in Earth orbit in 2002 that is assumed to be the Saturn V IV-B stage from Apollo 12. It's trajectory through space is fascinating: (source) ...
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How did LM circuit breakers operate? (famous engine arm CB broken by Aldrin)

From Apollo Lunar Surface Journal: "112:56:28 Aldrin: Houston, Tranquility. Do you have a way of showing the configuration of the engine arm circuit breaker? Over. (Pause) The reason I'm asking is ...
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Does trajectory of an object orbiting a planet depend on the object's mass? (With hypothetical Apollo example)

For example (hypothetically), if an Apollo crew of one of the lunar missions went on EVA just after Trans Earth Injection burn and carefully released a small bolt, or a plastic package from their food,...

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