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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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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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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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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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 the ...
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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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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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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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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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Did Apollo astronauts play on the Moon their pre-recorded music?

Apollo astronauts were equipped with Sony TC-50 cassette voice recorder/player (described in this answer) primarily for recording voice with mission related notes, but they could (and did) listen to ...
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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 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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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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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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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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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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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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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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Were flown lunar rover miniature license plates approved for the Apollo-15 flight?

A page in Space Flown Artifacts describes miniature lunar rover license plates that Dave Scott carried to the moon and back: These miniature license plates were manufactured by Boeing (makers of ...
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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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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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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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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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Reentry without pressure suits in Apollo: was there a formal risk assesment?

In Apollo 11 Flight Journal the following is stated: The crew will make re-entry without suits or helmets on. Although this was a controversial decision on the first Apollo flight, Apollo 7, when ...
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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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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 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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What is the fate of SLA fairings jettisoned from lunar mission spacecrafts?

After TLI burn, just before Transposition, Docking and Extraction, the later design crafts jettisoned 4 pieces of the SLA fairing/shroud. These 4 pieces supposedly would follow similar path as the CSM/...
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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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How did Conrad let Bean drive Apollo 12? Did anyone get in trouble?

In the NPR News item and podcast It's Been 50 Years Since Apollo 12 Landed On The Moon reporter Geoff Brumfiel says: The trip back went smoothly. Conrad let Bean drive the spaceship a little bit, ...
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What antenna is this in an Apollo 15 LM photo?

The video Apollo 15 landing from PDI to Touchdown (found in Why did the Apollo 15 LM violently shake & raise dust after the contact probes touched the lunar surface?) seems to pan across a still ...
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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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How cryogenic oxygen was heated up for CM cabin repressurization?

In related question How was temperature and humidity maintained inside the Apollo mission capsules? the basic concept of conditioning Apollo mission capsules environment is described. After ...
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Mode during apollo landing in cross pointer

In this Question the excellent answer explains from the handbook that the cross pointer input can be either from landing radar or PGNS or AGS. My question is which mode was choosen during the final ...
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Apollo Cross Pointer Working

The apollo LM panel had a cross pointer that displays the horizontal velocity to the pilot. This ideally have to be made zero during landing for soft touch down by pilot My question is, how this ...
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Why did the Apollo 15 LM violently shake & raise dust after the contact probes touched the lunar surface?

I was watching the Apollo 15 landing and I noticed that after the LM surface sensing probes (contact probe) touched the surface, the view was clear which meant no dust was being raised, but all of a ...
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What was the actual Q-alpha limit for Saturn/Apollo launches, and what was the typical max Q-alpha?

Organic Marble's answer to a previous question about Apollo abort limits clarified that the figure of concern was the product of dynamic pressure (Q) and angle of attack (alpha), with the 100% level ...
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When will a moon landing site be visible via telescope?

Telescope technology is advancing. Logically there should be a point where clear images of the landing sites are visible. I am guessing a 1km telescope would be plenty. If we currently have 100m ...
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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 confession, claiming ...
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How (and when) was the RTG in the lunar modules installed?

In this answer, it is explained that the space probes RTG's are not installed until a couple days before launch because of the heat those things generate. Now I'm curious about the Apollo RTGs. From ...
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Apollo image lighting

How does the lighting in this photo work? It is strange.
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Why was Apollo 11 launched in summer?

The question could seems stupid, but I think that best moment to launch a rocket is when temperature is lowest in order to achieve the best performance in a reaction engine. I do not know if there is ...
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Loading tanks for supercritical oxygen and hydrogen on the launch pad, how to achieve low temperature and high pressure?

The Apollo and Shuttle spacecrafts used fuel cells for the production of electric energy and water. The hydrogen and oxygen for the fuel cells were stored as a supercritical fluid at a temperature ...
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Objects that have been on the Moon multiple times

I'm reading Gene Cernan's The Last Man on the Moon and he mentioned that the flag they erected at Apollo 17's landing site had been to the Moon before: it was taken to the Moon by Apollo 11, then hung ...
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How are physical attitude indicators actuated?

The Apollo FDAIs and shuttle ADIs (pre-MEDS) indicated spacecraft attitude with an actual ball that was spun around in a cage. I've seen photos of some of these removed from their cases, but ...
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Could Apollo astronauts see city lights from the moon?

You can see city lights from orbit on the night side of Earth. A lot of science fiction (yes, sorry...it's one of those questions) has dialogue such as "on a clear night you can see XYZ city on the ...