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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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How much wax is on the Moon? (Lunar Roving Vehicles)

I found the Cody's Lab videos from Scott Manley's video as described in this answer. Browsing through I learned from the first 30 seconds of Hot Wax Bottle? that the phase change of wax was used on ...
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551 views

Who performs the docking procedure?

In the Apollo moon missions when the LEM returned to the CSM, which astronaut performed the docking procedure? Did the command module pilot just hold a fixed position while the astronaut flying the ...
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Two totally different pictures of Apollo 15 landing site released by NASA 40 years apart. What causes these differences? [closed]

A report of NASA, dated December 1971, shows at page 18 a picture on which the traces left behind by the Apollo 15 mission are superimposed. In 2012 NASA released a computer enhanced photo of the ...
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How was the Apollo IMU calibrated?

Both the command and lunar modules of the Apollo spacecraft has navigation systems with inertial management units. IMUs are known to drift over time. How were they recalibrated? My answer below ...
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Did the Apollo 7 “mutiny” have consequences for ground crew?

The Apollo 7 mission was a troubled one due to the crew's illness and resulted in several heated discussions between the flight crew and ground crew. It seems to me that the ground crew was partly to ...
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How does the Apollo LM ascent guidance program P12 actually work?

P12 is the AGC guidance program for normal ascent from the lunar surface to orbit. According to the mission planning documents, after separation and ignition, the ascent stage holds its initial ...
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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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How would the Apollo telescope have worked in the Apollo command module? Where would it be located and how would it be operated?

In the Vintage Space video episode Missions we Lost When Apollo was Cancelled, there is discussion of the Apollo Telescope and the Block 3 command module after about ...
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In what ways did the high elliptical orbit of Apollo “E missions” simulate lunar missions?

The vintage space video Missions we Lost When Apollo was Cancelled after 01:25 describes classification scheme for then-future Apollo missions: As Apollo took ...
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How long would a stranded Apollo crew have survived on the Moon?

If the Apollo ascent vehicle hadn't been able to take off from the Moon, how long was the crew expected to have survived? And what would the likely natural cause of death be? I've heard that partial ...
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2answers
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Arcustangent function of the Apollo Computer, atan() or atan2()?

What type of the arcustangent function was used, the one with single argument only or the famous atan2(y, x) or arctan2(y, x) with two arguments x and y? What kind of aproximation was used?
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At what size of engine does pogo oscillation become significant

I am jist trying to understand the thresholds involved in pogo oscillation. I'm not sure where to start. But I will give a guess. As rocket size increases the tension exterted on rocket walls ...
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Did Michael Collins ask for a fourth gimbal for Christmas? Is there a recording or transcript?

Did Apollo 11 Command Module Pilot Michael Collins ask for a fourth gimbal for Christmas, while looking for the lunar ascent module? If so, is a recording of this available for posterity? Or a ...
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How did the Apollo computers evaluate transcendental functions like sine, arctangent, log?

Navigation with a sextant or maneuvers using gimbal angles might be two examples of cases where an Apollo computer might need to do trigonometry. Trigonometric functions like sine, arctangent, etc. ...
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Usage of Apollo Lunar Surface Hasselblad Camera with 500 mm lens?

Here is a list of photographic cameras used for Apollo 16. There were two Lunar Surface Data Hasselblads equipped with a 60 mm lens for both astronauts to be used with chest mounts to the space suits....
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Was the lunar module computer in the ascent stage or the descent stage?

Two Apollo Guidance Computers accompanied each lunar mission. One CPU was housed in the lower equipment bay of the command module, with one DSKY display-keyboard unit adjacent to the CPU, and a ...
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Revisiting moon landing sites?

Are there any current plans to return to the moon, preferably close to an existing landing site? After all, it seems like a sound scientific project given that there's talk of human colonization of ...
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What colors were used in the Apollo Lunar Module interior, and why?

There are lots of publications and blog posts on the exterior colors of the Apollo Lunar Module (a function of material choices), but I've struggled to find any information on the interior colors and ...
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Why didn’t the Spacecraft used for the Apollo 11 mission melt in the Earth’s Atmosphere?

My brother has recently been converted to a Flat Earther and is convinced that something that proves his theory is the moon landings being faked by NASA. I have managed to counter argue the majority ...
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Apollo-11 AGC core memory has 5 wires per core (rather than 3 or 4) - why?

Apollo-11 AGC core memory has 5 wires per core (rather than 3 or 4) - why? I am referring to this image in Wikipedia: https://en.wikipedia.org/wiki/Apollo_Guidance_Computer#/media/File:...
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Apollo-SLA & LM air pressures at launch

At the time of launch what was the air pressure in the Apollo LM, and the spacecraft-LEM adapter section (SLA)? Was the air vented from the SLA as the vehicle entered orbit?
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Apollo J Mission CSM- EPS Radiators

Were the EPS radiators on the J Mission CSM's upgraded or enlarged to accommodate the increased electrical load imposed by the sim bay equipment?
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Apollo 10: Where's Snoopy?

During the Apollo program, we launched a total of 9 Lunar Modules (LM's). The Ascent module from Apollo 10, or "Snoopy," is unique in that it was neither deliberately crashed into the Moon (Apollo 11, ...
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Why was orbital rendezvous considered so controversial?

It's popularly understood that the Apollo program only selected lunar-orbital rendezvous as a mission profile after first thoroughly rejecting the direct ascent profile. It seems as though the ...
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What physiological effects did the Apollo astronauts experience due to the lower lunar gravity?

When humans are exposed to weightlessness they often experience space adaptation syndrome (similar to motion sickness). Also fluid redistribution to the upper body is nearly immediate causing bulging ...
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Apollo simulator practical jokes

The Apollo training program as described in this question used a computer driven system of servos and motors to move cameras over and around models. This type of simulator was common in aviation ...
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NASA at sIxty years, will there be a new moonshot mandate?

NASA is sixty years old still going strong. There are few organizations that have made such an impact to man's quest for knowledge in such a short time span. The contributions are many, and its ...
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Apollo training simulator cgi requirements

https://ohiostate.pressbooks.pub/graphicshistory/chapter/13-4-nasa/ says that cgi was used for Apollo trainers. I just want to know the quality of this cgi. A modern computer runs at 2560 lines on ...
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How much cgi would be needed to fake apollo [closed]

A modern CPU is 200 gflops. A 1968 computer is 5 mflops. A few weeks to render a minute of footage. So since there are only a few minutes of physically relevant footage (lunar rover dust trajectory, ...
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For an Apollo Lunar Module Ascent Stage launch, what is the optimal profile of $\beta$ (or $\gamma$) vs time?

When Apollo astronauts departed the lunar surface in the Lunar Module's Ascent Stage, it appeared to rise vertically ($\beta$ = 0) for ~10 seconds and then begin the "tipover" (videos of Apollo 15, 16 ...
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Would we be able to see a Space craft transit in Lunar orbit?

If a Apollo type Moon mission happened today would we be able to see it transit in Lunar orbit? I know we can't see the Landing sites of the Apollo but could we see the Command Module and its shadow ...
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Did Apollo have provisions for “system aborts” during ascent?

The Shuttle flight rules provided for launch aborts if the vehicle suffered severe failures: cabin leak, loss of cooling, severe electrical problems, etc. These rules were in addition to the rules ...
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In what ways did the Soviet Union “observe the Apollo Moon landings closely”?

@DarkDust's comment says: If the USSR had had just a tiny amount of doubt whether the landings were faked, they would have used that for propaganda. Loudly! They observed the landings closely and ...
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How do we know the Apollo Moon landings are real?

Since about 1976, conspiracy theories denying the Moon landing and claiming it was all faked have cropped up. As a website devoted to answering questions about space exploration, we receive questions ...
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1answer
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Apollo Command Module's impact attenuation system, what did the inner part look like?

A reference used in Wikipedia's Apollo Command/Service Module article is CSM06 Command Module Overview pp 39-52.pdf. It includes (bottom of document page #43, 5th page of pdf): Imact Attenuation: ...
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1answer
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What does “angle of attack 100%” mean in Apollo abort rules?

In Apollo Mission Rules and Saturn V Flight Manuals, I have seen the following abort rules: I understand what most of this means -- if the launch vehicle begins turning at more than 4 degrees per ...
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Could “peak Apollo levels” of support have gotten NASA astronauts to Mars in the 1980's?

In an "alternate universe" where NASA continued to receive a mandate, funding and public support at say peak Apollo levels, could another ten or twenty years have gotten boots on Mars, with astronauts ...
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Lunar rover footage?

How many hours of publicly available footage is there of the lunar rover moving around? Youtube only has 2 min. I want more. Especially with rooster tail.
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3answers
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How did NASA prevent third parties from spoofing Apollo communications?

The Apollo crews transmitted footage to Earth using SSTV, a ham radio technique that amateurs and pirates can use to send similar messages around the world. Did NASA have any technical ...
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1answer
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Observing a lunar lander by telescope

It is said that a 25m telescope would render the lunar lander as 1 pixel. However the lunar surface has an albedo of about .1 while the lander is highly reflective. So it would be about 10x brighter ...
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What is the cause of the data discrepancy between these two Apollo 11 Reports

Table 7-11 on page 7-9 of MSC-00171 Apollo 11 Mission Report lists the CSM/S-IVB separation occurring 3 hours, 17 minutes and 4.6 seconds into the mission, at an altitude of 4110.9 nautical miles, at ...
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1answer
126 views

Lunar dust trajectory only slightly different from earth?

http://www.popsci.com/sites/popsci.com/files/styles/medium_1x_/public/import/2014/Hsu%20and%20Horanyi%20Graph%20AJP.png?itok=OSqMRad6 This graph shows the observed trajectory of lunar rover dust ...
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CSM velocity / apollo program

Reposting as a question. Uhoh's answer allows us to compute the velocity at a given r. Let's see what velocity is at $r=100000 \text{ km}$: \begin{align}\mathscr{E}_{tot} &= {1\over 2}v^2 - {...
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1answer
441 views

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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2answers
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Was the Saturn V only going at 1.1km/s after the first stage?

Using data from Wikipedia and NASA, I compute the Saturn V velocity after jettisoning the first stage (S-IC) \begin{align}V &= \ln(M_{initial}/M_{final}) \times V_e - g \times T_{burn}\\ \\&=\...
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Saturn Ivb accelerated [closed]

https://en.m.wikipedia.org/wiki/Saturn_V Derivation of a variant of the Tsiolkovsky rocket equation which includes gravity Take the rocket equation : v = ln(m0/mf) ve - g tburn Where tburn is time ...
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Can I find detailed flight parameters of some space mission(s)?

I'm studying dynamic models and creating a mathematical model for spaceflight simulation. I need to check the correctness of my model. Can I find detailed parameters of a spaceflight (say, position ...
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Why was Apollo mission launched on one big rocket? Wouldn't rendezvous in earth orbit using a smaller rocket have been an easier challenge?

Apollo already had some hardware for rendezvous on lunar orbit, so why not do the same on earth orbit and use smaller rocket? I suppose designing smaller rocket is simpler and also building double ...
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Why was the Apollo 6 service module painted white?

All other SM's were silver except Apollo 6. I'm wondering what the justification for this was, if any?
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Where did the famous “end of decade” deadline come from?

In his address to Congress on 25th of May 1961, John F Kennedy committed for the first time to land a man on the Moon and bring him safely back before the end of the decade. But the feasibility ...