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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189
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Can I borrow a lunar rover?

According to Wikipedia there are 3 LRVs sitting on the moon, in very well defined locations. Would China, or whomever gets to the moon with a person next, be able to get in and drive around in an LRV ...
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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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Why not build Saturn V's again?

Why is the US developing a new rocket and spacecraft as opposed to building the Saturn V and Apollo stacks again? The SLS / Orion development programs certainly can't cost less than the unit cost of ...
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How did NASA achieve their live TV broadcast in 1969?

In 1969, NASA not only went to the moon, but broadcast the whole thing live on TV. How did they achieve the TV broadcast? What technology did they need to use to send a video and audio signal from ...
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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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Launch Accelerations: Values, history

This topic: What G-forces do different launchers cause? indicates that current satellite launchers are limiting peak acceleration to about 4g. I'm pretty sure the STS (Shuttle) did the same. My ...
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How did the Apollo 11's Eagle ascent stage find the CSM after leaving the Moon?

I've always been curious how did the Apollo 11's Eagle ascent stage of the Apollo Lunar Module navigate back to the Apollo Command/Service Module (CSM) that was in lunar orbit? Was it simply a case ...
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Did astronauts on the moon poop in front of each other?

I know about the Apollo pooping bag. The question is, in the CSM, was there any space to use it privately? I suppose while coasting towards the Moon they could use the LM, but on the return trip? Any ...
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What are these structures on the Lunar Ranging Retro Reflector (LRRR) arrays for?

In this question I used images of the retro-reflector arrays that were left on the moon by Apollo 11, 14, and 15. The Lunar Ranging Retro Reflectors (LRRRs) are there for Lunar Laser Ranging. The ...
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Reasons behind the “Transposition, docking and extraction” maneuver

The Transposition, Docking and Extraction (TD&E) maneuver was done during the Apollo Moon missions right after the translunar injection. The Command/Service Module (CSM) separated from the S-IVB, ...
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Were the Apollo lunar activities observed from Earth?

I understand that all manned landings on the Moon were on the near side, so technically they could be visible from Earth. Was it possible to observe landings and/or extravehicular activities (EVAs) ...
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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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Where were the various Apollo Lunar Modules (LMs) discarded?

The LEM was comprised of an ascent, and a descent stage. Whilst the descent stage was in most cases left behind on Luna, the ascent stage ferried the astronauts upstairs to the CSM. Where are these ...
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Did Apollo's velocity slow down after TLI due to Earth's gravity?

I assume Apollo's velocity slowed down after it left Earth orbit, for how long was it decelerating. Did it start accelerating as it approached the Moon. What was the rate of deceleration due to ...
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Puzzler: Precisely what maximum distance from the Earth did the Apollo 13 astronauts achieve?

tl;dr: Both this answer and this answer quote Wikipedia to state that the Apollo 13 astronauts reached 404,171 km from Earth. I'm not able to reproduce that value. According to JPL's Horizons the ...
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How was dust-mitigation addressed during the Apollo program?

Dust mitigation in the context of manned landings is now a rather vital topic of research and testing, but back in the days of Apollo it was a fairly new problem. 'Dusty' Gene Cernan inside the LM ...
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Apollo/Shuttle launch site fuel handling

I read somewhere that fuel was delivered to the Apollo launch site by tanker truck (for cryogenic propellants) and rail cars (for the kerosene). Were the fuels transferred directly from delivery ...
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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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What exactly turned on the light indicating Apollo 8 was starting to fall towards the Moon?

@PearsonArtPhoto's answer links to the page Apollo 8, 21 – 28 December 1968 by Hamish Lindsay at honeysucklecreek.net from where I have quoted below. Question: What exactly turned on the light ...
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Why did Apollo 11 need someone to stay behind in lunar orbit?

When Neil Armstrong and Buzz Aldrin descended to the moon in the Lunar Module, Michael Collins stayed up in lunar orbit in the Command Module. Why did they need someone to stay behind? At this point,...
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How often is duct tape used during crewed space missions?

It seems Apollo missions carried some variety of gray tape, likely Duct Tape or similar. There's the scene in the movie Apollo 13 and the reality behind it discussed in the video below. Question: How ...
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How was reserve fuel calculated for the Apollo missions?

A quick follow-up to How much fuel was used for a Space Shuttle launch? My memory is a little foggy; I seem to recall reading the Apollo 11 mission commander depleted his reserve fuel landing Eagle. ...
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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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Why did the Apollo Lunar Module have four landing legs?

Why did the Apollo Lunar Module have four landing legs? Is not just three legs enough? Also, three legs guaranties they always form a plane, four does not, as the fourth leg may dangle. To have the ...
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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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Did the Apollo lunar module descent stage have a role as a sort of service module?

To minimize the re-entry mass of the Apollo command module, essentially all of the mission supply of command module consumables was stored in the service module. Was there a similar arrangement ...
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Did Apollo-11 astronauts rehearse their photoshoots on Earth?

After asking Have astronauts in space suits ever taken selfies? If so, how? I started to think about the photo below, and especially the cropped and rotated section that I found in the Wikipedia ...
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Were the Apollo 11 astronauts aware of any parts of the Luna 15 mission?

I just learned today about the Luna 15 mission which was a Soviet attempt to land an unmanned probe on the moon which coincided with the successful Apollo 11 mission. Were the Apollo 11 astronauts ...
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Could an Apollo LM land uncrewed?

I believe that Apollo mission control had the ability to upload data and commands to the LM's guidance computer as long as they had an operational communications link. I'm wondering if, from the point ...
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Could a single crew member fly the Apollo LM?

We know that the Apollo astronauts were subject to rigorous medical testing prior to launch, and we know that this caused at least one Apollo crew member to be replaced very late in the process. ...
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Apollo Mission Operations Control Room 2 display, what do these numbers indicate?

There are some really beautiful photos in Ars Technica's NASA’s restored Apollo Mission Control is a slice of ’60s life, frozen in amber See also NYTimes' NASA Reopens Apollo Mission Control Room ...
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How was temperature and humidity maintained inside the Apollo mission capsules?

What mechanism was used to control the temperature and humidity inside the Apollo mission capsules? For example, did they employ an electric heater? Did they utilize solar radiation? Was humidity ...
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How were Apollo spacesuits cooled during simulations/rehearsals on Earth?

The answer and comments to How have space suits dissipated the heat removed from astronauts? explain that the Apollo space suits used the sublimation of ice into the vacuum of space to constantly ...
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Was the Apollo sextant used (or tested) to determine position while in Earth orbit?

The video Apollo Program Guidance and Navigation System 79974 explains that the spacecraft's sextant could be used together with the navigation computer to determine a position fix while in Earth ...
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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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How did Apollo missions solve the cosmic radiation problem?

One of the major hurdles of space exploration is cosmic radiation. How did the Apollo missions solve the radiation problem? NASA would have shielded the astronauts to some level by some material. How ...
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How did NASA choose who descended in the LEM during the Apollo missions?

Referring to the Apollo missions, As many know, during Apollo 11, Michael Collins didn't descend with Neil Armstrong and Buzz Aldrin towards the moon. I can only begin to imagine the sadness of not ...
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What does 'Switch SCE to AUX' mean?

During the launch of Apollo 12 a major malfunction was caused by 2 lightning strikes. See http://www.realclearscience.com/blog/2013/02/apollo-12-struck-by-lightning.html for more info. The solution ...
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Was the Apollo 13 CM guidance computer fully shut down?

I was watching the movie Apollo 13, and one thing struck me as quite odd. According to Wikipedia, [Movie director Ron] Howard went to great lengths to create a technically accurate movie, employing ...
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Did Apollo carry and use WD40?

It appears from this question that Apollo missions carried Duct Tape and used it for in-flight fixups. Did they carry the other half of the "Universal Repair Kit" - WD40 (or similar)? If so, was it ...
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Were the Apollo CO₂ scrubber canister designs unified after Apollo 13?

After the problem realized when trying to put up three astronauts for an extended stay in the Apollo 13 LEM, namely that the square CM CO₂ scrubbers didn't fit in the LEM's slots, were they redesigned?...
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What was the mascon “fix” used by Apollo 12?

According to the mascon entry on wikipedia: At that time, one of NASA's highest priority "tiger team" projects was to explain why the Lunar Orbiter spacecraft being used to test the accuracy of ...
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What would have happened if the skin of an Apollo lunar module was ruptured?

The Apollo lunar module had thin skins of foil for protection / air containment. What would have happened if a hole was made in this skin by a flailing astronaut, screwdriver, asteroid, etc.? Would ...
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How did NASA get the video camera on the Moon to track the LM ascent stage, considering the substantial delay?

The Moon's distance can be as much as about 406,000 km from Earth. That's a round trip light time of roughly 2 x 406,000 / 300,000 = 2.7 seconds or more, depending on how the signal was relayed to ...
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What does burnt Aerozine-50/N2O4 smell like?

The lunar astronauts universally described the smell of moon dust as similar to spent gunpowder. The exhaust gases from the LM's descent propulsion system (which combusts Aerozine-50 with N2O4) didn'...
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Success-fail probabilities for Apollo XI?

Is it known whether probabilities of success vs failure (and specifically fatal failures) were estimated at the time for the Apollo XI mission? Or perhaps some current estimates?
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Picture of equipment left on the Moon?

When people visited the Moon, they left sizeable items behind. I know that taking picture of this from Earth is incredibly hard, but: Did someone try? And what pictures do we have?
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What do astronauts eat for pre-flight breakfast?

I’m currently reading W. David Wood’s rather excellent “How Apollo Flew To The Moon” which details the technological development and execution in reaching the moon with the Apollo program. Part of ...
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Why were there beeps punctuating the voice communications during missions such as Apollo?

Voice communication between ground and spacecraft during missions such as Apollo seemed to be always punctuated by beeps. What was the origin of these beeps? Were they some sort of unavoidable ...
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How did the Apollo guidance computer handle parity bit errors?

The following answers mention the use of parity bits in the Apollo guidance computer: this answer to Bits per core for the different versions of the Apollo guidance computer core rope memory? this ...

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