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 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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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 ...
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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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What was an “insurance cover”?
The drawing below reads "This insurance cover is from my personal space collection. Charles M. Duke Jr." What was an insurance cover?
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Were the Apollo mission ascent stages left in graveyard orbits? [duplicate]
After reading this question, I was left with the question of what happened to the ascent stage of the LEM after rendez vous with the CSM.
Obviously it didn't reenter with the command module, and I ...
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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 were the “dust recepticles” installed on the Apollo 17 LM floor?
This answer quotes Apollo Program Summary Report and includes the sentence:
During the Apollo 17 mission, dust on the lunar module floor was swept into floor receptacles which were sealed before ...
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Was there any approval to interrupt the Apollo program for 2 years for Skylab?
In researching an answer for another question, I came across this claim on a NASA history page:
On September 2 [1970] Paine called a press conference to announce NASA's interim operating plan for ...
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Was the lunar landing site always in the same plane as the CM's orbit?
Did the Apollo command module always pass directly over the lunar landing site? Or were they sometimes in different planes?
My inclination (pun intended) is that staying in the same plane would ...
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Are there photos of the Apollo LM showing disturbed lunar soil resulting from descent engine exhaust?
Are there any photos of the Apollo LM descent engine bell and the lunar soil beneath it disturbed by the engine exhaust?
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Were there any mission goals for the Apollo 18, 19, 20 flights?
I recently learned that Apollo 18, 19, and 20 missions were planned before they were canned due to budgetary reasons.
I've only been able to find out the projected landing locations for these (...
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How did the Apollo survival kit desalter work?
According to the Apollo Experience Report: Crew Provisions and Equipment Subsystem, NASA Tech Note D-6737, p. 29, the survival kit in the Apollo command module had a means to remove the salt from ...
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What is the furthest distance Apollo astronauts can be from each other during a Lunar EVA?
I'm assuming there has to be a limit set by NASA of how far astronauts can be from each other for their safety. If something happens to an astronaut's EVA suit, the second astronaut can use the "buddy ...
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Did a flight controller ever answer Flight with a no-go?
OK, all flight controllers, I'm going around the horn
Retro? Go
FIDO? Go
Guidance? Go
Control? Go
TELCOM? Go
GNC? Go
EECOM? Go
Surgeon? Go
Are there any ...
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What did the Apollo 12 multispectral Four-Camera system look like?
From Apollo 12 Mission
The camera equipment carried by Apollo 12 consisted of one 70-millimeter Hasselblad EL camera, two Hasselblad data cameras, two 16-millimeter Maurer data acquisition cameras, ...
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How did Apollo 15's depressurization work?
Artwork depicting the EVA in question, NASA, via wikimedia.org
On the way back an EVA was performed, and since there wasn't an airlock, the Command Module was depressurized.
Was this feature only ...
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Why did no astronaut land on the moon more than once? [duplicate]
Wouldn't it be better to send people to the moon that already have experience?
Or was the time between the starts so short that it was not possible to reuse the crew of Apollo 11 for (say) Apollo 17?
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Why did Mercury use multiple CAPCOMs while Apollo did not?
A spacecraft needs multiple receiving stations to prevent its radio signals from being blocked by Earth. Wikipedia has a map of the ground stations used for the Mercury missions.
The Right Stuff ...
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How did astronauts get from the command module into the LEM, and vice versa?
After seeing many simulations of the command/service module doing a 180 and docking with the LEM, it occured to me that something didn't look right. At the nose of the command module there appears to ...
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Puzzler: which Apollo 8 astronaut would have been positioned furthest sunwards 20 minutes after lunar insertion?
This Classic @DavidHammen answer to the question Who has been the closest to/furthest from the Sun? says:
This bodes well for an Apollo astronaut being the person closest to the Sun, but bodes ill ...
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Double redundancy for the Saturn V LVDC computer memory, how were disagreements resolved?
In the Smarter Every Day video How did NASA Steer the Saturn V?- Smarter Every Day 223 Destin is talking with Luke Talley about the memory modules used in the Saturn V LVDC computer.
This computer ...
