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.
532
questions
1
vote
0answers
32 views
Apollo 11 Moon orbital elements [duplicate]
I'm simulating several pieces of the Apollo 11 mission.
I'm now at the point of performing lunar landing sequence, and I'm looking for data. I found this report, but it only has partial data, while ...
3
votes
1answer
44 views
Could Apollo astronauts see other planets with the CM Scanning Telescope?
The Apollo Command Module had the Scanning Telescope for navigating, "Apollo astronaut located a specific star using a single-power, wide-field telescope."
I'm not concerned whether it could ...
3
votes
1answer
142 views
Loose items in Apollo CM during reentry?
Would there have been any danger to the astronauts or the equipment if a soft item, like a crumpled up napkin or tissue, was loose during the Apollo CM reentry, or did everything have to be secured?
8
votes
1answer
187 views
Saturn V Small Rectangles On S-II Stage
On the Saturn V there was a line of several small black rectangles running vertically on the upper part of the S-II stage. What were they for?
edit
here is a picture from the McMahan Photo ...
6
votes
2answers
179 views
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 ...
8
votes
1answer
588 views
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?
...
5
votes
1answer
170 views
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 ...
3
votes
1answer
100 views
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 ...
17
votes
2answers
4k views
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 ...
6
votes
2answers
147 views
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 ...
5
votes
1answer
165 views
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 ...
15
votes
2answers
1k views
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 ...
4
votes
0answers
96 views
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, ...
4
votes
0answers
43 views
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 ...
5
votes
2answers
162 views
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 ...
5
votes
1answer
701 views
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 ...
3
votes
1answer
147 views
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 ...
4
votes
1answer
89 views
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 ...
5
votes
0answers
101 views
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 ...
5
votes
1answer
966 views
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?, ...
5
votes
1answer
123 views
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".
...
11
votes
2answers
1k views
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 ...
1
vote
1answer
172 views
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 (...
3
votes
0answers
104 views
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
...
4
votes
2answers
122 views
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)
...
4
votes
1answer
118 views
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? ...
3
votes
1answer
87 views
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 ...
25
votes
1answer
4k views
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.
10
votes
1answer
666 views
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 ...
2
votes
1answer
132 views
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, ...
6
votes
0answers
149 views
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 ...
16
votes
1answer
2k views
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 ...
22
votes
1answer
1k views
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 ...
10
votes
1answer
1k views
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 ...
4
votes
1answer
103 views
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 ...
11
votes
0answers
179 views
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 ...
4
votes
0answers
147 views
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)
...
5
votes
1answer
191 views
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) ...
10
votes
2answers
694 views
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 ...
6
votes
2answers
600 views
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/...
5
votes
3answers
1k views
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,...
10
votes
1answer
306 views
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, ...
10
votes
2answers
2k views
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 ...
2
votes
2answers
106 views
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 ...
6
votes
1answer
619 views
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 ...
1
vote
1answer
50 views
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 ...
9
votes
1answer
97 views
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 ...
2
votes
1answer
224 views
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 ...
6
votes
2answers
114 views
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 ...
2
votes
2answers
217 views
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 ...
