Questions tagged [apollo-11]
Apollo 11 landed the first humans, Neil Armstrong and Buzz Aldrin, on the surface of the Moon on July 20, 1969.
73
questions
12
votes
2answers
2k views
What are the “18 rescue missions” on Apollo 11, and which 10 of them did Michael Collins not feel comfortable with?
Regarding this tweet from the man himself. I take it to mean abort modes in some form or other for the entire mission? Perhaps just after LM descent? What are the 18 failure modes, and (if there's any ...
1
vote
1answer
81 views
How was a safe tilt angle ensured for liftoff of the Apollo LM?
Recently I read that one of the pre-conditions (among many others) of a successful lift off of the LM ascend stage, from the moon surface, was that the LM ascend stage "axis" should be "...
2
votes
1answer
79 views
What is the constant g-phase in Apollo re-entry, and why does it not show up on the graph?
On the Apollo 11 Flight Journal Day 9: Re-entry and Splashdown, it says something about the "Constant g-phase". This is what the ALSJ says:
Planned drag level (deceleration) during the ...
5
votes
1answer
109 views
What were these bent clamps at the top of Apollo 11 CM used for?
An image of the top of Apollo 11 CM from heroicrelics dscc9638 and dscc9660.
What were these bent clamps (marked with green arrows by me) used for?
7
votes
1answer
101 views
What was the nature of the communication problems during Apollo 11's Eagle's descent? How were other antennas selected?
In the video of Los Angeles station KTLA's Frank Buckley interviewing astronaut & Apollo 11 CAPCOM Charlie Duke a communication problem and antenna selection is described:
BUCKLEY: Many of us who ...
4
votes
1answer
92 views
Apollo 11 first stage separation
Did Apollo 11 climb vertically upwards i.e. radially outwards, or "normal" to earth surface till it separated its first stage (approximately 38 Miles/60 Km or so..), or did it tilt at or ...
-2
votes
4answers
208 views
Computers for Apollo Mission
Why did NASA invest so much amount of time and money on developing computers for Apollo Missions? Wouldn't the Man on Moon mission have been far easier and faster if the Astronauts drove the ...
21
votes
2answers
4k views
Why did Apollo 11 land at the sea of tranquility?
As we all know in 1969 Apollo 11 landing made history but, why did it land specifically at the sea of tranquility also known as Mare Tranquilitatis. Probably they would have chosen this because of ...
26
votes
1answer
1k views
How did they access the LM to mount the flag package while the Apollo stack was already on the launch pad?
NASA decided rather late to take a flag to the Moon on the Apollo 11 mission. In fact, they were so late that the package containing the flag was only attached to the leg of the LM on July 9th, two ...
5
votes
1answer
88 views
What happen to the Smithsonian Institutes 3d scan of the Apollo 11 Command Module?
"Since its landing on July 24th, 1969, the Columbia has been kept sealed in plexiglass at the Smithsonian Institute in Washington, DC. That is, until recently, when the software company Autodesk was ...
1
vote
0answers
37 views
Was there any effort made to have Apollo 11 land on July 4? [duplicate]
President Kennedy set a goal of landing a manned mission on the moon by the end of the 1960s, as stated in his well-known speech to Congress on 25 May 1961 ("I believe that this nation should commit ...
7
votes
2answers
423 views
apollo 11 moon landing longitude latitude from PDI to Touchdown
I'm reconstructing the entire apollo 11 mission trajectory.
I'm now at the moon landing. Does someone know specific documents specifying longitudes and latitude at the different interfaces starting ...
1
vote
0answers
35 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 ...
9
votes
1answer
675 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?
...
4
votes
0answers
104 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, ...
2
votes
1answer
166 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, ...
5
votes
1answer
230 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
920 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 ...
5
votes
2answers
275 views
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 ...
5
votes
1answer
160 views
Why did a phase mismatch between the Apollo 11 LM's RR and AGC generate a large numbers of interrupts?
A critical aspect of the cause of the famous 1202 and 1201 alarms reported by the Apollo Guidance Computer (AGC) during the decent of the Apollo 11 LM is that the rendezvous radar (RR) was using a "...
7
votes
1answer
203 views
Where in orbit was Michael Collins when the LM landed?
In the NPR podcast On Apollo 11 Anniversary, A Former Crew Member Reflects On The Lunar Trip Scott Simon interviews Michael Collins. Near the beginning is this exchange:
SIMON: We asked the man who ...
12
votes
2answers
3k views
Did the 1202 error and associated reboot prevent disaster on Apollo 11 landing?
Most accounts of the famous 1202 error reported by the AGS during landing of the Apollo 11 LM characterize the event as result of the successful operation of the AGS, flushing an resetting an ...
5
votes
1answer
499 views
Help understanding this Apollo 11 docking probe image, what are we looking at, and from where?
The New York Times mix media "article" Apollo 11
As They Shot It shows original photographic images taken by the astronauts and related quotes by them.
In one section the text says:
...
1
vote
0answers
59 views
What's the “thump” I hear listening to Apollo 11 playback?
I've been listening to live playback of the Apollo 11 mission at https://apolloinrealtime.org/11/
Besides the expected static and hums, from time-to-time I hear a "thump", sometimes one, sometimes ...
7
votes
1answer
221 views
How much could “sublimator operation” have possibly contributed to Apollo 11's “sizable downrange miss”?
This answer to the question Apollo-11 delta-v “due to residual pressure in the docking tunnel pushing the spacecraft apart” detected as it happened? Was it corrected? quotes from the Apollo 11 Mission ...
4
votes
1answer
112 views
What are “uncoupled attitude maneuvers” and why do them?
This answer to the question Apollo-11 delta-v “due to residual pressure in the docking tunnel pushing the spacecraft apart” detected as it happened? Was it corrected? quotes the following passage from ...
8
votes
1answer
363 views
Apollo-11 delta-v “due to residual pressure in the docking tunnel pushing the spacecraft apart” detected as it happened? Was it corrected?
This answer to How far off did Apollo 11 land? mentions that:
Eagle was already 3 miles downrange from the expected position at the start of descent, due to residual pressure in the docking ...
21
votes
2answers
4k views
How far off did Apollo 11 land?
Armstrong wasn't able to land exactly in the designated landing location, as far as I know it was too rocky. So he had to fly a bit farther to find a suitable spot. But how much farther from the ...
6
votes
1answer
193 views
Why was the Apollo 11 in-flight video better than the moon landing video?
Using the incredible site: https://apolloinrealtime.org/11/ as it replays the entire mission in real-time.
One great feature is that the site plays the in-flight TV transmissions that the crew made ...
27
votes
5answers
5k views
What were the problems on the Apollo 11 lunar module?
In the movie First Man we see that there were problems with some button, when Buzz said "We should tell them about that." Also there was an alarm, that they then turned off.
8
votes
2answers
6k views
What was the temperature of the Apollo 11 moon landing zone?
It's soon 50 years from the Apollo 11 moon landing, so in honor of that event, I decided to post a question here.
I understand that moon has due to its long day and long night and also due to the ...
11
votes
2answers
3k views
Could the crash sites of the Apollo 11 and 16 LMs be seen by the LRO?
This BBC article mentions that the crash sites of the Apollo 11 and Apollo 16 Lunar Modules are unknown. The Lunar Reconnaissance Orbiter has mapped most of the moon’s surface at 100m resolution and ...
9
votes
1answer
259 views
What's the “big monstrosity” mentioned by the Apollo 11 crew?
Mission day three, sitting in lunar orbit, the LM docked to the CM, and this conversation happens:
What are they talking about? "Little fluorescent circles"? "All the engineering that went into ...
4
votes
2answers
225 views
Luna 15 - Any official confirmation of objectives?
Russia's Luna 15 crashed into the lunar surface shortly after Apollo 11 landed.
It's widely considered a failed sample return mission, but did Russia ever officially announce that sample return was ...
19
votes
1answer
2k views
Who filmed the Apollo 11 trans-lunar injection?
In the recent Apollo 11 documentary we're shown footage of the mission undertaking a 'trans-lunar injection' burn after having conducted two orbits of the Earth.
Who was filming this sequence?
3
votes
1answer
907 views
How serious was the leaky hydrogen valve on the Apollo 11 mission?
The recent Apollo 11 documentary highlighted that the rocket suffered a 'hydrogen valve leak' in the hours prior to launch. Technicians were still trying to fix it even as the astronauts were boarding,...
6
votes
3answers
855 views
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 ...
2
votes
0answers
100 views
Why do the two Apollo 11 PSEP solar panels appear to have different backing materials?
The PSEP (Passive Seismic Experiment Package) was powered by a pair of solar panels mounted on extended arms. The one on the left (when looking towards the LEM) appears to have a matt grey backing:
...
2
votes
0answers
238 views
What did Apollo 11's SSTV signal sound like?
The TV signal from Apollo 11 had limited bandwidth, and an oddball format was used to send and convert the signal.
All of the modern SSTV demos I've seen on YouTube seem to take around a minute to ...
1
vote
1answer
384 views
What is the meaning of “Bravo”?
There is movie called, " First Man (2018), which is about Apollo 11 mission. CAPCOM-APOLLO 11 speaks to Apollo 11 crew:
CAPCOM-APOLLO 11: Apollo 11, now entering lunar orbit. Your roll
should ...
5
votes
2answers
313 views
How soon after “The Eagle” landed did they first attempt to bounce a laser off the Moon? When did it first succeed?
The question When did Houston figure out where the Eagle had landed? says (in part):
During Apollo 11's stay on the surface, Michael Collins was given seven different locations to look for the ...
12
votes
1answer
359 views
When did Houston figure out where the Eagle had landed?
Between starting the descent burn three seconds late, and having to avoid landing in a boulder field, the Apollo 11 descent module almost completely missed the target landing ellipse.
During Apollo ...
4
votes
1answer
430 views
Who were the major manufacturers of the Apollo 11 rocket?
Organizing an exhibition around photographs from the 1969 launch and wanted to invite manufacturers.
6
votes
2answers
346 views
Looking for Apollo 11 powered descent video
At a science museum I visited on my 2018 fall vacation (I think it was the Chicago MSI), I saw a video loop that looked and sounded very much like part of the moon landing multimedia show at the ...
5
votes
1answer
284 views
Transfer of astronauts from CSM to LM
Did the astronauts "remove" the docking probe, the drogue of the LM, and related mechanisms from the CSM to enter the LM of Apollo 11?
6
votes
1answer
2k views
What was the colour of the shoes used by the Apollo astronauts in moon landing?
The pictures from Apollo landing despite being in high resolution, does not reveal the right colour of the shoes used by the astronauts during the EVA on the moon. An example - Buzz Aldrin picture ...
10
votes
1answer
1k views
Why did Neil Armstrong alone, not NASA, end up coming up with the first words uttered on the moon?
"That's one small step for a man, one giant leap for mankind" (Neil Armstrong)
These words are now firmly established in the history of space travel, and at least according to his bio, was concocted ...
5
votes
1answer
335 views
Apollo moon landings - any contingencies for meeting Russians?
I have wondered for years if the Apollo moon missions, especially Apollo 11, had any contingency plans in case they met either aliens or other humans (presumably Russians) on the Moon.
Granted that ...
16
votes
1answer
3k views
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 ...
32
votes
2answers
10k views
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 ...
