Skip to main content

Questions tagged [lunar-module]

The Lunar Module was part of the Apollo program spacecraft package. It rode into orbit beneath the Command Module and required extraction once there. It consisted of a descent stage (which remained on the Moon after landing) and an ascent stage (to take astronauts back into orbit). Use with the [apollo-program] tag any any appropriate mission tags.

Filter by
Sorted by
Tagged with
3 votes
0 answers
40 views

Pressurisation in the Apollo Lunar Module? [duplicate]

After the Apollo 1 fire, the Command Module atmosphere at launch was 15psi of 60:40 nitrogen:oxygen, which was allowed to vent down to 5psi during the ascent, and then slowly changed over to 5psi ...
John Dallman's user avatar
13 votes
2 answers
2k views

What spares were taken on Apollo missions, and what was left behind? The question of gloves

In the graphic novel based on John Michael Greer's 'The Next 10 Billion Years', there's a haunting picture of the descent stage of a lunar module (the shorter online version, 'Grounded', is here: ...
asylumax's user avatar
  • 233
3 votes
0 answers
201 views

Was TTCA used during the Apollo 11 landing phase?

Neil selected P66, so he used the ROD switch to adjust the altitude rate (he could not use the TTCA throttle). My question is whether he used the X,Y axis translation feature of TTCA or not. The ...
r2limited's user avatar
2 votes
1 answer
337 views

What was the mass of each of the 12 completed Apollo Lunar Modules?

The propellant tanks on the Apollo 10 Lunar Module "Snoopy" was famously left not full. There is an urban myth that it was done to prevent Gene Cernan and Thomas Stafford from having any ...
Mys_721tx's user avatar
  • 976
4 votes
0 answers
146 views

Why did LEM ascent stage swing during flight?

While watching Apollo 17 ascent footage, I've noticed that the camera is swinging quite a bit. It is definitely fixed to a window, so it means that the whole ascent stage is swinging back and forth ...
radical_gale's user avatar
8 votes
1 answer
822 views

On the LM, what is the difference between ABORT and ABORT STAGE?

The LM had both ABORT and ABORT STAGE buttons. What was the difference and in which scenario would each be used?
Andy's user avatar
  • 81
2 votes
2 answers
1k views

How did the Lunar module reached orbit speed?

How does the lunar module of Apollo 11 reached an orbit speed of 1600 meter/second in order to rejoin the CSM (Command/Service Module)? Additional question, Where are the Oxygen & Fuel tanks of ...
Roee Yossef's user avatar
7 votes
1 answer
427 views

What is this beige, pill shaped object on the back of the Apollo Lunar Module?

Is it an antenna, or something else? Image from https://upload.wikimedia.org/wikipedia/commons/0/04/Apollo_11_Lunar_Lander_-_5927_NASA.jpg
BDA's user avatar
  • 71
4 votes
2 answers
442 views

Icy Hot Astronauts [duplicate]

According to the specifications of the Apollo 13 lunar module where the astronauts were during their emergency return to Earth, the walls were about the thickness of a coke can so how were they able ...
H8 Machn's user avatar
6 votes
2 answers
1k views

At what point did the Apollo 11's Eagle extend the landing gear?

I am trying to figure out, during Apollo missions, exactly when the lunar-module extended the landing gear. Was it closer to the time the CM and LM connected in the space rendezvous or did they ...
Bruce Miller's user avatar
39 votes
3 answers
6k views

Why did the Lunar Module have such an irregular shape? Didn't it add weight and complexity?

Given the very stringent mass requirements, why was such a complex design choosen? I think an irregular shape weights a lot more than a squared box, not to mention the complexity to build it. I saw in ...
jumpjack's user avatar
  • 3,033
12 votes
1 answer
1k views

What distance did the Apollo CSM go before turning round to pick up the Lunar module?

I have looked for quite a while to find this out, and as yet have not been able to work out the answer. On the Apollo missions 10 to 17 the CSM had to turn round to pick up the lunar module between ...
Andy Hill's user avatar
  • 121
20 votes
2 answers
2k views

How Did One Stand in The LEM Before Descent? [duplicate]

This is really simple, but i've never seen it discussed. One piloted the Apollo LEM standing up, without many restraints. But before the LEM ignited the descent engine, it was practically in free fall....
Selene Routley's user avatar
9 votes
2 answers
690 views

Could the ascent stage of Apollo 11's Eagle still orbit the Moon?

This video: Is Apollo 11's Lunar Module Still In Orbit Around The Moon 52 Years Later? claims, based on orbital simulations, that there is a chanche that the lunar module of Apollo 11 might be still ...
zabop's user avatar
  • 686
18 votes
3 answers
7k views

Apollo 14-17 - Why didn't they keep the Lunar Module docked as a lifeboat for the way back to Earth?

During Apollo 13, the Lunar Module had to be used as a lifeboat in order to save the astronauts. Then, it was only jettisoned from the Command Module shortly before Earth re-entry (even after the ...
jakob.j's user avatar
  • 299
3 votes
1 answer
663 views

How did "ACA Out of detent" work?

This is a related question about the words said during Apollo 11 as soon as the LM touched the ground. My question is specific to ACA out of detent As soon as the LM touched down on the surface it ...
zephyr0110's user avatar
  • 2,901
2 votes
1 answer
119 views

What is the origin of the Lunar Module in the US Space and Rocket Center in Huntsville, AL?

I recently had a chance to visit the US Space and Rocket Center. While I was there, I saw a lunar module. It is very clear that the ascent portion is a mock-up, but the decent portion looks real, ...
PearsonArtPhoto's user avatar
  • 121k
15 votes
2 answers
2k views

Would the Apollo LM be able to land on Mercury?

If we set aside the question how the Apollo LM got into orbit around the celestial body in question, I wonder which celestial bodies other than the Moon the LM could successfully land on. Mercury for ...
Giovanni's user avatar
  • 389
4 votes
0 answers
358 views

How much open source is the Apollo program today?

What percentage of NASA's Apollo program is considered to be open source as of today? I mean if I wanted to replicate a lunar mission from scratch exactly the same way they did it, regardless of the ...
Kozuch's user avatar
  • 1,453
2 votes
1 answer
516 views

Why doesn't NASA just again build the Altair LM or a modified Apollo LM for the Artemis project?

The Altair lunar module was part of the wonderful Constellation program cancelled in 2010; just the Orion spacecraft has been retained which is to deliver a crew into lunar orbit. The new carrier ...
Greenhorn's user avatar
  • 274
14 votes
2 answers
1k views

Improvements in Saturn V, LM and CSM after Apollo 10

Apollo 10 is considered to be full dress rehearsal for Apollo 11. Did the trial flight of Apollo 10 identify any improvements that were needed in the Saturn V, CSM and LM, to be done before Apollo 11 ...
Niranjan's user avatar
  • 3,758
2 votes
0 answers
61 views

Why did the CM & LM have to be separated at Apollo launch? [duplicate]

I've just read a bit about Apollo 13, and 1 question that kept popping up in my mind when they talked about the docking between the Command module & the Lunar one is that why did they have to be ...
longtry's user avatar
  • 139
2 votes
2 answers
319 views

Mass of the Apollo Lunar Module cabin pressure vessel?

What was the mass of the Lunar Module cabin pressure vessel - that is, the metal structure that contained the astronauts, including windows and hatches, not including internal fittings and equipment, ...
Will Stevens's user avatar
1 vote
1 answer
166 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 "...
Niranjan's user avatar
  • 3,758
4 votes
3 answers
346 views

Comparison of space shuttle, command module, and lunar module window sizes

The space shuttles had a viewing window much similar in looks like the windshield of a car, or like the cockpit of a plane. However, neither the Apollo command module (CM) nor the lunar module (LM) ...
Niranjan's user avatar
  • 3,758
3 votes
1 answer
219 views

What other options to egress the Apollo Lunar Module were considered, given the height of the LM hatch above the ground?

The egress hatch of the LM is almost 3.5 meters above the Lunar surface. The astronauts descended using a ladder, which is actually quite high above the ground (see also this question). Were any other ...
Ludo's user avatar
  • 14.4k
7 votes
2 answers
866 views

Were more lunar module LiOH cartridges just a spacewalk away?

The modularized equipment stowage assembly (MESA) was a drawer in the base of the lunar module descent stage which stored equipment and supplies. The modularized equipment stowage assembly (MESA) ...
DrSheldon's user avatar
  • 48k
24 votes
1 answer
4k views

Did Apollo 13 "barbecue roll" under the propulsion of the lunar module?

Apollo spacecraft were often put in a "barbecue roll" (officially called passive thermal control mode), which slowly rotated the spacecraft along its main axis. Without this maneuver, one side of the ...
DrSheldon's user avatar
  • 48k
4 votes
1 answer
155 views

Was LM1 of Apollo 5 equipped with additional sensors and telemetry for the umanned "fire in the hole" test?

The first unmanned test of the Lunar Module was done in mission Apollo 5 LM 1. The separation of the ascent stage from the descent stage was done during flight. Did they install additional sensors and ...
Uwe's user avatar
  • 49k
6 votes
1 answer
347 views

Had using the LEM's engines for a lunar abort "never been tried like this?"

From the 1995 film Apollo 13, GRUMMAN REP: I just want you to know the engines never been tried like this. That's all I'm trying to tell you. Is it true that Grumman had never considered such a ...
DrSheldon's user avatar
  • 48k
8 votes
2 answers
623 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 ...
venom's user avatar
  • 333
13 votes
1 answer
1k views

Could the Apollo Lunar Module be flown to a landing without the LEM Guidance Computer?

Inspired by answers to Could the lunar module have moved to a different spot? question but not talking about that specific relaunch scenario: Could the LEM stack (descent configuration) be flown ...
Organic Marble's user avatar
30 votes
4 answers
4k views

Could the lunar module have moved to a different spot?

Suppose Neil Armstrong had landed with plenty of spare fuel, only to decide it really wasn't a good spot after all. Could he have lifted back off and landed again, perhaps a couple of hundred feet ...
Mark Foskey's user avatar
7 votes
2 answers
425 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 ...
Russell Borogove's user avatar
16 votes
2 answers
2k 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 ...
Russell Borogove's user avatar
2 votes
1 answer
609 views

Why does the LM footpad "flutter" when undocking from the Command Module?

In footage of the LM undocking from the Command Module, the footpad looks like it was "fluttering": At first, I thought it was from the RCS thrusters but then I ...
Star Man's user avatar
  • 5,928
4 votes
2 answers
302 views

Does a full-scale Apollo lunar module mock-up exists that allows visitors to explore the inside?

The Lunar Module was an utterly amazing spacecraft. It's also one for which getting a feel for the inside is extremely difficult from photos$^*$. Has anyone made a full-scale mock up of the lunar ...
user2705196's user avatar
  • 1,307
11 votes
3 answers
1k 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 ...
Sergiy Lenzion's user avatar
10 votes
2 answers
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 ...
uhoh's user avatar
  • 149k
3 votes
2 answers
421 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 ...
Sergiy Lenzion's user avatar
9 votes
1 answer
228 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 ...
zephyr0110's user avatar
  • 2,901
2 votes
2 answers
629 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 ...
Star Man's user avatar
  • 5,928
16 votes
2 answers
6k views

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?
Uwe's user avatar
  • 49k
6 votes
1 answer
229 views

Did the LEM ever rise above the orbit of the CSM at any time

We all know that the LEM descended from the CSM to the moon's surface and then rose back again to dock with it. But there are some videos that show the CSM floating in the foreground with the moon's ...
A-Zone's user avatar
  • 69
27 votes
4 answers
8k views

Why is the Apollo LEM ladder so far from the ground?

In an answer to this question, the following photo was posted: (source: NASA Apollo 11 Image Library) This made me recall that the first thing Armstrong did after climbing down the ladder to the ...
Ludo's user avatar
  • 14.4k
33 votes
5 answers
7k views

Why were contact sensors put on three of the Lunar Module's four legs? Did they ever bend and stick out sideways?

In the video Brian Eno on Apollo starting at 08:37 there is Apollo-era movie footage of a lunar module taken from the command module as it prepares for descent ...
uhoh's user avatar
  • 149k
7 votes
3 answers
643 views

How much were the LMs maneuvered to their landing points?

The story of the Apollo 11 landing includes Armstrong having to fly the LM beyond a boulder field at the automatically targeted site. Was this essentially continuing along the same track the LM had ...
Anthony X's user avatar
  • 17.5k
13 votes
2 answers
3k views

How were the LM astronauts supported during the moon landing and ascent? What were the max G's on them during these phases?

I understand that the LM astronauts descent trajectory had them flying feet first in a standing position during the descent to the lunar surface and again on ascent. But it seems there must have been ...
PJNoes's user avatar
  • 235
14 votes
4 answers
7k views

How can electronics on board JWST survive the low operating temperature while it's difficult to survive lunar nights?

Compared to the temperatures encountered in lunar nights, the desired operating temperature of the James Webb Space Telescope is very low. Lunar nights are typically -170°C while the operating ...
karthikeyan's user avatar
  • 4,469
27 votes
5 answers
6k 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.
R S's user avatar
  • 373