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The rover computer was an analog/digital hybrid system called the Signal Processor Unit (SPU). As explained in answers to this question How did astronauts navigate the Lunar Roving Vehicle (LRV) over the surface of the Moon? the inputs to the computer came from wheel pulse odometers and a directional gyro unit. Here is a block diagram of the system.
The ...
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The 18 rescue cases are detailed in the CMP Solo Book and they are all for the undocked phase of the mission after the LM undocks from the CSM in lunar orbit. In most cases the LM can not do or can't fully do the burns required to get back to the CSM in an emergency, so the CSM has to come and rescue it.
Here is the page with the list of rescue cases:
...
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The most familiar issue is that the Apollo 10 LM was still above its target weight by a couple of hundred pounds. A safe landing would have been physically possible, but not with the desired propellant margins. However, the lighter Apollo 11 LM had already been completed and delivered 4 months prior to the flight of Apollo 10 -- the production and assembly ...
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The thrust deflectors on the descent stage were added to Eagle when it was already stacked on the Saturn V after the flights of Apollo 9 and 10 showed that the exhaust from the downward-facing attitude thrusters were impinging on the structure. Also, not really as a result of the test flights, the ground contact probe on Eagle's forward footpad was removed ...
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indy91 posted an image copy of a page from Michael Collin's CMP Solo Book. The text contents of that image are
APOLLO 11 FLIGHT DATA FILE CMP SOLO BOOK
RESCUE INDEX
CASE 1 - PARTIAL DOI ( <25 FPS) (CSM ACTIVE)
CASE 2 - PARTIAL DOI (>25 FPS) (CSM ACTIVE)
CASE 3 - NO PDI1, +12 (LM ACTIVE)
CASE 4 - <60 NO PDI1, +12 (CSM ACTIVE)
CASE 5 - ≥60 NO PDI1, +...
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I have found two instances of a "selectover" from the Mission Operational Computer (MOC) to the Dynamic Standby Computer (DSC), one on Apollo 13 and one on Apollo 15.
Apollo 13:
The single episode of computer faults during this mission occurred
during the period of two computer, i. e., MOC/DSC operation, and there
was no interruption to mission ...
9
The Lunar Sounder was a radar experiment contained in the service module experiment bay during Apollo 17. The results were recorded on microfilm while in orbit around the moon, and the film cassette was retrieved with a spacewalk by the command module pilot (Ronald Evans) during the trip back to Earth:
The lunar sounder experiment, flown on the Apollo 17 ...
4
Converting between different frames of reference is pretty straight forward.
You subtract the velocities. That's it.
If you have the spacecraft's velocity relative to the Earth, you can just subtract the Moon's velocity relative to Earth. Then you have the spacecraft's velocity relative to the Moon.
In the case of a lunar transfer orbit, the spacecraft is ...
answered Oct 20 at 18:17
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3
You are unlikely to find this number (yes, I have looked), because that's not how the lunar module was designed or constructed.
Section 9.1.1.2 of the Apollo Program Summary Report describes the construction of the command module. The pressure vessel is a distinct layer that is constructed first. Then, a second phase of welding adds the longerons (the ...
3
Yes.
According to the official list of items left on the moon by Apollo, Apollo 15 left a
Microfilm roll containing Apollo 11 Manned Flight Awareness booklet
"Manned Flight Awareness" was a program designed to heighten employee sensitivity to the fact that real people were flying on the vehicles they worked on. It produced motivational posters ...
3
What was the normal function of the (coax?) crosshairs used during the Apollo 13 famous manual burn?
Generally, they used the optical alignment sight to align the spacecraft when docking. https://www.hq.nasa.gov/alsj/coas.htm
The film may be referring to the landing point designator, or LPD found in the commanders window.
Edit: Fixed my acronyms! I apologize for my incorrectness.
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Summary: There was no alternative to the launch escape system; it relied on redundancy and testing. But there were two ways to detach the LES.
There were two different mechanisms to separate the LES from the command module. During a normal flight, the frangible nuts connecting the legs of the LES to the CM would be detonated. During an emergency escape, ...
2
The CSAR (coherent synthetic aperture radar) did not use very high frequencies and short wavelengths like 3 GHz (0.1 m) or 30 GHz (0.01 m) allowing small narrow beam directional antennas.
Very low frequencies of 5 , 15 and 150 MHz and 60 , 20 and 2 m wavelength were used. These low frequencies were selected to image not only the lunar surface but also the ...
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While DrSheldon's answer is likely the most useful one, an upper limit of the materials forming the pressure wessel could be found by taking the mass of the LM ascent stage, and subtracting everything that isn't part of the pressure vessel.
Unfortunately, accurate mass data for the parts isn't easy to find.
The dry mass is either 4,700lb (2,130 kg) or 4,...
answered Oct 3 at 12:41
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While the overall scope is too broad, let me address the "low energy transfer" part.
Firstly, the idea of "gradually increasing apogee" doesn't save you any fuel. Chandrayaan-2 did that because of limited thrust. The only saving to be had here is picking an engine with a slightly lower mass.
Secondly, a "ballistic capture", as ...
answered Oct 20 at 8:36
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1
This is a late answer; a closely related question was recently closed as a duplicate of this.
Does mass of orbiting body affect the orbital speed?
tl;dr: Yes it always does, about half as much. If it's small, like one millionth the mass of the primary, the change in speed is one half of one millionth for example. In the extreme case when the two masses are ...
1
This is a late answer; a closely related question was recently closed as a duplicate of this.
Does trajectory of an object orbiting a planet depend on the object's mass?
Yes, it does.
Several of the answers correctly invoke the principle of the universality of free fall, which dictates that the acceleration from the perspective of an inertial frame of ...
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