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# Tag Info

191

This is the Apollo 11 photo designated AS11-40-5925, a popular shot with moon landing deniers. The camera is facing generally north-north-west. The sun is low in the sky, about 10º-15º above the horizon on the east. The silver pole in the upper right of the photograph is pretty much straight up, casting shadow in the expected direction. The landing leg in ...

17

Partial answer (everything but exactly when in the timeline it was done): The fuel capsule was installed at the launch pad "through a ten-inch access port in the spacecraft structure". The fabulous document ALSEP Flight System Familiarization Manual includes this info and much, much more. The only time given is "after the LM has been fueled". (page 4-5) ...

16

It's one of the VHF antennae. Locations shown here. 1st image from here: http://www.ninfinger.org/karld/My%20Space%20Museum/pjlmpics.htm 2nd image from here: https://www.hq.nasa.gov/alsj/a11/LM5Structures.gif This document https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20090015392.pdf shows that VHF was used for comm between the CM and LEM, and ...

12

Approximately, yes. The gross gravitational effects on the trajectories of the spacecraft and the other object will be the same. The force of gravity between two objects is proportional to the product of their masses; by $F = m a$, the acceleration of each object cancels out its own mass ( $a = \frac {F} {m}$ ) and so depends on the mass of the other object....

9

Cannot identify the specific model, but they would be ancestors of these that work by popping out under load or manual trip and push back in to reset/turn on. They are widely used in aviation because they are compact and relatively easy to operate by feel. They generally take very little force to pop out, since that is spring assisted. Because they ...

8

This paper by Dan Adamo states that their fate is unknown. Other Apollo Program hardware certainly accompanied some of the components cited here into interplanetary space. Unfortunately, there are no empirical data relating to these objects' trajectories. Likely the largest such undocumented disposed components are four spacecraft/LM adapter (...

7

Unsurprisingly, it worked exactly like it did in shuttle. To assure uniform flow, the capillary restrictors are coiled around a warm water-glycol line to increase the oxygen temperature. Page 2.7-3 The aforementioned oxygen supply capillary restrictors are wound around the line routed to the space radiators and relief valves. The other line is ...

7

I've been refining a general rocket launch simulation program over the last few years, modeling it on the work described here by Robert Braeunig. According to my current version of the simulation, it's possible to launch 134,000kg of payload (including fairing mass) to a 185 km x 200 km orbit at 28.5º inclination on the INT-21, in addition to the nearly-...

6

They worked like standard aircraft types. Pushed in = circuit closed Popped out = circuit opened The "knob" was made of non-conductive plastic (don't know the exact type) Circuit breakers, are thermal-mechanical in nature. Bimetallic elements, with one metal expanding more under heat than the other, pop the breaker open. This also enables them to ...

6

Both horizontal and lateral velocity could be displayed on the cross-pointer display. Based on the position of the Mode Select and Rate/Err Mon switches, the velocity displayed came from one of four (for lateral velocity) or one of three (for forward velocity) sources. Lateral Velocity: Rate / Err Mon switch in Rndz Radar position: Rendezvous Radar ...

5

I have not yet found the abort limit figure. According to Saturn V AS-507 "G" Mission Launch Vehicle Operational Flight Trajectory - September Launch Month (a trajectory planning document for Apollo 12), the peak Qɑ for a nominal flight would be between 18 and 22 kNº/m^2 (= kPaº):

4

The acceleration due to gravity will be identical regardless of mass, assuming the mass of your spacecraft is negligible compared to mass of the object you're orbiting. For example the Earths moon is large enough to effect the motion of the earth so it doesn't orbit the centre of the earth, but instead it orbits the shared centre of mass of the Earth and ...

4

(Partial answer) The LEM had ... ... four oxygen supplies : two, in the descent stage, provide oxygen during the descent and lunar- stay phases of the mission: two, in the ascent stage, during the ascent and rendezvous phases of the mission. The caution and warning limit values can tell us the range of pressures expected to be nominal. An ...

4

Using this page you can calculate how big a telescope must be to view any object at any distance: http://win98.altervista.org/telescopio.html Page also lists data for some known telescopes and some famous site, for example Hubble telescope and Apollo 11 landing ste: Hubble-Moon resolution (400000 km, 2400 mm telescope): 93 m Apollo Lunar Excursion Module ...

4

Looking at this photo https://en.m.wikipedia.org/wiki/File:Apollo_15_Engine_Bell.jpg It seems there is a local terrain elevation (a hill) right in the middle of LM final landing spot with engine bell resting on the surface (note also how the bell is damaged: they must have had a decent bump on touchdown). Having some horizontal velocity, they would approach ...

3

Partial answer to help bound the values: The SA-507 Flight Manual page 3-9 says the nominal meter indications shouldn't exceed 25% to 50% of the limit. With the max nominal numbers in the other answer of 20 kNº/m^2 that puts the limit somewhere between 40 - 80 kNº/m^2.

3

According to the Apollo 14 LM Timeline Book, the MODE SEL switch that selects the source for the pointers is set at two different points. At LANDING RADAR CHECKOUT, at mission time 106:30, the RATE ERR MON switch is set to LDG RDR/CMPTR and MODE SEL is set to LR, so the cross-pointers are controlled from the landing radar. Between 108:00 and 108:20, we ...

2

The four pieces of the SLA fairing would follow a similar path as the third stage S-IVB of the Saturn V. The SLA pieces were separated by explosive devices only, so their additional acceleration was very, very small. See apollomaniacs. After Wikipedia, the S-IVB stages of the missions 8 to 12 are in heliocentric orbits now and of the missions 13 to 17 were ...

2

What the other answers fail to mention is that the mass of your orbiting object actually cancels out. It does not matter. See these two equations: (1) F1 = F2 = G*m1*m2 / r^2 (2) F1 = m1 * a1 Where F is force, G is the universal gravitational constant, m is mass, and r is distance between centers of mass of the orbiting and orbited bodies in question. The ...

2

Based on @OrganicMarble's answer I did some further reading. @William-Rem's comment asks: Is that a quadrafilar antenna with... a ground plane?" and the answer appears to be yes; the four rods pointing radially below the quadrafilar "cloverleaf" are labeled as a ground plane in Figure 6. As @OrganicMarble already points out, the VHF antennas were used ...

2

From the Apollo Document NASA TN D-6724 APOLLO EXPERIENCE REPORT - LUNAR MODULE ENVIRONMENTAL CONTROL SUBSYSTEM a large descent-stage gaseous oxygen tank (approximately 48-pound capacity at 3000 psi) and two ascent-stage gaseous oxygen tanks (approximately 2.4-pound capacity each at 900 psi). A pressure regulator was used to reduce the high pressure ...

2

In theory, a VLBI (very long baseline interferometric) set of telescopes can provide the resolution you need. Basically, placing a few telescopes of reasonable aperture far apart from each other and relaying their images to a common collection system (the interferometer) will give you excellent high-spatial-frequency images. You will not get much of the ...

2

Here is what I have found: Apollo 4- Managed by the Smithsonian, is not on display there. May be on loan, can't figure out where. Apollo 17- On display at the Kansas Cosmosphere Apollo 15- Was recovered for sure, as y you mentioned. It seems like not as much effort was put forward to recovering these. Apollo 4 was probably recovered because it was the ...

1

Except for the Apollo 15 and 17 articles, it appears the Forward Heat Shields are resting at the bottom of the ocean. Somewhere. From Wikipedia: At 24,000 feet (7.3 km) the forward heat shield was jettisoned using four pressurized-gas compression springs. The drogue parachutes were then deployed, slowing the spacecraft to 125 miles per hour (201 ...

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