# Tag Info

## New answers tagged apollo-program

4

Why would there be? The Apollo mission goal was to examine the Moon, not take pretty pictures of Earth. The seminal Earth image was taken by Apollo 8, this turned out to be an important image. But subsequent repeats wouldn't add much value to this. The astronauts had freedom in what they took pictures of, but they had a limited amount of photo magazines ...

0

An ALSEP document quoted in this answer https://space.stackexchange.com/a/39611/6944 gives the fuel capsule temperature as 1200 deg F. Doesn't give the radiator fin temp though.

3

I've found a couple of test reports on other RTGs designed for space. First, from A report on RTGs for Pluto and other missions post 2006: The RTGs (Qualification Unit and flight units) were assembled in the Inert Atmosphere Assembly Chamber (IAAC) at Mound (except for F-8 which was assembled at INL). Mound and INL performed initial RTG functional ...

5

Moon Loping is a form of legged lunar locomotion performed by humans on the natural Earth satellite (the Moon) where the human propels itself through a space above the lunar surface along a ballistic trajectory with relatively long duration of the floating phase. Lunar gaits page gives the following description: Most of the astronauts on the later ...

5

If such a thing happened, it would most likely have been during the approach and rendezvous of the LM ascent stage with the CM, as Conrad and Bean were returning from the lunar surface. The most challenging part of the mission would be behind them and there would be a little window of time where they could maneuver around on the RCS thrusters without any ...

5

Here’s a detailed description of the biomedical instrumentation system: https://history.nasa.gov/SP-368/s6ch3.htm This included heart and respiration monitors. Presumably, sleeping was inferred from slow and steady heartbeat and breathing. I don’t believe ISS astronauts wear bio monitors on a regular basis.

0

Community Wiki answer: I've incorporated "translations" from existing comments on the question; feel free to edit/improve: 1. RTCC SS1 and SS2 RTCC = real time computer complex; the Mission Control computer system 2. MSFN free flight trajectory MSFN = Manned Space Flight Network, the network of ground tracking stations. 3. Langley model Langley would ...

36

All six successful landings were done manually, with the commander taking the controls at about 500 feet altitude. It was possible for the computer to complete the landing automatically, and Jim Lovell claimed that he was going to attempt that mode on Apollo 13, but all the commanders felt more comfortable in manual control in the final phase of landing. It'...

12

The restrictions you are quoting only apply to the LGC, the computer in the Lunar Module. The Command Module Computer does not have these restrictions (compare the section about the Coasting Integration Routine you quote with the same passage from the document about the CMC: https://www.ibiblio.org/apollo/Documents/R-577-Colossus2-Martin-5.2.pdf). The CMC ...

5

I found these three active links on Sound Cloud: Apollo Caution and Warning System- Master Alarm https://soundcloud.com/stefan-kramperth/05-nasa-apollo-caution-and Apollo Command Module Master Alarm https://soundcloud.com/lambertstudios/apollo-command-module-master-alarm Apollo 13 (1995) Master Alarm Sound Effect https://soundcloud.com/iam-agena/apollo-13-...

25

Reaction control system jet interactions with a vehicle's aerodynamic flowfield can be counterintuitive. Here's a capsule simulation results graphic showing similar spreading effects below the jet as well as laterally (from the first link below). This paper states in reference to Apollo: Interference heating in the case of the yaw and roll jets covered ...

2

Yes! The good folks at AGI (Makers of STK) simulated the entire Apollo 11 trajectory in STK: "Based on original NASA documentation, our engineers have built a high-fidelity, eight-day digital mission in Systems Tool Kit (STK). They modeled precise trajectories using STK Astrogator" The web site has tutorials on how to do some of the simulation using STK/...

3

There were plans in place to deal with a large scale CME. These storms would not have been instantly deadly, but could have caused a serious case of acute radiation syndrome. The plan was if such an event happened was to get home ASAP, and treat the ARS on Earth. There is an article from NASA talking a bit about this. If there was a storm threatening, they ...

2

According to Wikipedia, "Whole body doses of more than 1,000 rad are almost invariably fatal" "A dose of 100 to 200 rad delivered to the entire body in less than a day may cause acute radiation syndrome (ARS), but is usually not fatal" https://en.wikipedia.org/wiki/Rad_(unit) According to Apollo 11 Lunar Surface Journal, https://history.nasa.gov/alsj/a11/...

21

To answer the question literally: you'd be looking for NASA Apollo Trajectory (NAT) data files. The report Apollo Mission 11, Trajectory Reconstruction and Postflight Analysis Volume 1 (PDF) provides a summary for Apollo 11 and mentions that the raw NAT data is available in Volume 2 of the report. I have yet to find Volume 2 though, perhaps because The ...

18

Not exactly "over the top" (still through the outer portion of the belts), but yes, it appears so, according to this source. There are simplified trajectory plots shown in the link. Also this source quotes a letter from Van Allen himself: ...the outbound and inbound trajectories of the Apollo spacecraft cut through the outer portions of the inner belt ...

9

The Apollo attitude control system starts from a known orientation established by taking star sightings, then uses gyroscopes to track the change in orientation over time. The problem with gimbal lock is that the system can no longer distinguish the axes of rotation properly, so can't tell how the orientation is changing. The remedy for gimbal lock is just ...

7

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 ...

10

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 ...

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 ...

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 ...

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

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 (...

3

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

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 ...

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 ...

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 ...

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 ...

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 ...

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 ...

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 ...

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 ...

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