AE-8/AP-8 Questions

[Bob B.]

Outstanding work, Bob. I can't see any major problems at all, but if I go through it again I'll probably find some very minor nits.

Thanks so much for doing this.

Thanks and you're welcomed.  I'm still finding my own nits and have already made a few minor edits.

Here's another source of shielding that might be worth considering: the propellants (MMH and N2O4) for the CM reaction control system.

I the propellant is included in what I refer to as "secondary shielding" since my calculation of secondary shielding is based on the total CM mass (which includes the propellant mass).  I didn't get real specific about all that is included in secondary shielding because I'm largely ignoring it in my calculations. Since the hull by itself does such an effective job, I didn't find it necessary to write much about secondary shielding.  However, I have changed the description from "equipment, instrument panels, etc." to "equipment, instrument panels, propellant tanks, etc."

[ka9q]

Here's an interesting thought experiment. Let's say you're a health physicist supporting an Apollo mission when it's unexpectedly hit by a severe CME. An abort is not viable. How could the astronauts best protect themselves until it's over?

We'll assume they're in the CSM.

The safest place would seem to be underneath the couches, as close to the protection of the SM as possible. If the radiation is directional, you'd reorient the SM. (The particles follow the sun's interplanetary magnetic field so you wouldn't necessarily put it directly between the astronauts and the sun.)

You'd also want to cover yourself with as much shielding as possible to protect against radiation coming through the sides of the CM, probably by strapping just about anything movable to the tops of the couches: food, trash, LiOH canisters, other supplies, etc.  If the LM is attached, the PLSSes would probably make good shields, especially if their tanks are full. Water is especially good shielding, so loading it (or urine!) into bags seems like a good idea.

Anything else?

[JayUtah]

This contingency was planned for.  Anisotropic flux was indeed mitigated by orienting the CSM stack to place the bulk of the SM in the direction of highest flux.  The crew carried a portable radiation detector/counter that they were supposed to use to find the most shielded place in the CM cabin.

[Bob B.]

This contingency was planned for.  Anisotropic flux was indeed mitigated by orienting the CSM stack to place the bulk of the SM in the direction of highest flux.  The crew carried a portable radiation detector/counter that they were supposed to use to find the most shielded place in the CM cabin.

My article briefly mentions this in the section "Radiation Plan for Apollo."

[Allan F]

On the outgoing journey, the LM would shield quite well from the front, the SM from the back. That leaves the sides. So hide in the bottom compartment, stacking whatever loose supplies around the side?