Radiation

[benparry]

after reading this very short thread (again sorry for that) it seems to me (and compared to everybody including Tim I am very inexperienced and uneducated) there are a few bits which tangle him. firstly the trajectory through the VAB. I believe this region to be a 3D donut shaped region in space. the TLI were inclined about 30 degrees which allowed them to bypass the inner more dangerous regions. then for the GCR. Tim has tried to compare data on Apollo with other more recent missions which had both different vehicles, were unmanned, and occurred at different solar cycles. finally the neutron radiation which Tim claims is increased by 35 percent in orbit. again this figure is derived from a more recent mission with a higher solar cycle. is what I have written here basically the crux of all this

These are the salient points of the argument, but the real issue being that the problem is very complicated and cannot be distilled into convenient back of the envelope calculations and extrapolating scientific research and mapping that research on to the mission data.

The main thrust here has shown Tim is illiterate in the fields at every turn, and invokes literature that refutes his own claims. For him to ask for a reference pertaining to the VAB composition shows he's behind the curve ball. He shouldn't even be in the same 'room' as people here. We've hardly scratched the surface of the problem he's trying to boil into a few bones.

yeah over simplification. I suppose also the missions being compared are radiation received by the craft and radiation received by the astranauts. 2 different things am I right. can I just ask 1 final question before I hit the hay. how does one calculate that 30 degrees (the launch angle) would be enough to miss the bad bits of the belts. does it depend where the earth is in its cycle or ....

[Luke Pemberton]

yeah over simplification. I suppose also the missions being compared are radiation received by the craft and radiation received by the astranauts. 2 different things am I right. can I just ask 1 final question before I hit the hay. how does one calculate that 30 degrees (the launch angle) would be enough to miss the bad bits of the belts. does it depend where the earth is in its cycle or ....

I defer to an expert on this, or an Apollo enthusiast. I think the 30 degrees was a little more than 'missing' the 'bad bits' - if I recall. It achieved other mission criteria/objectives.

Jay?

[timfinch]

I am so glad you pointed out that little tidbit and I didn't.  It might have seemed a bit self serving if I had.  Let us assume both you and NASA are entirely correct and it was a mere 13 rads accumulated over the VAB  transit.  Could you please explain to all your fans and friends and the audience how you can squeeze that into a mission dosage of .22 mgy/day.  I am going to ge a bag of popcorn because I love a good magics show.

Ignoring the point of my rebuke is classic troll behavior.  Now deal with the point, and if you can't figure out what that is, you really have no business even walking outside, much less trying to discuss anything here.

So now you want me to believe that the Apollo had some form of shielding other than superstructure and equipment and and this space age shielding while highly effective to VAB proton and electron fluxes is permeable to GCR and SPE and neutron flux.  Right..  You expect me to believe that the shielding on the Apollo 11 craft was superior to the orion craft that launched 50 years later and probed the heart of the VAB?  Is that what you want me to believe.  Really?

[Luke Pemberton]

So now you want me to believe that the Apollo had some form of shielding other than superstructure and equipment and and this space age shielding while highly effective to VAB proton and electron fluxes is permeable to GCR and SPE and neutron flux.

Strawman. It was explained an early point that we agree that the CM offered little protection against GCR. We agree that the CM would only attenuate SPEs, and in the event of a very extreme SPE, it is probable the astronauts would have been incapacitated.

There were no SPEs during the Apollo flights. So all we have to deal with is the GCR and VABs.

Now, what electron flux in the outer VAB and how is this differentiated across electron energies?
How would the craft, rated at 8 g cm^-2, perform attenuating these electrons - can you perform the integrated flux calculation? Yes or no?

[timfinch]

So now you want me to believe that the Apollo had some form of shielding other than superstructure and equipment and and this space age shielding while highly effective to VAB proton and electron fluxes is permeable to GCR and SPE and neutron flux.

Strawman. It was explained an early point that we agree that the CM offered little protection against GCR. We agree that the CM would only attenuate SPEs, and in a very extreme SPE would have left the astronauts  incapacitated.

There were no SPEs during the Apollo flights. So all we have to deal with is the GCR and VABs.

Now, what electron flux in the outer VAB and how is this differentiated across electron energies?
How would the craft, rated at 8 g cm^-2 perform attenuating these electrons - can you perform the integrated flux calculation? Yes or no?

They engaged proton shields and could disregard them in their entirety.  I like it.  You provide be the radiation shielding thickness of the apollo( she had zero) and I will due the exposure calculation for you.  I am an ex Navy nuke remember.  I contend the Apollo had no radiation shielding so I need something definitive to prove otherwise.  I want to make this work for you.  I must admit I do love watching you wriggle on that hook firmly implanted in your gullet

[MBDK]

I am so glad you pointed out that little tidbit and I didn't.  It might have seemed a bit self serving if I had.  Let us assume both you and NASA are entirely correct and it was a mere 13 rads accumulated over the VAB  transit.  Could you please explain to all your fans and friends and the audience how you can squeeze that into a mission dosage of .22 mgy/day.  I am going to ge a bag of popcorn because I love a good magics show.

Ignoring the point of my rebuke is classic troll behavior.  Now deal with the point, and if you can't figure out what that is, you really have no business even walking outside, much less trying to discuss anything here.

So now you want me to believe that the Apollo had some form of shielding other than superstructure and equipment and and this space age shielding while highly effective to VAB proton and electron fluxes is permeable to GCR and SPE and neutron flux.  Right..  You expect me to believe that the shielding on the Apollo 11 craft was superior to the orion craft that launched 50 years later and probed the heart of the VAB?  Is that what you want me to believe.  Really?

I don't care WHAT you believe, I am asking you what you have done to calculate the dose to the astronauts themselves.  So far, all you have shown is incredulity, but no indication of understanding.  If that is all you can bring to the table, your entire argument is pure conjecture, void of scientific *ahem* acumen.

Also, were you able to examine the dose graph I mentioned?  Have you reached any meaningful understanding of it?

[benparry]

Tim you sound ridiculous this has been gone over so many times.

[MBDK]

I am an ex Navy nuke remember.

And remember that I know just how little that relates to this discussion.  You were given the same radiological training as is given to a bilge cleaner who must perform their duties in a radiation area.

[Luke Pemberton]

You provide be the radiation shielding thickness of the apollo( she had zero) and I will due the exposure calculation for you.

Certainly. The hull was rated at 8 g cm^-2. Now perform the exposure calculation for electrons in the outer belts.

[Luke Pemberton]

I am an ex Navy nuke remember.

OK, I have a pure alpha source, no beta or gamma. What materials would I need to ensure that alpha particles were completely absorbed, but reach a trade off that my protection system was light weight as possible?

[gillianren]

Tim.  Why is the solution not simply that you don't understand?

[timfinch]

You provide be the radiation shielding thickness of the apollo( she had zero) and I will due the exposure calculation for you.

Certainly. The hull was rated at 8 g cm^-2. Now perform the exposure calculation for electrons in the outer belts.

Show me.  I reject that as false and purely speculative.

[Luke Pemberton]

Show me.  I reject that as false and purely speculative.

Erik Seedhouse - Space Radiation and Astronaut Safety (attached image of a footnote).

So now you have been provided with the surface density, compute the the exposure in the outer van Allen belts. That's what you said you'd do? Right?

You provide be the radiation shielding thickness of the apollo (she had zero) and I will due the exposure calculation for you.

[Valis]

Averaging out the Crater Data to a daily average is proving a bit challenging.  Has anyone else accomplished this or does anyone have an algorithm to efficiently accomplish this?

That's trivial with any scripting. If you don't know how to do that, take in Excel in another column the sum of the day's hourly values divided by 24 (=SUM(B1:B24)/24 for example), and copy-paste that for every day in steps of 24.

There is almost 70 thousand entries and I was actually looking for something a bit more elegant but thank you for the attempt.  If you find this type of repetitive work thrilling then I will patiently wait to savor the fruits of your efforts.

I see that the thread has moved on from this, but anyway, as said, it's a trivial exercise if you take the time to learn to use the proper tools of the trade. Excel really isn't what you'll want to use for any larger datasets, though if that's all you can use, I'd guess plotting a rolling average with an interval of 24 and ignoring the extra points it produces would work.

[Jason Thompson]

So now you want me to believe that the Apollo had some form of shielding other than superstructure and equipment

No, the shielding is provided by the superstructure and equipment. The composition of the command module is not hard to come by in technical documentation. Can you do the calculation yourself to show that those layers of aluminium, steel, phenolic resin, kapton, plastics and so on are actually 'zero' shielding?

and and this space age shielding while highly effective to VAB proton and electron fluxes is permeable to GCR and SPE and neutron flux.

Yes, because they have different energies. This is the whole point of this entire discussion. I honestly cannot believe you don't actually get this at this point.

You expect me to believe that the shielding on the Apollo 11 craft was superior to the orion craft that launched 50 years later and probed the heart of the VAB?

Again no. The Apollo shielding was adequate for the part of the belts it actually passed through. You have been told and shown countless times how it avoided the 'heart' of the belts. Again, this is looking like wilful obtuseness designed to provoke us.