Author Topic: Radiation  (Read 626761 times)

Offline Ranb

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Re: Radiation
« Reply #75 on: March 24, 2018, 06:54:47 PM »
I was a Navy Nuke from 1979 to 1991.  Unless you attended Nuke School in the late seventies or early eighties then you have no idea what we were taught.  Maybe you should ask someone.
Nuclear navy from 1983-2003.  I have a very good idea of what you were taught.  I also know it was junior college level at best and the nuclear physics portion of the school was not advanced at all.  Sure I could calculate the required fuel load of an S3G core 3 and describe the neutron life cycle, but it really did little to improve my understanding of the radiation environment that exists in space.  Listing your sources is a much better way of convincing anyone here than saying that you were a nuclear electrician on a sub who operated the throttles, brought on shore power and flipped switches on the EPCP.
« Last Edit: March 24, 2018, 06:58:33 PM by Ranb »

Offline Ranb

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Re: Radiation
« Reply #76 on: March 24, 2018, 06:57:43 PM »
I actually read it in one of the threads here.  I have searched for corroboration but as yet I have been unable to confirm it.
People here who believe manned lunar missions were possible in the 60's sometimes disagree and even make mistakes.  I caught Jay in a mistake on a matter of radiation in space and am still waiting for my t-shirt.  :)

What most of the people here have in common is that they're able to list their sources of information.

Offline timfinch

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Re: Radiation
« Reply #77 on: March 24, 2018, 06:58:48 PM »
I was an EWS for 7 of those years, supervising ELT's now go figure.
« Last Edit: March 24, 2018, 07:02:34 PM by timfinch »

Offline Ranb

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Re: Radiation
« Reply #78 on: March 24, 2018, 07:09:36 PM »
I was an EWS for 7 of those years, supervising ELT's now go figure.
I was also qualified as an Engineering Watch Supervisor, doesn't mean I was telling the ET's or EM's how to accomplish their maintenance or stand their watch.

I have a background in radiation work....
I figure that your background in radiation work was mostly limited to wearing a TLD and SRPD during maintenance for lighting or other electrical repair work in the reactor compartment.  Chances are your radiation survey experience with an AN/PDR-27 was limited to a sign-off on your qualification card and your contamination survey experience ended with the completion of your 2-3 minute whole body frisk after each reactor compartment exit.

Every EM I knew on a boat was far too busy keeping their gear functioning to bother with the duties and responsibilities of Reactor Laboratory (ELT's) Division.
« Last Edit: March 24, 2018, 07:15:13 PM by Ranb »

Offline timfinch

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Re: Radiation
« Reply #79 on: March 24, 2018, 07:24:31 PM »
My young padawan, you never knew me.  What has my credentials have to do with the information I provided or the assertion I made?  Prove me wrong or remain silent on the subject.  I am not impressed that you are not impressed.

Offline Ranb

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Re: Radiation
« Reply #80 on: March 24, 2018, 07:43:03 PM »
My young padawan, you never knew me.
I'm not your apprentice and I've no reason to believe that you're the master of anyone.

What has my credentials have to do with the information I provided or the assertion I made?
You have stated that your background in nuclear work (limited to NEC 3364?) is somehow relevant to this discussion.  I say it is completely irrelevant based on the details you have provided.

  Prove me wrong or remain silent on the subject.  I am not impressed that you are not impressed.
You told us of your background in nuclear power as if it was something credible upon which to support your claims.  I say based upon my similar but more extensive experience in radiological controls that your naval work history is not very meaningful when it comes to space medicine.

Please tell us more about where you got your data from.

Offline JayUtah

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Re: Radiation
« Reply #81 on: March 24, 2018, 08:01:59 PM »
My young padawan, you never knew me.
Your argument requires us to, since it's based on your expert judgment.

Quote
What has my credentials have to do with the information I provided or the assertion I made?

Because you are the one interpreting the data to indicate that the radiation metrics for Apollo are wrong, and suspiciously so.  That requires you to substantiate the expertise behind that judgment.  You also need to explain why your judgment is correct, while those with similar and superior expertise seem to have reached an entirely different conclusion.  This is not a trivial point.  You are claiming that anyone with nuclear electrician training in the Navy, or its equivalent, should be able to detect that Apollo radiation reports are wrong.  This would comprise a great many people.  You are not even the first to raise the radiation argument.  Part of your claim therefore needs to explain why all these similarly qualified people are wallowing in error and you seem to be one of the few who have found the "truth."

All you have given us is your judgment -- your opinion.  That's not really enough, given the whole landscape of evidence.

Quote
Prove me wrong or remain silent on the subject.

No, you still have a burden to prove your concerns are valid.
« Last Edit: March 24, 2018, 08:09:50 PM by JayUtah »
"Facts are stubborn things." --John Adams

Offline timfinch

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Re: Radiation
« Reply #82 on: March 24, 2018, 08:22:16 PM »
I have provided the documents to justify my position.  I can lead you to the fountain of knowledge but I cannot make you drink.  If you have Information contrary to the information I have provided I would love to see it.
« Last Edit: March 24, 2018, 08:31:11 PM by timfinch »

Offline timfinch

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Re: Radiation
« Reply #83 on: March 24, 2018, 08:27:23 PM »
I didn't realize that I needed a doctorate to have an opinion.
« Last Edit: March 24, 2018, 08:30:35 PM by timfinch »

Offline Ranb

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Re: Radiation
« Reply #84 on: March 24, 2018, 09:33:40 PM »
I have provided the documents to justify my position.  I can lead you to the fountain of knowledge but I cannot make you drink.  If you have Information contrary to the information I have provided I would love to see it.
You provided information contrary to your claims.

You speculated about a radiation level in post #45 then claimed that Apollo exposure did not match your expectations in #52.

In post #55 you linked to some data then went on to call this data evidence of similar exposure rates between low Earth orbit missions and those that went to the moon.  The average daily exposure rate for those Apollo missions that stayed in Earth orbit was .16 mGy, those that went to the moon averaged .50mGy.  Only by including Skylab which orbited about about 270 miles vs the early Apollo missions and ASTP which orbited lower at about 120 miles do we get an average daily dose rate approaching the lunar missions.

I didn't realize that I needed a doctorate to have an opinion.
Of course not.  But claiming a background of USN nuclear trained electrician does nothing to support your space medicine knowledge claims.  You had more to show us, where is it?

I rarely post on the forum; less than twice a month on average.  I've learned a ton by just lurking here.  So can you.

« Last Edit: March 24, 2018, 09:43:32 PM by Ranb »

Offline bknight

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Re: Radiation
« Reply #85 on: March 24, 2018, 09:48:54 PM »
The only claim I make is the radiation exposure of the Apollo lunar missions do not coincide with expected values using empirical data from the 21st century.  That is the extent of my claim.

You do realize that the data of the Mars mission was determined with little radiation protection whereas the Apollo capsule were layered with low density material and stainless steel.  Both are good insulators to radiation so the rates should be lower than those derived by Curiosity mission.

In a word, No.  You should recheck your notes on this as I believe you are completely wrong.
Cite where the detection panels were in cased with attenuation.
Truth needs no defense.  Nobody can take those footsteps I made on the surface of the moon away from me.
Eugene Cernan

Offline timfinch

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Re: Radiation
« Reply #86 on: March 24, 2018, 10:22:00 PM »
I have provided the documents to justify my position.  I can lead you to the fountain of knowledge but I cannot make you drink.  If you have Information contrary to the information I have provided I would love to see it.
You provided information contrary to your claims.

You speculated about a radiation level in post #45 then claimed that Apollo exposure did not match your expectations in #52.

In post #55 you linked to some data then went on to call this data evidence of similar exposure rates between low Earth orbit missions and those that went to the moon.  The average daily exposure rate for those Apollo missions that stayed in Earth orbit was .16 mGy, those that went to the moon averaged .50mGy.  Only by including Skylab which orbited about about 270 miles vs the early Apollo missions and ASTP which orbited lower at about 120 miles do we get an average daily dose rate approaching the lunar missions.

I didn't realize that I needed a doctorate to have an opinion.
Of course not.  But claiming a background of USN nuclear trained electrician does nothing to support your space medicine knowledge claims.  You had more to show us, where is it?

I rarely post on the forum; less than twice a month on average.  I've learned a ton by just lurking here.  So can you.
being a trained Nuclear Radiation worker establishes that I have more than a layman's understanding of the hazards of radiation exposure , nothing more.  I don't claim a specialized knowledge of space radiation biology or astrophysics.  I claim that I understand the basic principles involved.  Lurk on if you have nothing to contribute.

Offline timfinch

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Re: Radiation
« Reply #87 on: March 24, 2018, 10:29:27 PM »
The only claim I make is the radiation exposure of the Apollo lunar missions do not coincide with expected values using empirical data from the 21st century.  That is the extent of my claim.

You do realize that the data of the Mars mission was determined with little radiation protection whereas the Apollo capsule were layered with low density material and stainless steel.  Both are good insulators to radiation so the rates should be lower than those derived by Curiosity mission.

In a word, No.  You should recheck your notes on this as I believe you are completely wrong.
Cite where the detection panels were in cased with attenuation.

the potential radiation hazard for astronauts
(Zeitlin et al. 2013). Because of the shielding of the spacecraft
and internal structures, RAD measured a mix of primary and
secondary particles. The latter are produced by primary particles
via nuclear or electromagnetic interactions as they traverse the
spacecraft. A simplified shielding model of the spacecraft developed
at JPL has been be used to calculate the shielding distribution
as seen by RAD, which is mounted to the top deck of the
rover (Zeitlin et al. 2013). Shielding around the RAD instrument
during cruise was complex: most of the solid angle was lightly
shielded with a column density smaller than 10 g/cm2
, while the
rest was broadly distributed over a range of depths up to about
100 g/cm2
https://arxiv.org/pdf/1503.06631.pdf

Offline timfinch

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Re: Radiation
« Reply #88 on: March 24, 2018, 10:31:55 PM »
It is not as if the Apollo crafts has any shielding capable of attenuating the high energy protons of GCR so what is your point?

Offline JayUtah

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Re: Radiation
« Reply #89 on: March 24, 2018, 10:38:49 PM »
It is not as if the Apollo crafts has any shielding capable of attenuating the high energy protons of GCR so what is your point?

What was the GCR flux at 10 MeV and higher?
"Facts are stubborn things." --John Adams