Author Topic: Radiation  (Read 616525 times)

Offline JayUtah

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Re: Radiation
« Reply #90 on: March 24, 2018, 10:51:41 PM »
being a trained Nuclear Radiation worker establishes that I have more than a layman's understanding of the hazards of radiation exposure , nothing more.

Your argument involves expert judgment on data pertaining to astrophysics and design for space.  When asked to substantiate that expertise, you cited your training and experience in the Navy.  Now you're trying to walk that back and say that's not the basis of your expert judgment.  Which is it?  Either you don't have any relevant expertise, in which case there's a greater chance that your judgment -- contradicting that of people who's backgrounds are not in question -- is in error.  Or you do have relevant expertise, and you haven't disclosed it yet.

It seems you've been trained to safely operate and maintained equipment designed by others for a specific purpose in a specific environment that has almost nothing to do with Apollo or manned spaceflight.  If you concede that this training does not qualify you in astrophysics or space engineering or space medicine, that's a proper concession.  However it still leaves your argument as little more than baseless judgment.

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I don't claim a specialized knowledge of space radiation biology or astrophysics.

Do you agree that proper knowledge of those subjects is necessary to drawing correct conclusions about how spacecraft work and interact with their environment?  Would you agree that evaluating whether some spacecraft design is appropriate to some particular environment requires considerable knowledge in those areas?

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I claim that I understand the basic principles involved.

Can you explain why people with a greater knowledge than "basic principles" disagree with your conclusion?  Would you agree that "basic principles" as taught to technicians may not include important principles that would be more generally known among those who were experienced in the relevant design disciplines, or the scientific and research disciplines?  Is it reasonable to suppose that this greater and broader knowledge -- far above ordinary "basic principles" -- provides a more accurate basis for judgment regarding the validity of Apollo?
« Last Edit: March 24, 2018, 11:07:45 PM by JayUtah »
"Facts are stubborn things." --John Adams

Offline timfinch

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Re: Radiation
« Reply #91 on: March 24, 2018, 11:10:18 PM »
In deep space?

Offline timfinch

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Re: Radiation
« Reply #92 on: March 24, 2018, 11:14:07 PM »
being a trained Nuclear Radiation worker establishes that I have more than a layman's understanding of the hazards of radiation exposure , nothing more.

Your argument involves expert judgment on data pertaining to astrophysics and design for space.  When asked to substantiate that expertise, you cited your training and experience in the Navy.  Now you're trying to walk that back and say that's not the basis of your expert judgment.  Which is it?  Either you don't have any relevant expertise, in which case there's a greater chance that your judgment -- contradicting that of people who's backgrounds are not in question -- is in error.  Or you do have relevant expertise, and you haven't disclosed it yet.

It seems you've been trained to safely operate and maintained equipment designed by others for a specific purpose in a specific environment that has almost nothing to do with Apollo or manned spaceflight.  If you concede that this training does not qualify you in astrophysics or space engineering or space medicine, that's a proper concession.  However it still leaves your argument as little more than baseless judgment.

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I don't claim a specialized knowledge of space radiation biology or astrophysics.

Do you agree that proper knowledge of those subjects is necessary to drawing correct conclusions about how spacecraft work and interact with their environment?  Would you agree that evaluating whether some spacecraft design is appropriate to some particular environment requires considerable knowledge in those areas?

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I claim that I understand the basic principles involved.

Can you explain why people with a greater knowledge than "basic principles" disagree with your conclusion?  Would you agree that "basic principles" as taught to technicians may not include important principles that would be more generally known among those who were experienced in the relevant design disciplines, or the scientific and research disciplines?  Is it reasonable to suppose that this greater and broader knowledge -- far above ordinary "basic principles" -- provides a more accurate basis for judgment regarding the validity of Apollo?
If the people in question perpetrated a fabrication to conceal the fact that were incapable of delivering on a trillion dollar promise then it seems to me they would have a vested interest in disseminating fabrications and falsehoods but what do I know.  I am just a layman.

Offline timfinch

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Re: Radiation
« Reply #93 on: March 24, 2018, 11:16:54 PM »
Do you think the Wright Brothers wielded similar questions about the experise of highly trained engineers who thought manned flight was impossible?

Offline JayUtah

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Re: Radiation
« Reply #94 on: March 24, 2018, 11:17:41 PM »
In deep space?

You claimed the Apollo spacecraft were not shielded against GCR.  You insinuate that this is a problem.  To assess your judgment on that point, we will need you to supply the relevant data from appropriate sources that you used in reaching that judgment as well as a discussion of the rationale you applied to the data to arrive at that opinion.  GCR flux at thermal energies is one of several data that apply.
"Facts are stubborn things." --John Adams

Offline JayUtah

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Re: Radiation
« Reply #95 on: March 24, 2018, 11:22:00 PM »
If the people in question perpetrated a fabrication to conceal the fact that were incapable of delivering on a trillion dollar promise then it seems to me they would have a vested interest in disseminating fabrications and falsehoods.

Let me get this straight.  You're accusing the entire astrophysics and aerospace engineering community the world over -- including those not sympathetic to the United States -- of concealing the "fact" of Apollo's impossibility?

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...but what do I know.  I am just a layman.

Indeed you are, which is why we're questioning the basis of your judgment.  Nothing that you wrote addresses those concerns.  Given your broad, sweeping accusations above, isn't it more parsimonious to believe you simply are unfamiliar with the relevant fields and are therefore drawing simplistic conclusions?
"Facts are stubborn things." --John Adams

Offline timfinch

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Offline timfinch

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Re: Radiation
« Reply #97 on: March 24, 2018, 11:26:22 PM »
If the people in question perpetrated a fabrication to conceal the fact that were incapable of delivering on a trillion dollar promise then it seems to me they would have a vested interest in disseminating fabrications and falsehoods.

Let me get this straight.  You're accusing the entire astrophysics and aerospace engineering community the world over -- including those not sympathetic to the United States -- of concealing the "fact" of Apollo's impossibility?

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...but what do I know.  I am just a layman.

Indeed you are, which is why we're questioning the basis of your judgment.  Nothing that you wrote addresses those concerns.  Given your broad, sweeping accusations above, isn't it more parsimonious to believe you simply are unfamiliar with the relevant fields and are therefore drawing simplistic conclusions?
Why bring my character, intelligence and technical competence into question?  Simply disprove the assertion and be on your way.  This should not not be difficult because I obviously lack the the knowledge or competence to understand the complexities involved.  I have stated that current data indicates the apollo data is unrealistic.  Prove me wrong.

Offline timfinch

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Re: Radiation
« Reply #98 on: March 24, 2018, 11:30:16 PM »
https://www.ncbi.nlm.nih.gov/pubmed/12056428

This article speaks of shielding of  shielding up to 80 g/cm2 and 25 g/cm2 and correct me if I am wrong but the apollo had no radiation shielding at all and relied on heat shielding, equipment and superstructure to arrive at its estimate 10 g/cm2 shielding.
« Last Edit: March 24, 2018, 11:39:32 PM by timfinch »

Offline JayUtah

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Re: Radiation
« Reply #99 on: March 24, 2018, 11:32:19 PM »
Do you think the Wright Brothers wielded similar questions about the experise of highly trained engineers who thought manned flight was impossible?

Apples and oranges.

The scientific community in the late 1800s was indeed divided over whether powered flight was possible.  However, aside from a few bombastic quotes that have acquired ironic attention subsequently, there were quite a few fully qualified scientists and physicists -- among them Samuel Pierpont Langley -- who not only believed powered flight was possible but were actively working to achieve it.  A few assessments were based on various elementary texts in aerodynamics which the Wrights realized were in error.  In contrast there was not nearly the degree of skepticism in the relevant scientific community that a manned Moon landing was possible.  Everyone agreed it could be done, but not necessarily by the end of the decade.  The nature of engineering expertise in 1960 was not the same as it was in 1900.

The Wrights, faced with those certain errors in the prevailing wisdom, embarked on their own empirical research to correct the science.  They naturally kept these secret since they hoped to profit from patenting their invention.  But when the patent was secured, the details of their work was revealed.  They were able to demonstrate their correctness in the face of a certain amount of prevailing wisdom not only in the form of a flying machine but in corrections to the scientific record presented with full scientific support.  The Wrights were just as expert as anyone else in the field.  They were self-taught, to be sure, but not just yokels in comparison to supposed intellectual giants.  Where you differ from the Wrights is in your inability and unwillingness to demonstrate competence.  The Wrights did not accuse their critics and opponents of vast conspiracy or dishonesty.
« Last Edit: March 24, 2018, 11:41:48 PM by JayUtah »
"Facts are stubborn things." --John Adams

Offline Ranb

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Re: Radiation
« Reply #100 on: March 24, 2018, 11:35:09 PM »
Why bring my character, intelligence and technical competence into question?
You made your expertise (or lack of it) part of the question. 

.... I have stated that current data indicates the apollo data is unrealistic.  Prove me wrong.
That's not the way it works.  You made the claim (Apollo data is unrealistic), you prove it.
« Last Edit: March 24, 2018, 11:38:05 PM by Ranb »

Offline JayUtah

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Re: Radiation
« Reply #101 on: March 24, 2018, 11:40:28 PM »
Why bring my character, intelligence and technical competence into question?

Your character would be relevant only if it were necessary to assess such things as sincerity or ulterior motives.  I'm not interested in those.  Your intelligence is not being questioned, but your expertise is.  I'm not interested in whether those are the same thing.  Your expertise is being questioned because it's relevant to how much your judgment would be considered reliable in the relevant fields.  Your technical competence, as it relates to Apollo, is essentially irrelevant because it is in a field not related to space engineering or space science.

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Simply disprove the assertion and be on your way.

You're reversing the burden of proof.

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This should not not be difficult because I obviously lack the the knowledge or competence to understand the complexities involved.

And that is the refutation.  Your conclusion is not a self-evident fact somehow inexorably arising out of the materials you quote.  Your conclusion is the product of judgment we have determined is poorly informed.  When asked to explain why your judgment differs from those better qualified, you simply accuse them all of lying for apparently ideological reasons.

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I have stated that current data indicates the apollo data is unrealistic.  Prove me wrong.

You are unqualified to judge what is unrealistic in that field.  That's the proper refutation.  You seem to expect someone to make an affirmative counterclaim.

"Facts are stubborn things." --John Adams

Offline JayUtah

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Re: Radiation
« Reply #102 on: March 24, 2018, 11:45:17 PM »
This article speaks of shielding of  shielding up to 80 g/cm2 and 25 g/cm2..

"Speaks of" does not mean "establishes a requirement for."  That type of research is meant to be applied to all sorts of mission and spacecraft designs.  The mission designer is expected to interpret the findings consistent with his requirements.

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and correct me if I am wrong but the apollo had no radiation shielding at all and relied on heat shielding, equipment and superstructure to arrive at its estimate 10 g/cm2 shielding.

You seem to be operating under the misconception that radiation attenuation in spacecraft design requires components specifically designated as radiation shielding.  What is your experience in the design of spacecraft, manned or unmanned?
"Facts are stubborn things." --John Adams

Offline timfinch

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Re: Radiation
« Reply #103 on: March 24, 2018, 11:48:06 PM »
In summary, GCR is heavy, high-energy ions of elements that have had
all their electrons stripped away as they journeyed through the galaxy
at nearly the speed of light. They can cause the ionization of atoms as
they pass through matter and can pass practically unimpeded through a
typical spacecraft or the skin of an astronaut. The GCR are a dominant
source of radiation that must be dealt with aboard current spacecraft
and future space missions within our solar system. Because these particles
are affected by the Sun’s magnetic field, their average intensity is
highest during the period of minimum sunspots when the Sun’s magnetic
field is weakest and less able to deflect them. Also, because GCR
is difficult to shield against and occurs on each space mission, it is often
more hazardous than occasional solar particle events.11 The picture at
left shows GCR falling onto the surface of Mars. GCR appears as faint
white dots, whereas stars appear as white streaks.

https://www.nasa.gov/pdf/284273main_Radiation_HS_Mod1.pdf

Offline Ranb

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Re: Radiation
« Reply #104 on: March 24, 2018, 11:51:21 PM »
https://www.ncbi.nlm.nih.gov/pubmed/12056428

This article speaks of shielding of  shielding up to 80 g/cm2 and 25 g/cm2 and correct me if I am wrong but the apollo had no radiation shielding at all and relied on heat shielding, equipment and superstructure to arrive at its estimate 10 g/cm2 shielding.
The article is dated from 1963. 

You are wrong.  Apollo was built from metal of various types.  Even lightweight aluminum is useful as shielding.  We used it to reduce bremsstrahlung radiation in our beta counter when counting our primary coolant samples.