Radiation

[timfinch]

I do but it is important to note that the graph we speak of is summation graph where the detector outputs were added and averaged.

...and if you take the average of 2 points whose values are both less than 0.22 mGr/day, will your average be:

• less than 0.22 mGr/day
• greater than 0.22 mGr/day

The graph is derived from the very data that you laud before me.  How can you doubt the authenticity of the graph.  I didn't make it, they did.

You brought the data here, and we don't doubt the authenticity of the graph. You did not read the scale correctly.

Let us assume you are correct.  The graph is logarithmic and it shows what a minimum GCR background level of what?

[Jason Thompson]

I do but it is important to note that the graph we speak of is summation graph where the detector outputs were added and averaged.

Yes, and when you add and average a bunch of data points less than 0.2 you get an everage less than 0.2

How can you doubt the authenticity of the graph.

I don't, and I never have. As I said, I just put the data into excel and plotted the graph myself. It is only your interpretation of the graph that I doubt.

[Jason Thompson]

Sure it is, a logarithmic graph is plotted using the log of the data points and not the data points themselves

You have GOT to be kidding?

A logarithmic scale is used to plot data points with a wide dynamic range on a single scale. It is absolutely NOT done by changing the data points, only by changing how the scale is presented. In this case it allows the fluctuation in the baseline levels to be seen even when all the SPE spikes are plotted on the same graph.

Incidentally, I do this kind of data plotting, manipulation and interpetation for a living.

Like I said earlier, download the data and plot the graph yourself.

[Jason Thompson]

Let us assume you are correct.  The graph is logarithmic and it shows what a minimum GCR background level of what?

Read the numbers Tim. For the love of god look at the actual data and find the minimum yourself.

[Luke Pemberton]

Sure it is, a logarithmic graph is plotted using the log of the data points and not the data points themselves

I think I see the confusion. Your confusing two things here. A log scale and a log graph related to monomials. If I have data that I think has the form y = ax^k, I will take a log of the data. If the data has this form then

log y = log a + k.log x

will fit to a straight line.

If I have data that changes by orders of magnitudes, I plot that data on a log scale, so the variation of the small numbers show up as well as the large number. I don't take the logs of my data when I choose a log scale.

The data on your graph is represented by a log scale as the data changes by orders of magnitude for the SPE events.

[timfinch]

Consider this article from a Nasa web site.

Cosmic ray fluxes, consisting of completely ionized atomic nuclei originating outside the solar system and accelerated to very high energies, provided average dose rates of 1.0 millirads per hour in cislunar space** and 0.6 millirads per hour on the lunar surface. These values are expected to double at the low point in the 11-year cycle of solar-flare activity (solar minimum) because of decreased solar magnetic shielding of the central planets. The effect of high-energy cosmic rays on humans is unknown but is considered by most authorities not to be of serious concern for exposures of less than a few years. Experimental evidence of the effects of these radiations is dependent on the development of highly advanced particle accelerators or the advent of long-term manned missions outside the Earth's geomagnetic influence.

https://history.nasa.gov/SP-368/s2ch3.htm

I am not sure but I think 1 millirad/hour is equal to .24 mgy/day.  Correct me if I am wrong.  This article was written back in the seventies.

[bobdude11]

The simple test is to check for linearity.  If the data is linear then it is not a logarithmic graph.

Tim, do you or do you not acknowledge that data is recorded in that set that clearly shows levels of less than 0.2mGy/day were recorded?

Secondly, here's a simple test for you. Download that data into Excel and plot the graph. It just took me all of five minutes to do that, and when I put the y-axis to a log scale lo and behold it looks just like that graph.

I do but it is important to note that the graph we speak of is summation graph where the detector outputs were added and averaged.  The graph is derived from the very data that you laud before me.  How can you doubt the authenticity of the graph.  I didn't make it, they did.

I think my brain just committed suicide on this one.

[Jason Thompson]

Consider this article from a Nasa web site.

No, do not shift to something else once you run out of ways to weasel out of admitting your interpretation of the data you so adamantly insisted supported your point was wrong.

[Luke Pemberton]

Consider this article from a Nasa web site.

No, let's establish your understanding of log scales and log graphs, and whether you can now concede that the data you brought here actually fulfils the criteria set out in your initial premise of <0.22 mGr/day.

[timfinch]

Sure it is, a logarithmic graph is plotted using the log of the data points and not the data points themselves

I think I see the confusion. Your confusing two things here. A log scale and a log graph related to monomials. If I have data that I think has the form y = ax^k, I will take a log of the data. If the data has this form then

log y = log a + k.log x

will fit to a straight line.

If I have data that changes by orders of magnitudes, I plot that data on a log scale, so the variation of the small numbers show up as well as the large number. I don't take the logs of my data when I choose a log scale.

The data on your graph is represented by a log scale as the data changes by orders of magnitude for the SPE events.

I recognize that I can't change your mind and I will leave you with your interpretation.  I am moving on.

[timfinch]

https://en.wikipedia.org/wiki/Logarithmic_scale

[Jason Thompson]

I recognize that I can't change your mind and I will leave you with your interpretation.  I am moving on.

Tim, this is not interpretation, this is standard mathematical practice. You are moving on because you won't actually do the simple thing that has been suggested and look at the data yourself. As I said, it took me all of five minutes to download the data into Excel and plot the exact same graph using that data on a logarithmic scale. Why exactly are you so unwilling to take five minutes of your time to do the same thing and tell us how it went?

[Luke Pemberton]

I recognize that I can't change your mind and I will leave you with your interpretation.  I am moving on.

It's not a case of changing my mind. It's a case that you thought the data was converted with logarithmic functions first when actually it is the scale that is chosen to be logarithmic. There's a difference.

Now you've seen the data, that you brought here, do you agree that the levels can be less than 0.22 mGr/day. If not, why not?

[Jason Thompson]

https://en.wikipedia.org/wiki/Logarithmic_scale

Nothing  in there contradicts what we have been saying about that graph, Tim.... The y-axis is logarithmic, the x is linear. As I have said before, you can actually do this yourself with that exact data set. Why will you not?

[onebigmonkey]

Ah, I wasn't expecting a return to the debate!!

I do have a question for Mr Finch, as regards the measured, or generally accepted figures for radiation levels in space beyond the VAB.  (I originally brought it up in post #550, but I'll summarise here as well.)

I work for a company which develops data handling technologies* for spacecraft.  I'm on the software side of things, but I know our chip design folks have to consider a lot of factors about the environment their designs will be used in.  Since the data they're using is based on the generally accepted measurements and models, why aren't there a lot more failures of missions operating in these regions?

As I also noted in my previous post, it's not just NASA that's involved in determining radiation risks, but private companies and other organisations in the US, and around the world, and even small independent groups like the Lunar X-Prize teams.

Either :
a) the failure rates are being covered up, or
b) all the engineers, all over the world, are in some great conspiracy to lie about the figures, or
c) all missions outside of LEO are fakes, or
d) the space radiation environment has been correctly measured and modelled, and allows for safe design of both manned and unmanned missions

Which, in your opinion, is the explanation?


[ * The same technology has been used on well over 100 missions, including LRO, MRO and Mars Express, and will launch on BepiColombo, JWST and several other upcoming spacecraft.]

The technology obviously exist to operate electronic equipment in the SAA and passing through the VAB.  Missions in this high radiation background have shorter life expectancies than missions that remain in LEO.  I can't begin to answer your question without comparative data.  I am sure redundancy and hardened equipment was used in designing electronic equipment for the hazards of space.  What has any of this to do with my claim that Apollo 11's mission dose is unrealistic in light of recent empirical data?

Ah, the joys of being in a different time zone... 

The relevance to the Apollo missions is that the data used for shielding, design of rad-hard electronics etc. is based on the measurements over many years, starting pre-Apollo.  The published, currently available data, which has been used for many, many missions, shows that the environment outside LEO and the VAB is not as hostile as you claim, and certainly not enough to prevent manned lunar missions.

You're claiming that this data, used by engineers in many countries, is incorrect, and misrepresents the actual environment, but the success and reliability of missions to the Moon, Mars and beyond, to Lagrange points etc. says otherwise.

Perhaps you ought to familiarise yourself with spacecraft reliability and failure data, because radiation damage is not the primary cause of missions failures (even ignoring launch failure and human errors).

Why would I.  I have made no claims about mission survivability.  I don't even claim that the radiation hazards are insurmountable.  The only claim I make and am willing to defend is the mission doses of Apollo 11 do not represent realistic values in light of current data.  Anything else is yours.

Speaking from a non-expert in this field, no, no you are not willing to defend. Hand-waving, deflection, insults, those are your 'debate' method of choice. You have not made any argument that I find remotely convincing. On the other hand, I have read about all of the missions around: Apollo, Gemini, Mercury, Space-X, the Space Shuttle, and even what I can about various Russian (pre- and post- Cold War), and Chinese space missions. What I can say is this (obviously from a very layman's' perspective):
All these missions all occurred as recorded and the data around them is irrefutable. The experts on this forum have bent over backwards to steer you in the direction of a correct diagnosis of the data.
Instead you choose to ignore the information presented, instead you repeat your incorrect assumptions, demand they offer something (I am not sure what) to refute you (which they have repeatedly done. You then, when you don't get the answer you demand, begin insulting them. You have proven post after post that you do not understand what you are reading, bluster about your military experience (which sounds to me like a standard certificate course the military provides - I have one for my Security Police training, that doesn't make me a lawyer), and refusal to admit that your initial diagnoses and determinations were simply wrong.
Please stop being obtuse and either admit your are wrong or just go back to your sycophantic forums.

Sycophantic?  I am an island in a sea of like minded people and you speak to me of sycophants.  There is as much separation in the collective thought pattern of this forum as there is space between the protons and neutrons of a helium atom.  Not an original thought exist in the lot of you.

and we're back on the insults. You want original thought I have a whole website that is no-ones work but my own. Proves you wrong every which way you look at it.