Radiation

[MBDK]

Secondary Flux on the Moon
Energetic particles and neutrons from cosmic rays induce nuclear reactions with target nuclei in the lunar regolith. Solar cosmic ray-produced secondaries are much less abundant than galactic cosmic ray-produced secondaries and occur primarily in the upper decimeter of the regolith. Since it is the energy of the incident particle that determines what reactions will occur, the GCR particles are of most concern. Typical particles with energies at MeV levels will induce reactions with an interaction mean free path of about 100 g cm-2. Thus, even GCR particles will interact with lunar surface materials at depths <5 m.

During the nuclear reactions (E >10 MeV) secondary particles are emitted; the original particle may emerge at a lower energy. Secondary neutrons and high energy particles can cause additional reactions. It is the secondary particles, especially the neutrons caused by GCR, that are relevant.

Solar wind particles are typically of such low energy that they penetrate no more than a micrometer. They can produce sputtered particles and can induce crystal damage. Most solar cosmic rays are stopped by ionization within the upper few cm of the regolith. The associated heavy nuclei are stopped in the outer millimeter. The main reactions produced by solar cosmic ray particles occur in the upper cm of the regolith, and few secondary particles are released.

Heavy nuclei in GCR radiation are usually stopped at depths <10 cm due to ionization energy loss, with most radiation damage occurring in the upper few cm. Shielding at a few g cm-2 is typically sufficient to remove most of the highly ionized heavy GCR nuclei. The lighter primary nuclei are more penetrating than heavier nuclei. Secondaries may be ionizing particles or uncharged, e.g. neutrons. The cascade that results from interaction depends on the energy of the incident particle and the nature (average atomic number) of the interacting material but can extend to depths of meters. Neutrons produced on the Moon typically have energies of a few MeV and travel until they interact or escape. Neutron interaction is most efficient with elements whose mass is lower than oxygen. Because such elements have relatively low concentrations (Table II), neutrons lose energy slowly and require many collisions to reach thermal energies (<0.1 eV).

https://www.lpi.usra.edu/wiki/lunaref/index.php/Lunar_Ionizing_Radiation_Environment


Moon dust is radioactive and this article is the definitive proof.  The  radiation reflected from the Moon raise the Background radiation in orbit around the Moon 30 to 40 percent.  Think about that for a minute.  The surface of the moon is so radioactive that it increases the radiation in the lunar orbit by 30 to 40 percent.  That is staggering.

Once again, his own source refutes him.  From the above reference:
"The ionizing radiation environment at the Moon, both in orbit and on the surface, consists of the solar wind, solar particle events (SPE, also referred to as solar cosmic rays) and galactic cosmic radiation."

Please note the absence of "radioactive Moon dust" as being included as part of the Moon's radiation environment.  This is because that dust's temporary radioactivity is caused by the GCR's secondary events - NOT neutron capture that makes the elements unstable, and thus causes them to be considered radioactive.  This has been previously explained, but like any good troll, he ignores that fact.

[Luke Pemberton]

During the nuclear reactions (E >10 MeV) secondary particles are emitted; the original particle may emerge at a lower energy. Secondary neutrons and high energy particles can cause additional reactions. It is the secondary particles, especially the neutrons caused by GCR, that are relevant.

So the secondary particles are relevant, not ionising radiation from radioactive isotopes.

Moon dust is radioactive and this article is the definitive proof.

Radioactivity and radiation are two different things. Yes, the outcomes are the same, in that ionising radiation offers biological damage due to deposition of energy. Radioactivity pertains to the activity of the nucleus. Ionising radiation has many guises. This cut and past from Wikipedia mentions nothing about radioactive dust.

The article even states that secondary neutrons are relevant. These result from strong force interactions between protons and the nucleus of the target material.

The radiation reflected from the Moon raise the Background radiation in orbit around the Moon 30 to 40 percent.

Radiation is not reflected in that sense. Please used words that pertain to relevant expertise in this subject.

The 30-40% figure is not refuted. In the abscence of this mechanism, say I have a baseline radiation of 0.1 mGy/day. What do I have if the figure is elevated by 30-40%. It's not the increase, but the outcome of the increase that is relevant. It's in the CRaTER data if you care to look.

Think about that for a minute.  The surface of the moon is so radioactive that it increases the radiation in the lunar orbit by 30 to 40 percent.  That is staggering.

If I have £1 in my bank account and deposit 40 p, that's not staggering. If I have £1000 000, and deposit £400 000, then that is a bonus. If I have £1 000 000 000 and deposit £400 000 000, then that is staggering. It's only staggering if what you start with is significant.

[timfinch]

So that we now understand that moon dust is radioactive.  Let's consider the implications of that finding.  There is nothing in a spacesuit to shield the neutron flux of the lunar surface.  The radioactivity of the regolith is a distinct health hazard and a decontamination chamber would have been required to keep from contaming the crew quarters.  The spacesuits would still have a tell tale radiation signature that could prove or disprove a lunar landing.   Why has no one ever mentioned that moon dust is radioactive?  Why wouldn't that be public knowledge?  Why am I the only one outside of NASA's secret Cabal privy to this information?

[MBDK]

https://www.lpi.usra.edu/meetings/leag2012/presentations/Stubbs.pdf

...and? What are you trying to show me, other then Cycle 20 was a more active time for the Sun than when the current CRaTER data was collected in cycle 24? So the three questions still remain:

• Have you interrogated the CRaTER data?
• How can you extrapolate between cycle 24 and 20?
• How does GCR flux vary with solar activity?

Nice graph.  Although the next few solar cycles WERE more active than 24, cycle 20 is also CLEARLY more active than cycle 20.  But trolls don't swallow facts, so I predict no admission of this simple truth from him.

Edited for this Note:  Post #688 admits the mistake in my second sentence and corrects it to what should have been posted.

[JayUtah]

Why has no one ever mentioned that moon dust is radioactive?  Why wouldn't that be public knowledge?  Why am I the only one outside of NASA's secret Cabal privy to this information?

Have you considered the possibility that you are interpreting this information incorrectly?

[Luke Pemberton]

YES

At what Julian dates?

The post clearly states solar cycle 20 was not as active as later cycles.

...except in the case of cycle 20. Cycle 20 is more active than cycle 24, my graphic shows that, and so do many other graphics from the literature. What cycle is the CRaTER data taken from and what effect would the higher activity of cycle 20 on the GCR influx. Assuming we can extrapolate of course.

GCR flux varies inversely with solar activity.

Good, so if cycle 20 is more active than 24, what do you think happens to the CRaTER data?

[timfinch]

https://www.lpi.usra.edu/meetings/leag2012/presentations/Stubbs.pdf

...and? What are you trying to show me, other then Cycle 20 was a more active time for the Sun than when the current CRaTER data was collected in cycle 24? So the three questions still remain:

• Have you interrogated the CRaTER data?
• How can you extrapolate between cycle 24 and 20?
• How does GCR flux vary with solar activity?

Nice graph.  Although the next few solar cycles WERE more active than 24, cycle 20 is also CLEARLY more active than cycle 20.  But trolls don't swallow facts, so I predict no admission of this simple truth from him.

cycle 20 is also CLEARLY more active than cycle 20"??

[onebigmonkey]

I'll try and simplify even further:

Some GCR might hit molecules on the lunar surface with enough impact to cause fission in some elements.

Some of those fission products might be directed upward.

Some of those fission products directed upwards might be long lived.

Some of those fission products directed upwards might have a half life long enough to possibly hit an astronaut's suit.

Some of the fission products that made it as far as the suit might possibly have the capability to go through the suit's protective layers.

As a non-physicist how am I doing? Anyone care to calculate probabilities?

[timfinch]

YES

At what Julian dates?

The post clearly states solar cycle 20 was not as active as later cycles.

...except in the case of cycle 20. Cycle 20 is more active than cycle 24, my graphic shows that, and so do many other graphics from the literature. What cycle is the CRaTER data taken from and what effect would the higher activity of cycle 20 on the GCR influx. Assuming we can extrapolate of course.

GCR flux varies inversely with solar activity.

Good, so if cycle 20 is more active than 24, what do you think happens to the CRaTER data?

[Luke Pemberton]

cycle 20 is also CLEARLY more active than cycle 20"??

It's a typo. Cycle 20 is clearly more active than 24, and the CRaTER data was taken in cycle 24. So answer my question. What effect would this have on the CRaTER data, assuming we can extrapolate?

[MBDK]

So that we now understand that moon dust is radioactive.  Let's consider the implications of that finding.  There is nothing in a spacesuit to shield the neutron flux of the lunar surface.  The radioactivity of the regolith is a distinct health hazard and a decontamination chamber would have been required to keep from contaming the crew quarters.  The spacesuits would still have a tell tale radiation signature that could prove or disprove a lunar landing.   Why has no one ever mentioned that moon dust is radioactive?  Why wouldn't that be public knowledge?  Why am I the only one outside of NASA's secret Cabal privy to this information?

It's not, as previously noted.  Do you KNOW the difference between secondary radiation and a radioactive element?  It has been previously explained, and you have used the terms, but your post indicates you don't, however, that is also indicative of troll behavior.

[timfinch]

I'll try and simplify even further:

Some GCR might hit molecules on the lunar surface with enough impact to cause fission in some elements.

Some of those fission products might be directed upward.

Some of those fission products directed upwards might be long lived.

Some of those fission products directed upwards might have a half life long enough to possibly hit an astronaut's suit.

Some of the fission products that made it as far as the suit might possibly have the capability to go through the suit's protective layers.

As a non-physicist how am I doing? Anyone care to calculate probabilities?

I think they already did.  The article provides expected resultant dose rates.  I did the hard part, you need only read the fruits of my labor.

[timfinch]

So that we now understand that moon dust is radioactive.  Let's consider the implications of that finding.  There is nothing in a spacesuit to shield the neutron flux of the lunar surface.  The radioactivity of the regolith is a distinct health hazard and a decontamination chamber would have been required to keep from contaming the crew quarters.  The spacesuits would still have a tell tale radiation signature that could prove or disprove a lunar landing.   Why has no one ever mentioned that moon dust is radioactive?  Why wouldn't that be public knowledge?  Why am I the only one outside of NASA's secret Cabal privy to this information?

It's not, as previously noted.  Do you KNOW the difference between secondary radiation and a radioactive element?  It has been previously explained, and you have used the terms, but your post indicates you don't, however, that is also indicative of troll behavior.

These are not my words.  I posted the article but I did not write it.  Other people, professional people are telling you moon dust and the surface of the moon are radioactive.  I'm just the messenger.

[MBDK]

https://www.lpi.usra.edu/meetings/leag2012/presentations/Stubbs.pdf

...and? What are you trying to show me, other then Cycle 20 was a more active time for the Sun than when the current CRaTER data was collected in cycle 24? So the three questions still remain:

• Have you interrogated the CRaTER data?
• How can you extrapolate between cycle 24 and 20?
• How does GCR flux vary with solar activity?

Nice graph.  Although the next few solar cycles WERE more active than 24, cycle 20 is also CLEARLY more active than cycle 20.  But trolls don't swallow facts, so I predict no admission of this simple truth from him.

cycle 20 is also CLEARLY more active than cycle 20"??

Yep.  I made a mistake.  I should have said "cycle 20 is also CLEARLY more active than cycle 24".

See how easy that is?

[MBDK]

So that we now understand that moon dust is radioactive.  Let's consider the implications of that finding.  There is nothing in a spacesuit to shield the neutron flux of the lunar surface.  The radioactivity of the regolith is a distinct health hazard and a decontamination chamber would have been required to keep from contaming the crew quarters.  The spacesuits would still have a tell tale radiation signature that could prove or disprove a lunar landing.   Why has no one ever mentioned that moon dust is radioactive?  Why wouldn't that be public knowledge?  Why am I the only one outside of NASA's secret Cabal privy to this information?

It's not, as previously noted.  Do you KNOW the difference between secondary radiation and a radioactive element?  It has been previously explained, and you have used the terms, but your post indicates you don't, however, that is also indicative of troll behavior.

These are not my words.  I posted the article but I did not write it.  Other people, professional people are telling you moon dust and the surface of the moon are radioactive.  I'm just the messenger.

Wow.  Now you include a quote of your own words, and say they AREN'T your own words.  No expert is telling me the Moon dust is radioactive enough to be considered a significant source.  Thanks for the laugh.