Apollo Investigation/Spaceflight

Orion, the Van Allen Belts & Space Radiation Challenges

by Mary Bennett
 


The BIRD Radiation Detector report seemingly confirms that the dosimetry radiation data for the manned Apollo lunar flights was collected while remaining in low-Earth orbit.

Background

The Best of Times

Orion

The December 2014 Orion test flight was flown in preparation for manned explorations to the Moon and to Mars.
With a trajectory designed principally to examine the heat shield performance at re-entry, Orion had to make a highly elliptical orbit taking it some 3,600miles/5,800km off the surface of the planet into the region of the lower (or inner) Van Allen belt. As a result, even though Orion’s apogee was well shy of the worst part of this inner belt, (another 2,344 miles further out) Orion carried instrumentation for registering the radiation environment in the craft’s interior.[1]

Exploration test Flight

Exploration Flight Test One

Given the advanced electronic systems that the Orion craft would be using, and the future astronaut occupants, this test made engineering sense – yet it didn’t feature very much in the pre-flight literature. If the NASA Orion Blog for November 2014 carried a vague mention of this particular test, it also managed to convey the notion that radiation would only manifest at the moment of re-entry:

Although Orion will not carry any people on its flight test, it’s designed for astronauts, and engineers want to find out what conditions will be like inside the cabin as Orion travels through high radiation and extreme temperatures during this flight test.[2]
Orion

The very colourful NASA Orion Press Kit doesn’t refer to radiation data acquisition at all, nor was it listed among the flight objectives of this 2014 test.[3] Perhaps the Press Kit was for the ‘ordinary media’, as the specialist website Spaceflight101 did mention this aspect of the Orion test:

‘In this elliptical orbit, Orion will have to pass through Earth’s radiation belt Radiation inside the Crew Module will be measured to evaluate shielding materials that will protect future crews in the harsh radiation environment of Deep Space.’ [4]

This statement ignores basic punctuation and technical accuracy; firstly Orion did not pass through the belt(s) it merely skimmed the edge of the lower belt. Secondly, it infers that radiation in ‘Deep Space’ is harsher and somehow different. From what? Shallow Space, Softer Space? Interestingly, at one point in the Orion radiation report, just after the instrumentation had registered a spike in an extremely potent area of the inner belt, the radiation is described as ‘softening’:

‘Upon entering the trapped belts, a region of high absorbed dose rates was encountered, followed by a local minimum, caused by a softening of the trapped proton energy spectrum.’

These might be ‘technical terms’ used by ‘experts’, but when presented to the general public there is the potential for the manipulation of reality through vocabulary. The dividing of space into cislunar space (the region of space within the orbit of the Moon) and deep space, (beyond lunar orbit) lulls the public into false assumptions concerning the safety of manned spaceflight and has little to do with the reality of the space environment.

NASA documents that adopt these terms when explaining that deep space missions are more dangerous for astronauts than cislunar or near-Earth expeditions are merely stating the obvious. Clearly, the longer one is out in space the higher the probability of encountering problems of ionising radiation over and above the extant background levels. If Curiosity’s outward-bound radiation data acquisition has amply made that point,[5] it also doesn’t take a genius to understand that the accumulated, or total dose received by an astronaut over time, is going to be more for a longer trip and will only be mitigated by the quality of protective shielding provided.

However, this division of space into separate zones does not mean, in terms of time and distance, that travel to a location comparatively near to Earth such as the Moon or one of its Lagrange points, is less risky. Yet this is the notion that NASA would prefer everyone to accept, stating that the Moon is 'only a few days away but Mars is 15 months away in some scenarios’. If NASA uses this language it is hardly surprising that others repeat it.

Dose Equivalent

US radiation dose rates. Mars data from the Curiosity outbound trip and the RAD detector on the landed probe.
Note this scale is drawn in logarithmic increments.

Radiation
See footnote [1] on radiation. WNA, radiologyinfo.org, Reuters

The Worst of Times

In 1966, three years after starting work on 2001: A Space Odyssey, and fully aware of all the issues involved with manned spaceflight, Arthur C Clarke noted that the Apollo manned space flights would be getting underway at the very worst time of the solar cycle. He noted that: "the astronauts would be travelling under the worst possible conditions, should solar activity occur, the astronauts would start to die of radiation problems in a few hours”.

Offering the politically useless recommendation for Apollo that generally speaking the astronauts only travel at solar minimum, and the physically useless recommendation (if the Moon was the destination) that astronauts should stay within the Earth’s atmosphere at times of solar events, Clarke added: "A careful watch for solar flares will always give us a day’s warning of an approaching storm, and this will be no handicap for lunar travel, for flights to the moon will last no longer than this."[7]

Clarke ostensibly ignores the fact that it was calculated that to reach the Moon in an Apollo CSM it would take around four days, and that the Moon is totally unprotected from space radiation.

By 1970 Clarke had modified his opinion. “A few hours flight time away from Earth, one can always come home in a hurry.”[7] Yes, Arthur, if in LEO, and not on the way to the Moon. Given the limitations of rocketry and orbital mechanics when it comes to a lunar mission, this was, and still is, inaccurate. Such fallacies uttered by 'celebrity experts’ are accepted by the general public as scientific truths. In 1993 NASA’s Space Radiation Analysis Group (SRAG) had this to say about the Apollo missions and solar activity:

Between the Apollo 16 and 17 missions, one of the largest solar proton events ever recorded occurred, and it produced radiation levels of sufficient energy for the astronauts outside of the Earth's magnetosphere to absorb lethal doses within 10 hours after the start of the event. It is indeed fortunate that the timing of this event did not coincide with one of the Apollo missions… accurate prediction of solar particle events still is not possible. In addition, the biological effect from long term exposure to high energy galactic cosmic radiation is not well understood.

We were no better off in 2014. The SRAG website[8] was last updated and reviewed that year, and hosts a page explaining the considerable resources invested in round-the-clock-monitoring of the Sun’s activities. Something of great importance for those on the ISS. While another page on the same SRAG site states that Solar Particle Events (of which solar flares are a part) are of particular concern to astronauts and that these SPEs are IMPOSSIBLE to predict in advance.

Notwithstanding the ’good fortune’ enjoyed by Apollo, it’s time to put a stop to the myth that everyone is mostly safe from radiation hazards in LEO, somewhat unsafe from LEO out to the Moon, and terribly unsafe beyond lunar orbit to Mars, Venus or elsewhere. When it comes to ionising radiation the problems for a human potentially start to build as soon as an astronaut leaves the Earth’s atmosphere.

Radiation Hazards
Radiation hazards affecting satellites, spacecraft and Earth technologies (UK Meterological Office)

With Orion’s current technical configuration, the final architecture of the shielding (should it ever get to the point of going somewhere other than high LEO) will have to be a trade-off between the amount of risk NASA considers acceptable for the crew, and its ability to launch the resultant spacecraft into the desired trajectory.[9]

The Other Beltway

Taking all the above into consideration, it’s no surprise that the study of the Van Allen belts (VABs), on-going since the late 1950s, continuously astonishes us. Having been attacked from below by human beings during various nuclear tests – among which US Operations Argus and Starfish Prime[10] – the belts have also revealed themselves to be far more unpredictable than expected, showing a variation in responses to apparently similar solar events impinging upon the region. In early September 2012, a few days after the launch of NASA’s two Van Allen probes, the REPT (Relativistic Electron & Proton Telescope) experiment recorded the existence of a third belt which not only affected the inner regions but also extended the outer belt much farther into space than ‘usual’.

This situation lasted for four weeks before restoring to 'normal' and scientists seriously considered that textbooks asserting that the VABs consisted of two distinct zones of trapped, highly energetic charged particles, (chiefly protons in the inner/lower belt and electrons in the outer/upper belt) would have to be rewritten.

The University of Colorado’s Daniel Baker, Principle Investigator for the REPT, and first author of the science paper published on 28 February 2013[11] made a really useful comparison between the VABs and the particle storage rings in a particle physics accelerator:

In accelerators, magnetic fields are used to hold the particles orbiting in a circle, while energy waves are used to buffet the particles up to ever faster speeds. In such accelerators, everything must be carefully tuned to the size and shape of that ring, and the characteristics of those particles. The Van Allen Belts depend on similar fine-tuning. Given that scientists see the rings only in certain places and at certain times, they can narrow down just which particles and waves must be causing that geometry. Every new set of observations helps narrow the field even further.

With the potential for a wide variability in the VAB’s activities at any given time, it clearly makes sense to monitor the VABs at every opportunity and it is entirely understandable that the organisers of the Orion test would want to run yet more evaluations of the conditions to which the Orion astronauts would be subjected, in the lower portion of the belts at least (because in terms of distance from the apogee of the Orion flight the belts continue for another 6.5 radii before the energy from the outer belt normally declines).

Van Allen belts

1958 section of the Van Allen belts with the maximum distance of the Orion EFT-1 test from the surface of the Earth added. Section: James Van Allen. Annotation Aulis

Foreground

A Case of Simple Avoidance


Just why such monitoring should then be considered an unmentionable item for the Orion flight objectives is rather a mystery. As is the fact that when the technical reports for Orion EFT-1 were published on NASA’s Technical Report Server, it included an incorrectly titled PDF document on the engineering undertaken for the protection against radiation for the Guidance Navigation & Control (GN&C) components of the spacecraft[12], but the radiation data acquired by Orion relative to the interior of the craft and its future human occupants was not immediately apparent.

As it turned out, for that data to be available a FOIA (US Freedom of Information Act) request was required. That was a saga in itself and best told by the participant[13] who kindly sent us a copy in September 2015. The report was dated 01-06-2015 and I saw that the reference for accessing this ‘UNCLASSIFIED document with unlimited distribution’[14] was the very NASA Technical Report website where it was only remarkable by its absence. However some weeks later, this report was posted on another NASA site, under a completely different electronic title.[15]

The manifest disinclination to place the results of these findings in the public domain implies that the radiation data obtained during the Orion test was of greater significance than indicated by NASA’s casual attitude during the run-up to the test. It also implies that the results would be of such importance that it was necessary to keep any mention of radiation out of the Press Kit and, in NASA’s own Orion blog, categorise the radiation research as by-product of the heat shield testing.

Or, it could be interpreted as a whistle-blow from inside NASA. After all, there was no need to stipulate an FOIA request on unclassified material which was going to be released into the public domain. Yet releasing it in a way which could not be sourced – unless one knew the relevant electronic title – fulfilled the obligation to publish without actually making it readily available. Until the new link was made known to interested parties – although not necessarily all NASA enthusiasts. That old joke about the NASA acronym standing for ‘Never A Straight Answer’ certainly applies to these convoluted deeds, as it does to the contents of this report.

Mystery Writers

Obfuscation when describing its principal results, it doesn’t read like the usual NASA technical report, but as if written for the benefit of ‘civilians’ outside NASA. Comprising input from authors representing three Houston-based organisations: Lockheed Martin Information Systems & Global Solutions, the University of Houston and NASA Johnston Space Center, (which finally posted it on the web), it had the snappy title 'Battery-operated Independent Radiation Detector Data Report from Exploration Flight Test 1'. The title reveals once again, the NASA preference for symbolic acronyms over scientific brevity, for this Orion radiation package then becomes BIRD. Bird is the USAF slang for flying machines. Moreover, this acronym also fits the starry Egyptian symbolism preferred by NASA and which infuses the Orion program.

It’s a moot point as to whether this particular BIRD refers to the solar Benu bird often associated with the pyramid builders, but as far as radiation goes – that would be a neat fit. And I began to wonder if that other mythological solar god Apollo, had anything to do with the coyness of NASA, because according to the historical record, the only manned flights that have experienced space beyond LEO are the Apollo missions, of which, over and above Arthur C Clarke’s previous comments, SRAG[8] in 1993 had this to say:

'Apollo missions were fortunate to avoid random solar proton events through short mission duration… Future missions will involve longer stays, making simple avoidance less practical.'

One wonders how ‘simple avoidance’ can actually work, when flying a fixed orbit to the Moon over a period of say eight days for Apollo 11. From this statement, the secret recipe for Apollo success apparently consisted of a large dollop of good fortune and a smidge of shielding, allied with a quick dash of anything from 6 to 12.5 days, and served with a sauce of totally unpredictable solar activity. Unless of course, ‘simple avoidance’ means very simply not leaving Earth’s magnetosphere at all. Not according to NASA, for again the agency assures us that Apollo is the exception to the rule:

Except for the Apollo missions to the Moon, NASA's manned spaceflight missions have taken place within the cocoon of the Earth's magnetosphere. As NASA ponders the feasibility of sending manned spaceflight missions back to the Moon or to other planets, radiation protection for crew members remains one of the key technological issues which must be resolved.

Which clearly implies that this issue had not been resolved for the Apollo program.

In the light of all this, it was worth checking the Orion radiation results to see if there were any data relevant to Apollo within its pages which might explain the reluctance of NASA to post its findings. I was astonished to find that in relation to evaluating radiation problems outside the magnetosphere for future lunar and Martian missions Apollo was simply ignored. In another section of the SRAG documentation[8] of 2012 on radiation measures to be taken relative to human spaceflight, we are informed that:

'NASA has a history of radiation risk management, from Apollo, Shuttle, and ISS. Radiation monitoring requirements from the ISS and Shuttle had been incorporated into planning the Constellation Program.'

Orion is what remains of the reduced-budget Constellation Program,[16] and during its next unmanned flight test pencilled in for 2018, it is scheduled to fly around the Moon. Yet even the data from Apollo 8 – the most comparable of the Apollo missions to Orion, a CSM round-the-Moon flight – has been deemed totally irrelevant!

Granted, the shielding architecture of the Apollo CSM was not in the same league as that of the Shuttle, the ISS, and Orion, which might make the Apollo data of little value to engineering decisions made for the final Orion MPCV shielding materials. But given the unique status of Apollo relative to manned spaceflight, it's a little difficult to understand why the Apollo dosimetry (radiation measurements) would not be evaluated along with the Shuttle and the ISS dosimeter readings – unless the Apollo dosimetry data are in some way not representative of the effects of radiation on humans and are therefore irrelevant as far as the Orion EFT-1 goes.

The Phantom Skull

With the Space Shuttle now defunct, NASA chose to compare Orion’s BIRD data with the current situation on the ISS. Yet radiation research on the human bio-organism had been quietly undertaken on the Shuttle, often on classified Department of Defense (DOD) missions.

So, before dismissing the Shuttle entirely, and to put the low-Earth orbit (LEO) environment into context, some previous research into radiation undertaken by Shuttle crews is worth mentioning. Firstly, this description of Shuttle flight Columbia STS-28, (57-degree high inclination orbit) published on NASA’s SRAG site is helpful:

The galactic cosmic ray (GCR) component varies cyclically with maximums at the extreme northern or southern portion of the orbital track. Minimums correspond to transits of the geomagnetic equator, where the spacecraft experiences the maximum geomagnetic protection from GCR. At periodic intervals large spikes in the exposure rates are encountered which correspond to passages through the South Atlantic Anomaly (SAA). The largest spikes are passages through the regions of peak SAA intensity; smaller peaks represent passage through the fringes of the SAA.

A unique feature of this [STS-28. and should read: ‘these data’] data are the effects of a solar particle event measured in LEO. Peaks in the dose rate attributed to the Solar Particle Event (SPE) occur at the extreme northern or southern portions of the orbital track. Whereas the GCR and SAA components shown in the figure are "typical" for high inclination flights, the effects of SPEs on dose rates will depend upon a variety of parameters. emphasis added.[8]

This 8-13 August 1989 flight, the first since the Challenger disaster, took place under a curtain of secrecy since it was carrying DOD equipment. NASA spokesman Brian Welch was terse as to the flight details. No data other than the 57-degree high inclination to the equator of its orbit was then available. Kept just as secret as the DOD’s mission was the fact that Columbia carried an 11lb female human skull. Donated for science, this ‘skull phantom’ (as it's known in the medical supply trade) was going to contribute to NASA radiation research, as apart from launching DOD material, Columbia was going to evaluate the penetration of radiation in the cranium. As the primary component of the ‘In flight Radiation Dose Distribution equipment’, this skull was slightly reconfigured:

‘The $1,500 skull had been sliced into sections an inch thick, so medical researchers at Johnson Space Center could install more than 100 radiation detectors. Then it had been reassembled and covered with plastic that was affected by radiation much like human skin.’[17]

The prepared skull was then put inside a locker on the Shuttle’s mid-deck and monitored on a daily basis by the crew. This is not where a crew member would generally stow themselves. And would not this locker provide extra shielding and potentially falsify the readings?

Astronauts become exposed to more radiation at higher inclinations, so the skull would fly again in the mid-deck locker on Atlantis STS 36 in February 1990 at a 62-degree inclination orbit; and as radiation levels also change with altitude as well as inclination, the skull was placed in the mid-deck locker of Discovery STS 31 in April 1990 and flew to its highest altitude of 380 miles, during the Hubble launch, at which time news of the skull’s presence on its maiden flight on Columbia STS-28 broke in Aviation Week. The results of the research did not, even though the skull and STS-28 experienced a large SPE event the day before the mission ended.

Aulis readers[18] will recall the reservations of NASA's spokesman on the subject of human medical issues in space when interviewed by Michael Crichton prior to the STS-28 flight. Crichton later published the article America Beyond (After the Challenger Disaster) The Future of Man in Space, as anticipated by NASA on the eve of the resumption of Space Shuttle flights,[19] and eventually NASA-SRAG published the technical graph from STS-28 illustrating the contributions of the three natural sources of radiation:[20]

Measured Dose
Measured dose rate vs. time for a high inclination Shuttle flight [STS-28]
[during which] A large solar proton event occurred toward the end of the mission

Moreover, SRAG also have this to say about the radiation effects of flying through the regions used by the Shuttle and the ISS:

Low inclination, high altitude flights during solar minimum produce higher dose rates than those with high inclination, low altitude flights during solar maximum. At higher altitudes, the area of the South Atlantic Anomaly is larger and the concentration of protons is higher. Although trajectories of high inclination flights pass through the regions of maximum intensities within the South Atlantic Anomaly, less time is spent there than for low inclination flights, and crews on high inclination flights typically receive less net exposure to trapped radiation for the same altitude.

Note that the Columbia & Atlantis Shuttle flights, STS 28 & STS 36 respectively, were high inclination and relatively low altitude flights, while Discovery STS 36 at 28.45 degrees was a low inclination, high altitude flight. As was the 28.8 degrees, very high altitude Orion EFT-1 flight. As for the ISS, it orbits in LEO at the high inclination of 51.65 degrees, so that it can be served by the Russian Soyuz and Progress spacecraft. The maximum safety altitude for the ISS relative to radiation dangers is 500km/310miles, but it generally operates to a maximum of 400km/248miles.

Bearing in mind that the Orion MPCV flown on EFT-1 was a work in progress, due to be retested after evaluation of the EFT-1, the differences with the Orion data can certainly help evaluate the issues raised by a spacecraft flying, in Orion’s case, into the lower proton belt. Despite these limitations, the results published in this report are important – for whatever the state of Orion shielding during this test, the amount of radiation actually registered can give a benchmark as to the margin of difference between LEO and the VABs.

Composite Orion
Orion flight overlaid onto the South Atlantic Anomaly. Orion trajectory NASA, SAA, Wikipedia

Time Bandit

From launch to splashdown Orion flew for 4.5 hours and the ISS-TEPC radiation detectors were assessed during that exact same period against the data from Orion’s detectors.[21] The ISS-TEPC is the station’s Tissue Equivalent Proportional Counter and is important for any flights above an altitude of 381.4km/237miles. Reading between the lines of NASA publications it turns out that these instruments are themselves vulnerable to the space environment and although upgraded whenever possible, the instruments still fail on a fairly regular basis.

Although though the BIRD graphs as published in the report start some 2 minutes after launch and go through to splashdown, 4.5 hours later, in reality, for the first 11 minutes BIRD was travelling within the Earth’s atmosphere and later, after Entry Interface it took Orion another ten minutes to splashdown. So that while NASA uses the full 270 minutes when comparing the Orion cumulative absorbed dose findings to that of the ISS, strictly speaking – a period 249 minutes for Orion would be more realistic. This shorter period of time set against the ISS 270 minutes would only make matters worse in terms of the findings. That might be another reason why this data was initially hard to find, because for anyone attempting to get into space with humans in the foreseeable future, these figures are by no means encouraging.

The BIRD report is fairly technical and the interested reader can help themselves to its contents via the link.[15] Here, the summary of the findings from the radiations detectors on ISS and Orion [12p39] can simply be extrapolated. They begin with an interesting point of view:

‘The EFT-1 mission presented the first opportunity to take radiation measurements on the Orion MPCV. The BIRD acquired radiation data that are vital for understanding the impacts of transient trapped belt radiation exposures on crew health and safety for future crewed exploration missions.’

It might be the first opportunity for Orion, but it was not the first opportunity to understand the impacts of the VABs on human beings. This document consistently uses 'belt' and 'belts' incorrectly. Notwithstanding the Apollo issue, every probe to Mars has provided opportunities to do the same.

‘The BIRD data provided a preview of the radiation environment that the crew will encounter while transiting the trapped radiation belts on future exploration missions.’

The choice of term ‘preview’ emphasises the fact that Apollo is irrelevant and has long been forgotten. And given the variable nature of the VABs and the solar cycle, it is not certain that the next manned mission will encounter the same environmental circumstances, it would be more accurate to say ‘the BIRD data provided a contemporary assessment’ rather than ‘a preview’, but that would be to recall Apollo in the minds of the public.

'Prior to entering the trapped belts, the undulation of the GCR as a result of the varying intensity of Earth’s geomagnetic field is observed [in the graph below]':

Orion Dose Rate
Dose rate in silicon and water for each frame (dots) and computed using equation 3 where the sum is over a 1-minute period (solid line).

'Upon entering the trapped belts, a region of high absorbed dose rates was encountered, followed by a local minimum, caused by a softening of the trapped proton energy spectrum.'

Note this region of high absorbed dose rates lasted some 20 minutes and that the local minimum is only minimum relative to the high just experienced.

'The second region of high absorbed dose rates occurred just after the maximum altitude was reached. The maximum absorbed dose rate was found to be about 1 mGy/min, 20 times the alarm level for the ISS-TEPC.' [emphasis added]

This second region occurred just after the 3,600 miles altitude and lasted about 40 minutes according to the graphs.

Orion Test Flight
Reuters, NASA, Tribune News Service

Note that this graph is not entirely accurate, the apogee of the flight’s 3,600mile altitude is far too close to the 3,000mile marker. The summary carries on to state:

‘It is important to note that while these absorbed dose rates are very high, the exposure is transient. For nearly 4.5 hours of mission time, the total absorbed dose to the detectors was less than 20 mGy (water).'

The exposure is not all that transient. A total of 60 minutes was spent in regions of high radiation – that's just under 25% of the total mission time spent beyond the atmosphere. And whether acquired in an instant or over time during the flight, the effects of these high radiation events are accumulated within the systems experiencing them. According to Van Allen’s mapping of the belts in 1958, the density of particles experienced by Orion at 3,600 miles up continues out to at least 15, 852 miles, well after the electron peak. So to say that the exposure is transient is true – but only with regard to this particular test flight.

'The results from the BIRD detectors compare favourably with the RAM results, as shown in Table 1. Differences in the order of 10%-15% for co-located RAM and ISS-TEPC detectors are common on the ISS.'[21]

This bit of techno-speak is useful for the engineers when building the next set of detectors for Orion. And such reassurances seem designed to offset the next portion of this same paragraph, which is a stunning bit of NASA-speak:

'It is also interesting to note that the cumulative absorbed dose as measured by the ISS-TEPC during the EFT-1 mission was about three orders of magnitude, or 1000 times, less than the cumulative absorbed doses measured on the Orion MPCV.'

At first glance this may sound alright. Less is good. But in fact this sentence was written backwards: the Orion detectors were registering three orders of magnitude higher than the ISS.

Absorbed Dose
BIRD table 1 p23. Taking the most conservative Orion figures at 15.7 (BIRD) or the highest RAM 15.1 the readings from Orion were three orders of magnitude higher than those of the ISS, which was reading at 0.015 mGy.

This is where it now gets interesting, because the Apollo dosimetry data had been registered by the National Council for Radiation Protection & Measurement (NCRP) in 1998 in the same mGy and on the same type of dosimeters as the RAM, and the ISS-TEPC. So comparing the RAM on Orion to the Apollo data, I ought to find that Apollo was up there with Orion, or worse, given the state of the art in constructing the CSM then, and today.

Here are the Apollo mission data from the NCRP expressed in mGy, and which agree with another table published by NASA in 1973 but expressed in RAD.[22],[6]

Apollo Dosimetry

Taking for example, the Apollo 11 flight daily dose of 0.22mGy, and dividing by 24 to find a dose rate of 0.00916 per 60 minutes, gives a dose rate of 0.038014 for a period of 249 minutes. This is about twice as much as that registered by the ISS, namely 0.015mGy for the 270 minutes of the Orion test. Taking this time of 270 and doing the same calculation, the Apollo 11 data would only be marginally increased to 0.04mGy. These figures are nowhere near the 15.1mGy registered by Orion but they are near to the figures registered by Apollo missions operating in LEO.

When comparing this Apollo 11 outcome with Apollo 7, which was acknowledged to be orbiting in LEO with a perigee of 229 and an apogee of 309 miles, (the top end of the ISS comfort zone) we find Apollo 7 with a 0.025mGy against 0.04m for Apollo 11. Not really believing these results, I then thought to check out the Apollo flight that had been attributed the highest doses of radiation: Apollo 14 received a 1.27 daily dose rate which comes to 0.219mGy for those 249 minutes. All the Apollo flight radiation data in the NCRP table compare more closely with the ISS–TEPC data from LEO than they do with the Orion RAM figures.[24]

The fact that the Apollo data is out of synch with the ISS and Orion might explain why it is totally ignored by the industry today.

It would also explain the problems surrounding this BIRD report.

More especially since better methods of evaluating radiation effects on astronauts have only made things worse: the amount of radiation tolerated by a human beings varies considerably, and the effects of radiation on the human organism are still at early stages of understanding. However, results from a 2006 study indicates that protons from cosmic radiation may cause twice as much serious damage to DNA as previously expected, exposing astronauts to greater risk of cancer and other diseases. Yet, the high dose radiation only now being taken into account, through better measurement and a longer experience of human beings in space has always existed and had to be endured by all machines and bio-organisms travelling through it.

Today then, rather than the cavalier attitude expressed in the US during Apollo[24], radiation exposure to astronauts both in LEO and beyond is now a major concern, but note that despite talk of NASA projects concerning near-Earth asteroids and lunar lagrange point 1, this next statement from Dr Ellen Stofan, Chief Scientist, NASA, and principal advisor to the NASA Administrator, fulfills that ‘don’t mention the Moon’ embargo.[25]

NASA’s focus now is on sending humans beyond low-Earth orbit to Mars. We are trying to develop the technologies to get there, it is actually a huge technological challenge. There are a couple of really big issues. For one thing – Radiation. Once you get outside the Earth’s magnetic field we are going to be exposing the astronauts to not just radiation coming from the Sun, but also to cosmic radiation. That's a higher dose than we think humans right now should really get. [emphasis added].

So if it is now considered that human beings 'right now' cannot cope – then nor could they 'back then' – and nor could NASA risk any Apollo astronauts becoming ill or dying either during or after the missions.[26]

As Dr Nathalie Cabrol of Ames Research Center and since January 2015, Principal Investigator of the SETI Institute NASA Astrobiology Institute (NAI) team remarked in September 2015:

'We are somewhat advanced, but we are a teenage civilisation. We are playing with toys and technologies but we don’t know the rules very well yet.’

Which is very true, whether applied to her specialist zones of interest or the state of rocket travel.

NASA Mars
Notice the subtle inference of looking for ET, with the Science, Exploration, Technology banding. SETI

Conclusion

The presentation of this Orion BIRD data, together with the difficulties over its publication infers that some within the space agency have noticed that the Apollo radiation data doesn’t fit the template. Therefore it's become necessary for NASA staff to spend hours writing statements full of obfuscations in a literary exercise of 'simple avoidance'. But no amount of careful massaging of descriptions of the space environment through crafted vocabulary and pretty pictures can hide the truth contained in the actual figures.

This BIRD Radiation Detector report seemingly confirms that the dosimetry radiation data for the manned Apollo lunar flights was collected while remaining in LEO. Whether deliberately or unwittingly, NASA's own data has blown apart the notion that a manned Apollo crew ever travelled to the Moon.

Mary Bennett

Aulis Online, October 2015


Footnotes

[1] Space radiation as the show-stopper for space exploration. Dark Moon: Apollo and the Whistle-Blowers, Aulis Publishers, 1999, Professor Clive Dyer Ch3.
Astronaut radiation exposure can be attributed to three major sources:
Galactic Cosmic Rays (GCR): GCRs consist of highly energetic nuclei of atoms from hydrogen to uranium and are present to some degree throughout the heliosphere regardless of orbit, and mass, or geomagnetic shielding. Translation: unstoppable, the quantity present, or occupancy dictating the level of danger for the spacecraft and its astronauts.
Solar Particle Events (SPE): SPEs consist primarily of protons of varying spectral characteristics (10s of MeV to a few GeV) and are usually highly-attenuated by mass and adequate geomagnetic shielding. Translation: these are most often, but not always, reduced in intensity but not entirely stopped.
Trapped Particles: Trapped particles consist of lower-energy electrons (maximum energy on the order of 10 MeV) and protons (maximum energy on the order of hundreds of MeV). They are a concern only in orbits around bodies with significant planetary magnetic fields, such as Earth. Translation: In the case of Earth, the Van Allen belts have to be safely traversed if going beyond LEO to the Moon, Mars or elsewhere.
http://www.convert-me.com/en/convert/radiation/
http://www.nrc.gov/reading-rm/basic-ref/glossary/rad-radiation-absorbed-dose.html
http://www.nrc.gov/reading-rm/basic-ref/glossary/ionizing-radiation.html
http://www.nrc.gov/about-nrc/radiation/health-effects/measuring-radiation.html

Radiation may be defined as energy in transit in the form of high-speed particles and electromagnetic waves. Electromagnetic radiation is very common in our everyday lives in the form visible light, radio and television waves, and microwaves. Radiation is divided into two categories – ionizing radiation and non-ionizing radiation.
Ionizing radiation is radiation with sufficient energy to remove electrons from the orbits of atoms resulting in charged particles, and it is this type of radiation that is evaluated for purposes of radiation protection. Examples of ionizing radiation include gamma rays, protons, and neutrons. Ionizing radiation is different from ion formation that occurs in ordinary chemical reactions, such as the generation of table salt from sodium and chlorine. In such a reaction, only the outermost electron is removed to form a positively charged ion. With ionizing radiation, if the energy is sufficient, electrons other than those in the outermost orbits can be released; this process renders the atom very unstable, and these ions are very chemically reactive.
Non-ionizing radiation is radiation without sufficient energy to remove electrons from their orbits. Examples are microwaves, radio waves, and visible light.
Space radiation consists primarily of ionizing radiation which exists in the form of high-energy, charged particles. There are three naturally-occurring sources of space radiation: trapped radiation, galactic cosmic radiation (GCR), and solar particle events (SPE).
What is space radiation? http://srag.jsc.nasa.gov/SpaceRadiation/What/What.cfm
Solar cycle: The Sun's activity is characterised by an 11-year cycle that can be divided into four inactive years (solar minimum) and seven active years (solar maximum). Changes in electromagnetic radiation, particles, and magnetic fields arriving from the Sun have a significant influence on the space surrounding the Earth. Events such as solar flares and coronal mass ejections, that increase during solar maximum, give rise to solar particle events and geomagnetic storms at the Earth.
Van Allen belts/VABs: Not all of the solar particles are deflected by the magnetosphere, and some become trapped in the Earth's magnetic field. The particles are contained in one of two doughnut-shaped magnetic rings surrounding the Earth, the Van Allen radiation belts. The inner belt contains a fairly stable population of protons with energies exceeding 10 MeV (mega electron volts). The outer belt contains mainly electrons with energies up to 10 MeV. The charged particles which compose the belts circulate along the Earth's magnetic lines of force. These lines of force extend from the area above the equator to the North pole, to the South Pole, and then circle back to the Equator.
South Atlantic Anomaly/SAA: Except for the Apollo missions*, NASA's manned spaceflight missions have stayed well below the altitude of the Van Allen belts. However, a part of the inner belt dips down to about 200 km into the upper region of the atmosphere over the southern Atlantic Ocean off he coast of Brazil. This region is known as the South Atlantic Anomaly. The dip results from the fact that the magnetic axis of the Earth is tilted approximately 11 degrees from the spin axis, and the center of the magnetic field is offset from the geographical center of the Earth by 280 miles. The largest fraction of the radiation exposure received during spaceflight missions has resulted from passage through the South Atlantic Anomaly. Low inclination flights typically traverse a portion of the South Atlantic Anomaly six or seven times a day.
[2] Orion: http://blogs.nasa.gov/orion/2014/11/
[3] Press Kit
http://www.nasa.gov/sites/default/files/files/orion_flight_test_press_kit(1).pdf
[4] http://www.spaceflight101.com/orion-eft-1-mission-updates.html
[5] Curiosity radiation findings on NASA’s Curiosity Cam of 30 May 2013, 7:24pm.
also http://www.sciencemag.org/content/340/6136/1031
[6] The Confusing World of Radiation Dosimetry M.A. Boyd, 2009.
http://www.wmsym.org/archives/2009/pdfs/9444.pdf
This paper starts by asserting that the US is out of step by almost 20 years with the International Commission for Radiological Protection’s (ICRP) recommendations for calculating the radiation dose to humans, and in some cases, 50 years behind the times. This problem was compounded by the fact, ‘that in the US, the measure of regulatory compliance for dose-based rules depends on which regulation is being enforced and which of the various systems of dosimetry is referenced in the rule’. In Boyd’s opinion ‘the absorbed dose – the amount of radiation energy deposited in a unit mass of tissue, is an inadequate surrogate for managing radiation risk because different types of radiation cause differing degrees of harm for the same amount of dose... ‘the equivalent dose is also an inadequate surrogate for assessing radiation risk, only accounting for differences in the different types of radiation (alpha, beta, gamma) to cause biological harm’.
Note: Given that the latest methodology for determining the effective dose of radiation to a human beings' organism was published as ICRP-103 in 2008 – that means that essentially some US departments are relying on standards first evaluated in 1958, when the VABS were first measured and the nuclear industry was underway. The ICRP have developed the BFO tables and the organs of the body are now number 15, with no specific mention for the eye – which is most surprising, as radiation is a major source of problems for astronauts eyes.
[7] Arthur Clarke quotes on lunar travel foot note Dark Moon op. cit. Ch 8.
[8] http://srag-nt.jsc.nasa.gov
[9] https://three.jsc.nasa.gov/articles/Turner.pdf
[10] Dark Moon op.cit. Operation Argus & Starfish Prime Ch 8.
[11] http://www.nasa.gov/mission_pages/rbsp/news/third-belt.html
[12] Orion GNC Mitigation efforts for Van Allen Radiation
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20130008930.pdf
Note the PDF itself is incorrectly titled as 20130008930mitigation efects for VABS Orion paper Ref 24.
[13] http://sibrel.com
[14] NASA technical report website NOT hosting the Orion radiation data http://ntrs.nasa.gov
[15] NASA website actually hosting the Orion radiation data
http://ston.jsc.nasa.gov/collections/trs/_techrep/TP-2015-218575.pdf
[16] Towards A Moon Base: Has anything been learned from Apollo? Phil Kouts, Aulis Online, 2015
[17] http://forum.nasaspaceflight.com/index.php?topic=29830.10;wap2
[18] http://www.aulis.com/mojave.htm
[19] http://www.michaelcrichton.com/america-beyond-challenger-disaster/
[20] http://srag.jsc.nasa.gov/Publications/TM104782/techmemo.htm#LOW
[21] RAM is Radiation Area Monitor. Continuous area monitoring is necessary because exposure rates and their distribution throughout the vehicles change with vehicle altitude, attitude, internal vehicle configuration, number and location of modules, the position in solar cycle, etc. Passive dosimeters are not affected by power loss to other Active Radiation Area Monitoring. Active radiation area monitors provide continuous information to ground controllers for tracking cumulative crew exposures during missions, identifying areas within the vehicle to avoid due to high dose rates, identifying low dose rate areas to use as 'storm shelters’, and alerting to enhanced radiation environment conditions.
The Radiation Area Monitor (RAM) is a small set of thermoluminescent detectors (TLD) encased in a Lexan holder. The material responds to radiation via electronic excitation states in the various TLD materials. After exposure, the amount of absorbed energy (dose) is determined by applying heat and measuring the amount of visible light released as these excited states are returned to equilibrium. RAMs are placed in throughout the volumes of both the ISS and the Space Shuttle; the ISS monitors are swapped out during the periodic Shuttle missions. The Crew Passive Dosimeter (CPD) is identical to the RAM and is carried by each member of the crew during the entire mission.
ISS Tissue Equivalent Proportional Counter:
The TEPC is designed to measure the dose that a small volume of tissue would receive from a wide variety of radiation sources. It simulates a 2µm diameter volume of tissue using a cylindrical detector design. The detector volume is 2 inches in diameter and 2 inches long, and is filled with a very low pressure of propane gas. The gas volume is surrounded by tissue equivalent plastic. The organic molecules in the plastic and gas effectively simulate the cell wall and cell body respectively. When radiation interacts with the detector, electrons are produced and accelerated towards a small wire in the middle of the detector that is held at a high positive voltage. As the electrons accelerate towards the wire, other electrons are created, and an amplification of the initial event occurs.
The electrons are collected by the wire and a signal pulse is generated that is proportional to the energy of the radiation that hit the detector. The signal pulses are then amplified and stored in memory in the spectrometer portion of the instrument until they are downloaded to the ground for detailed analysis. The spectrometer also performs real-time calculations and displays the average dose rate and other parameters on a small LCD screen on the instrument for use by the astronauts, and sends similar information to Mission Control that allows SRAG personnel to constantly monitor the radiation environment inside the spacecraft. The ISS TEPC also has an alarm capability that will inform the Crew and ground personnel if radiation levels exceed a predetermined threshold. The ISS TEPC is also designed to be portable so that it can be moved around inside the spacecraft and the radiation environment inside the vehicle can be mapped.
See [8] and
http://www.nasa.gov/mission_pages/station/research/experiments/TEPC.html#applications

[22] In 1973 NASA published a table of averaged dose absorbed rates for the thermoluminescent dosimeters on Apollo missions. Comparable with the RAM on Orion. In its report NASA noted that depending on what they were doing, where they were within the craft and the amount of shielding at any one location, individual dosimeter readings varied approximately 20% from the emission average – but forgot to say whether this 20% was less or more. It stated that doses to the BFO (Blood forming organs) were approximately 40% lower than the values measured at the body surface. Note that ‘skin’ is also used to define the external covering of a spacecraft. No individual readings have been published in the public domain and that dose equivalent for Apollo 14 measurement stated in units relative to the dose equivalent (now known as the effective dose) doesn't reflect the Q factor criteria established by the relevant authorities for estimating this effective dose. This term Q factor is now calculated as the weighting factor and consists of two parts. The BFO are also far more defined now than in the days of Apollo.
[23] The updated 2012 National Council of Radiation Protection and Measurements (NCRP) models predicts the upper 95% confidence for ISS mission radiation risk levels during solar minimum could exceed limits for cancer fatality by 18 months or 24 months for females and males, respectively. Also, the median Probability of Causation (PC) and upper 95% confidence intervals of PC values, are predicted to exceed 50% for several cancers during two or more ISS missions of 18 months or longer durations during solar minimum, or longer durations for other solar cycle phases. These results will be factored in for planning of 1-year ISS missions or Mars exploration missions.[6]
[24] Taking the daily dose rate of an Apollo flight dividing by 24 to find a dose rate per 60mins then multiplying this by either 4.25 (for those 249 mins spent outside the atmosphere) or by 4.5 (for those 270mins from launch to splashdown) produces a comparison with the Orion data in table 1. Apollo 7 orbiting in LEO with a perigee of 229 and an apogee of 309 miles, (the top end of the ISS comfort zone) gives 0.025mGy/249mins (0.028mGy/270mins) against ISS 0.015mGy/270mins. The Apollo 14 daily dose rate of 1.27mGy comes to 0.219mGy/249 min or 0.238mGy/270mins.
A NASA document from 2012 pg5 stipulates the terms for establishing the alarm levels on the ISS with a range of 0.02 mGy/min to 10 mGy/min. The 1mGY/min at 20 times the alarm level of the ISS quoted in the BIRD document relates to an alarm level of 0.05mGy/min.
[24] Dark Moon op.cit. Jodrell Bank’s Sir Bernard Lovell letter to authors on US and USSR attitudes towards radiation protection for astro-cosmonauts.
[25] BBC2 Newsnight interview, originally on BBC iPlayer, November 2014.
[26] Wernher von Braun comment to Neil Armstrong shortly before his death: "By the Prognosis of statisticians, you should be dead in space and I should be in jail." Dark Moon op.cit.Ch 9.



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