At the Right Place at the Right Time…

11 06 2014

Two BA-330 modules form Bigelow Aerospace's Alpha Station, with SpaceX's Dragon and Boeing's CST-100 depicted docked, (left and right, respectively). [Credit: Bigelow Aerospace]

Two BA-330 modules form Bigelow Aerospace’s Alpha Station, with SpaceX’s Dragon and Boeing’s CST-100 depicted docked, (left and right, respectively). [Credit: Bigelow Aerospace]

Finally.

On top of all of the other trouble I’ve been habitually getting myself into during the last several months, a series of unlikely and highly serendipitous events recently culminated in a sudden career shift.  -One that, I might add, I’ve been pressing for and gambling on for some time.

–And for longtime readers, it’s a shift that strikes to the very heart of this blog.  My unorthodox gambit toward the stars, it may appear, may have actually just paid off.

As of two weeks ago, I no longer make the daily drive to the deserted Nevada haunts of the former A.E.C..  Instead, I’m now under the employ of Bigelow Aerospace, LLC right here in Las Vegas(!).

There just aren’t powerful enough adjectives to describe how thrilling a development this has been for me.

(A Lack of) Details:

As a strictly private enterprise, security concerns regarding my activities at Bigelow Aerospace are paramount, so details I can reveal about my position and activities are consequently sparse.  However, I can say that my assignment as a Crew Systems Scientist in the Life Support Systems group, (in addition to serving as the company’s Assistant Radiation Safety Officer), presently has me diving into materials properties in the space radiation environment, with hints of larger project management responsibilities not far on the horizon…

I’ve never enjoyed work more in my life, and suddenly, it seems that everything has come full circle.

Looking Ahead

Growing up in Vegas, I have a deep attachment to the region.  That’s probably why I ended up moving back.  Meanwhile, my suspicion has long been (for a couple of decades, now) that aerospace is the cornerstone industry Southern Nevada has been waiting for and that our economy now so desperately needs.  (See: Assembly Joint Resolution #8, 1999, to learn about Spaceport Nevada and infer the crushing tale of the ahead-of-its-time initiative that might have changed the region as we know it…)  The synergy of Bigelow Aerospace’s location here, the company’s globally-unique, NASA-derived and improved spacecraft technology, and their recent sale of a module to the International Space Station is highly coincidental.

I feel it in my bones that it’s not only Southern Nevada’s legacy, (e.g., NASA Apollo training, NASA-AEC NERVA nuclear rocket program), but it’s Southern Nevada’s destiny to become an aerospace nexus.

Let’s see if I can’t do something about it.

Semper Exploro!

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System of Fear: A Dose of Radiation Reality

14 10 2013

In line with last week’s post, please see the below infographic, which paints radiation doses in the visual context of a sort of system of planets according to size (click to enlarge):

SystemofFearI

As is plainly evident, it’s shocking how much the public perception of radiation doses and negative health effects differs from reality.

(For example, in today’s perceptual climate, who would believe that a person could live within a mile of a nuclear powerplant for a thousand years before receiving the radiation dose from a single medical CT scan?)

If feedback to this is positive, I think I’ll make this the first in a series of similar infographics.  (Perhaps people would find it interesting/useful to next have illustrated the relative magnitudes of nuclear disasters?)

_______________________________________________

If anyone doubts the numbers in the above diagram, please feel free to investigate the references for yourselves!

International Atomic Energy Agency:
http://www.iaea.org/Publications/Factsheets/English/radlife.html

U.S. Environmental Protection Agency:
http://www.epa.gov/radiation/understand/perspective.html

U.S. Nuclear Regulatory Commission:
http://www.nrc.gov/about-nrc/radiation/around-us/doses-daily-lives.html

U.S. National Council on Radiological Protection (via the Health Physics Society):
http://hps.org/documents/environmental_radiation_fact_sheet.pdf

U.S. Department of Energy:
http://lowdose.energy.gov/faqs.aspx#05





Nuclear and Atomic Radiation Concepts Pictographically Demystified

10 10 2013

Greetings, all.  Today I’m attempting a different, largely pictographic approach to demystifying the concept of “radiation” for the layperson.

Despite the hype, radiation is a natural part of our planet’s, solar system’s, and galaxy’s environment, and one that our biology is equipped to mitigate at ordinary intensities.  It’s all actually surprisingly straightforward.

So, without further ado, here goes – a post in two parts…

PART I – Radiation and Radioactivity Explained in 60 Seconds:

The Atom

This is a generic diagram of the atom, which in various combinations of the same bits and parts is the basic unique building block of all matter in the universe:

Atom_Labels

This somewhat simplified view of an atom is what makes up the classic “atomic” symbol that most of us were exposed to at the very least in high school.

Radioactive Atoms

However, what is almost never explained in school is that each atomic element comes in different versions – slimmer ones and fatter ones.  When an atom’s core gets too large, either naturally or artificially, it starts to radiate bits of itself away in order to “slim down.”  This is called being radio-active.

So, there’s nothing to “radiation” that we all haven’t been introduced to in school.  Radiation is the name given to familiar bits of atoms (electrons, protons, neutrons) or beams of light when they’re being flung away by an element trying desperately to squeeze into last year’s jeans… metaphorically-speaking, of course.

Here is a diagram illustrating this process.  (Relax! – this is the most complicated-looking diagram in this post):

RadioactiveAtom_Radiation_Labels

So, when a radioactive element has radiated enough of itself away and is no longer too large, it is no longer radioactive.  (We say it has “decayed.”)

That’s it!

That’s as complicated as the essential principles of radiation and radioactivity get.  It’s just basic chemistry that isn’t covered in high school, (though in my opinion it should be!).

PART II – Take-Home Radiation Infographics

So, in an effort to help arm you against the rampant misinformation out there, here is a collection of simple diagrams explaining what everyone out there seems to get wrong.  (Feel free to promote and/or distribute with attribution!)

First, what’s the deal with “atomic” energy/radiation versus “nuclear” energy/radiation?  Do they mean the same thing?  Do they not?  Here’s the skinny:

AtomicvsNuclear_labels

That’s all.  “Nuclear” means you’ve zeroed in on an atom’s core, whereas “atomic” means you’re talking about something dealing with whole atoms.  No big mystery there.

Next, here is a simple diagram explaining the three terms used to describe radiation that are commonly misused in the media, presented clearly (click to enlarge):

MisusedTerms_labels

(Armed with this, you should be able to see why saying something like, “The radiation is releasing contamination!” doesn’t make a lick of sense.)

Now, here is a diagram explaining the natural sources of radiation we’re exposed to everyday on planet Earth:

RadiationNaturalSources_labels

And here are the basic principles of radiation safety, all on one, clean diagram (click to enlarge):

RadiationSafetyv2_labels

The End! 

Despite the time and effort spent socially (politically?) promoting an obscured view of this science (or so it seems), there is nothing more mysterious about radiation than what you see here.

Please feel free to contact me with any questions, and remember:  We have nothing to fear but fear itself!

Semper Exploro!





Treatise: Abandoning OldSpace’s Conceit

30 07 2013
Should this be considered space exploration?  "Pilot Felix Baumgartner jumps out from the capsule during the final manned flight for Red Bull Stratos in Roswell, New Mexico, USA on October 14, 2012." (Credit: Red Bull Stratos)

Should this be considered space exploration? “Pilot Felix Baumgartner jumps out from the capsule at 126,720 feet during the final manned flight for Red Bull Stratos in Roswell, New Mexico” (Credit: Red Bull Stratos)

Space Exploration is suffering an identity crisis.

Like atmospheric flight before it, space exploration is evolving to include a spectrum of public and private participants, motivations, and goals.  However, even amongst space enthusiasts and professionals, there is much (mostly friendly – I’ll get to that) debate regarding just what exactly it is that qualifies as worthy space exploration.

This debate tends to set itself up in terms of convenient binaries:

Human or robotic?  Public or commercial?  Lunar or Martian?  To seek out an asteroid where it orbits or capture one and bring it back to us?  (There are many more…)

Determining who or what is qualified (or makes someone qualified) to wear the title of “astronaut” and engage in space exploration seems to be the source of much of any contention amongst engaged parties.  And, in certain corners, the resulting conversation tempestuously swirls around whether or not some current private efforts to reach space even qualify as exploration at all.

With this in mind, and before the conceptual landscape becomes any more confusing or inconsistent, let’s take a detailed journey through the convoluted and fascinating history of just what it means to explore space and – not always coincidentally – to be considered a space explorer.

In this way, a new appreciation of the promise and potential of so-called NewSpace activities might be produced – one that thwarts brewing, (and in my opinion, shortsighted), negative bias amongst those in the established space exploration community…

Apollo 17 Lunar Module cabin interior after day 3 on the lunar surface: Helmets and space suits on the engine cover at left with Astronaut Gene Cernan looking on.  (Credit: NASA)

Apollo 17 Lunar Module cabin interior after day 3 on the lunar surface (12/13/72): Helmets and space suits piled on the engine cover with astronaut Gene Cernan at right. (Credit: NASA)

Deconstruction of the Space Explorer

It used to be considered that human beings had to bodily participate, a la the Lewis and Clark Expedition, in order for something to be considered “exploration.”  In this light, robotic space missions were once seen only as tantalizing forerunners to the delivery of human bootprints, when the real exploration began.

Now, however, based in part on funding, politics, and the march of technology, the robots have claimed much of the exploration center stage as competent cosmic surveyors, jaw-dropping photographers, and even mobile geologic laboratories.

While not autonomous, their successes have led many to seriously question whether human beings will ultimately have a primary role in space exploration, if any significant role at all.

Meanwhile, those who still endorse human ingenuity and adaptability as key components for space exploration face a simultaneous conceptual quandry.  Once something clearly defined in nationalistic terms, (and intentionally invoking, let’s be honest, Greek-demigod-like associations), the conceptual waters of the 21st century human space explorer have also been permanently muddied.

jsc2006e40638

Spaceflight participant Anousheh Ansari prior to her launch to the Int’l Space Station aboard a Soyuz spacecraft, 11/’06. (Credit: NASA)

Anyone who crosses the invisible and somewhat arbitrary 62-mile altitude line to “outer space” can be honestly called an “astronaut.”  However, a healthy handful of space tourists are now included in the fold of human beings who have crossed the threshold to space to become astronauts.  To make the landscape even more confusing, many have advised (NASA included) that out of respect and/or accuracy we should refer to these self-funded astronauts as “spaceflight participants,” not tourists.

So, are these participants to be considered explorers in their own right even if they are not considered career astronauts?  Or are they simple sightseers along for the ride with the true explorers?

Is or can there be a difference between a spaceflight participant and a tourist or sightseer?

Astronaut-Explorer: Still Synonymous?

Whatever the semantics dictate, with hundreds of additional, willing, and self-funded future astronauts waiting in the wings, it is reasonable to ask whether or not being an “astronaut” even implies space exploration anymore.

Is it the intent of the trip or tasks to be performed that is or are the key distinguishing factors between thrill-seeking and exploration, (i.e., is science to be performed)?  This might be a sensible definition, yet in asking this question it is noteworthy to point out that many of the astronaut-spaceflight-participants have performed scientific work while in space.

Despite this fact, many in the what I like to call the “OldSpace” community, (namely current or former NASA employees and contractors with a more traditional view of space exploration), balk at the idea that these participants represent legitimate space exploration.  This seems to imply that it is only professional astronauts that are to be considered the explorers.

However, the logic of making such a distinction quickly falls apart when considering the countless private expeditions throughout human history that have opened continents, frontiers, and knowledge to human awareness.

So, this is my first point.  We’re woefully vague when it comes to describing those who travel to or work in space.

Peering more deeply into the issue, one of the primary issues is the qualification of someone to become an astronaut.  Right now, by strict definition all it takes is a suitable increase in altitude for someone to earn their astronaut wings.

Is this an accurate or meaningful way to define an astronaut in the first place?  (Or do we need a new or different definition altogether?)

The nose of the Gemini-9A spacecraft over the Pacific Ocean during the second spacewalk in NASA history, on 5 June 1966.  (Credit: NASA)

The nose of the Gemini-9A spacecraft over the Pacific Ocean during the second spacewalk in NASA history, on 5 June 1966. (Credit: NASA)

Where is Space, Anyway?

Like a poorly-woven sweater, the more one pulls on this thread of questioning, the faster the whole thing unravels.  Consequently, it may be here that we find the clearest junction from which the many different views of space exploration begin to diverge.

Classically, “outer space” is considered the region encompassing the rest of the universe beyond the Earth’s atmosphere.  That’s simple enough.

However, we now know that the most rarefied portions of the Earth’s atmosphere (exosphere) extend out to more than 62,000 miles away from the Earth’s surface(!), while the more conventional uppermost portions of the atmosphere extend to 200-500 miles in altitude (thermosphere).  Yet at all of these fringe heights, the atmosphere is still little more than individual atoms zipping around a vacuum, separated from one another by so great a distance that they are practically indistinguishable from outer space.

To make matters more impractical, these altitudes vary by several hundred miles depending on how much solar activity is warming up the atmosphere at the time.

Expedition7EarthAtmosphere

View of Earth’s horizon as the sun sets over the Pacific Ocean as seen from the Int’l Space Station. (Credit: NASA)

So, where do we draw that magic line separating atmosphere from space?  Let’s take a look at the reality from the ground up ourselves (so-to-speak),  and you can decide whether or not you would have placed the dividing line to “space” where current convention has drawn it:

  1. Humans can generally function well without supplemental oxygen to an altitude of roughly two miles above sea level, or 10,000 feet.  I don’t believe any reasonable argument can be made that any region located hereabouts represents “outer space.”
  2. However, by the time one reaches little more than three times that, (at 36,000 feet, or 7 miles in altitude – the cruising flight altitude of most commercial airline traffic), not only would a would-be explorer require supplemental oxygen, be he or she has (surprisingly) already emerged from three-quarters of the bulk of the Earth’s atmosphere.  (That’s 75% of the way to space by mass!)
  3. By the time one reaches 12 miles in altitude or about 62,000 feet, (a.k.a., the Armstrong Line), In addition to oxygen, a pressure suit is absolutely required in order to prevent the moisture in one’s mouth, throat and lungs from boiling away due to the low pressure.  (Sounds awfully space-y.  Are we there, yet?)
  4. The atmospheric layer known as the stratosphere extends upwards to 170,000 feet, or 32 miles, and contains the planet’s ozone layer.  This is now a height that is above all but rarest, upper-atmospheric clouds.
  5. From there to roughly 50 miles (264,000 feet) is the Earth’s mesosphere, the region of the atmosphere where most meteors burn up upon entry due to friction with the atmosphere.  (Does the fact that meteors really encounter the atmosphere here mean that this is the real boundary to space?  Or are we already there?)
  6. The thermosphere extends from there to an average of 300 miles (1,584,000 feet) in altitude, where atoms in the atmosphere can travel for the better part of a mile before running into one-another.  The International Space Station is located within this layer, and I don’t think anyone would argue that we’re now definitely in “outer space.”

Where would you put the dividing line?

Current international convention, known as the “Kármán Line,” places it at 62 miles in altitude, or roughly 330,000 feet.  That’s out of the mesosphere and just peeking into the thermosphere.

Confusingly, however, (and perhaps unsurprisingly after reading the above), the U.S. has separately defined an astronaut as anyone who reaches an altitude greater than 50 miles, or 264,000 feet, in altitude.

Captain Joe Engle is seen here next to the X-15-2 rocket-powered research aircraft after a flight. Three of Engle's 16 X-15 flights were above 50 miles, qualifying him for astronaut wings under the Air Force definition.  Engle was later selected as a NASA astronaut in 1966, making him the only person who was already an astronaut before being selected as a NASA astronaut. (Credit: NASA)

Captain Joe Engle, a living example of the inconsistency surrounding use of the term “astronaut,” standing next to the X-15 research rocketplane. Three of Engle’s sixteen X-15 flights were above 50 miles, qualifying him for astronaut wings under the Air Force definition, and Engle was later selected as a NASA astronaut in 1966. This makes him the only person in history who was technically already an astronaut before being hired as a NASA astronaut. (Credit: NASA)

Been There, Flown That?

According to current convention, one needs to cross either 50 or 62 miles in altitude to reach space.  Yet the above altitude list demonstrates that what most would refer to as a spacesuit (a pressure suit) is required by anyone attempting even 1/5th that altitude.

Clearly, walking through the above exercise demonstrates that the human experience of “outer space” is reached far lower in altitude than these conventions currently dictate.  Further, it’s clear to see that a would-be astronaut has escaped more than 90% of the atmosphere by mass well before reaching the Kármán Line.

(To reiterate, this is a rub even between the U.S. and international bodies, whose definitions of the dividing line to space differ by more than 63,000 feet!).

Hence, this is where serious debates about space exploration begin.  For example, when private spacecraft aim to achieve suborbital spaceflight altitudes of 40 miles, such as XCOR Aerospace’s Lynx Mark I, they do not currently break through either the U.S. space line or the Kármán Line.  Consequently, any passengers aboard cannot be technically called “Astronauts” by the most generally-accepted definition of the term.

13-02-13_lynx-hotfire-5885-mod

XCOR XR-5K18 “Lynx” main engine test on the flight weight fuselage. The Lynx Mark I is designed to achieve an altitude of 200,000 feet, or roughly 40 miles. (Credit: XCOR Aerospace)

However, as anyone can see in the above list of altitudes and physical characteristics, 40 miles above Earth not only has long achieved the human experience of “space,” but it skirts the boundary above which even meteors pass by at many tens of kilometers per second (where entry friction would make even a sparse but significant atmosphere quickly known) without noticing anything appreciable.

Outer space, indeed!

However, particularly, from the OldSpace corner, I’ve personally detected the prevalent sentiment that since this sort of travel doesn’t even reach “space,” it therefore could not possibly be considered exploration, much less fruitful exploration.  Even those private efforts that do breach the Kármán Line are often scoffed at as repeats of old triumphs and rejected under nearly the same pretense.

So, in an effort to thwart what I see as burgeoning (and perhaps  unconscious) resentment within the more traditional segments of the space establishment with respect to new, private space technology, projects, and the human travelers that will utilize them, let’s delve further toward the heart of this identity crisis.

While the advent of space tourism (or participant-ism) began in the early 2000s, it is with one specific event that to my heuristic eye the socio-technical deconstruction of our once-clean concept of the human space explorer truly began:

The 2004 clinching of the Ansari X Prize by the private flights of Virgin Galactic‘s SpaceShipOne.

SpaceShipOne released from the White Knight mothership beneath a crescent moon. (Credit: Scaled Composites/SpaceDaily)

SpaceShipOne released from the White Knight mothership beneath a crescent moon. (Credit: Scaled Composites/SpaceDaily)

Suborbital: Not Space Enough?

Objectors to the idea that spaceflights like that performed by SpaceShipOne can be considered fruitful space exploration point out that SpaceShipOne was only a suborbital spaceplane, boasting speeds far less than those required to reach orbital velocity.

(Translation:  Suborbital spacecraft only have enough steam to peek out into officially-defined space for a few minutes before falling back to Earth.  In contrast, bigger spacecraft, like NASA’s former Space Shuttle or SpaceX’s Dragon, can power all the way up to orbital speed and remain in space until they choose to slow down and fall back to Earth or are slowly brought down by atoms in the sparse upper-atmosphere.)

Further, these objectors often and rightfully point out that these very low-altitude portions of outer space, referred to collectively as “suborbital space,” have already been traversed hundreds of times by astronauts.  (Indeed, more than 250 times during the Space Shuttle Program alone.)

SpaceShipOne’s achievement itself was a modern replication of the 1960s’ X-15 Program, the pioneer rocketplane that produced the world’s first astronauts and gathered invaluable research for NASA’s Mercury, Gemini, Apollo, and Space Shuttle programs.

Hence, arguments against the concept of private suborbital space exploration typically conclude that, with all of this in mind, there’s no more exploration to suborbital spaceflight than driving down a paved road.  Suborbital spaceflight participants are therefore not explorers, nor can what they engage in while there be called space exploration.

Particularly amongst the old guard of space science, “exploration” is therefore reserved for those pushing the frontier in higher orbits, cislunar space, trips to near-Earth asteroids, Mars, and beyond.

Astronaut pilots Brian Binnie (left) and Mike Melvill helped Burt Rutan win the $10 million Ansari X Prize by completing two manned space flights within two weeks, each piloting SS1.  (Credit: Virgin Galactic)

Astronaut pilots Brian Binnie (left) and Mike Melvill. (Credit: Virgin Galactic)

However, before throwing in the towel on 21st century suborbital space exploration, we must address the reality that SpaceShipOne managed to privately achieve what until that time had only been accomplished by global superpowers – no small feat!  Further, it was a feat that led the FAA to award the first (and so far, the only) commercial astronaut spaceflight wings to pilots Brian Binnie and Mike Melvill.

Surely they can therefore be considered pioneers, and exploration seems a fitting term for their achievement.

Peeling the veil farther back, it’s true that so-called space tourists began purchasing trips to the Mir space station and then to the International Space Station as far back as 2001.  In order to participate, these private space adventurers had to endure and successfully complete the very same training as their Russian cosmonaut counterparts.

The intriguing question that follows is this: If what government-sponsored astronauts were engaged in was and is considered to be legitimate exploration, wouldn’t by extension the same label apply to all on the same voyage assisting in the same work?  If someone were to have purchased their way aboard Shackleton’s Endurance, would they be considered any less an explorer today?

Of course not.

Then, what of our oceans as a parallel?  They have been traversed hundreds of thousands if not millions of times in the last several centuries.  Does this mean that no exploration may be conducted on the Earth’s oceans in the 21st century?

Surely not.  Context is key.  (One may explore climate effects, seek out undiscovered ecological niches, probe poorly-mapped coastlines, explore archaeological evidence of our past activities, wield new technology to tease new data from an old environment, and that’s not even scratching the ocean’s subsurface…)

Just so, objections to suborbital spaceflight as legitimate space exploration logically fall apart.  In even greater degree than with Earth’s oceans, there is ample room and conceptual research justifications for the legitimate continued exploration of suborbital space.

So what’s the real issue here?  Why is there any resistance at all?

Evolution.

Or, more specifically, how we as a culture always tend to get evolution wrong.

An evolutionary path of spaceflight depicted.  (Credit: Virgin Galactic)

A depicted evolutionary path of spaceflight. (Credit: Virgin Galactic)

Getting Evolution Wrong, or

“How I Learned to Stop Worrying and Love NewSpace”

As a geologist, I’ve become very sensitive to a sort of teleological conceit that people tend to carry into the common understanding of biological evolution.  In other words, people tend to incorrectly believe that life evolves toward something.

We culturally call something that is more advanced more evolved, and we characterize something unsophisticated to be less evolved or primitive.  When something loses ground, we even say that it has devolved.

Well, much as the term “theory” is almost universally misused compared to the scientific meaning of the term, (people usually mean that they have a “hypothesis” when they say they have a “theory”), the terms “evolved” and “primitive” are fairly universally misused and misunderstood.

They’re relative terms, not universal terms.

One could paraphrase this misunderstanding by assessing the belief that there was a sort of biological, evolutionary destiny for algae – that given enough time and opportunity, the little, green “organism that could” would eventually evolve to become a human being.

This, in turn, reasonably translates to a belief that we as humans are more “advanced” than algae, and that we’re therefore “better” than algae.

One of the International Space Station solar arrays, which converts sunlight to energy.  (Credit: NASA)

One of the International Space Station solar arrays, which converts sunlight to energy. (Credit: NASA)

Many are consequently shocked to learn that all of these beliefs are untrue, based on a series of logical fallacies.  Science, quite surprisingly, shows us that quite the opposite is true.  Life will evolve in any number of convenient directions, even those that seem backwards to our modern perceptions.

Yes, human beings benefit from large brains, acute stereoscopic vision, and an uncanny ability to communicate, which we have wielded to our great advantage.  Algae cells possess none of these tools.  However, algae can convert sunlight into sugar using only a modest supply of water and carbon dioxide.  Our best attempts to use our “advanced” brains to perform this very same and ancient task have failed to come within even a fraction of li’l algae’s efficiency.  (Would that human beings achieve this apparently “primitive” feat, the human civilization would have permanently solved the social issues of hunger and starvation!  …That’s fairly “advanced” biological processing, if you asked me.)

So, by which yardstick are we to define “advanced”?  Conceit leads us to select our own attributes as more advanced, yet this is not scientific.  It’s arbitrary.

For a more specific example, the fossil record reveals in several instances that seaborne life, adapting to a changing and increasingly food-rich land surface, eventually (over the course of thousands or tens of thousands of generations) made feet of fins and took hold on land.  However, this same land-based life, under reverse pressure for food back toward the sea, over time reversed the trend and converted its feet back to fins once again.

The erroneous interpretation here, (like assuming that we’re more advanced than algae), is that feet are more advanced than fins.  The reality is that they are simply different biological tools that may be used, abandoned, and returned to if necessary or useful.

“More evolved” simply tracks the progression of evolution forward through time, whereas “more primitive” describes a rung in an organism’s ancestry.

(It is perfectly reasonable, then, in the reverse-adaptation scenario mentioned above, to have a situation where fins are more evolved than feet!)

In short, we see that instead of propelling itself toward a single destiny, life is flexible.  It responds to the pressures of the outside world, wherever they lead.  Evolution, therefore, is not so much the story of the noble rise of algae to one day become more “advanced” animal life to one day become even more advanced human beings who might one day build rockets to explore the stars…  Instead, biological evolution is a complex, daunting, nonlinear story of life surviving at any cost; adapting to any niche it can, and capitalizing to its fullest on whatever biological skills were close at hand.

So, too, is the same error present with our perception of spaceflight and space exploration.  As a modern, parasitic sort of conceit tagging along with our understanding of space history, we presume a linear destiny has been in play, when in fact it has not.

The original image above, a logo occasionally promoted by Virgin Galactic, intentionally relates evolution to spaceflight.  Ironically, it plays to both the incorrect and correct views of evolution.

People tend to view space exploration itself as a teleological journey toward more distant and exotic locations, describing it in apropos biological terminology as a migration of life toward a destiny amongst the stars, to new colonies, etc.

MarchofProgressThis is a feeling certainly visually-evoked by the above image of evolving spacecraft, a nod to the famous “March of Progress” illustration of 1965 simplified at right.  However, this view relies on the conceit that farther distances are more advanced or “better” than short-range flights.  When looking at the facts, this simply isn’t the case.

For instance, a phone in a pilot’s pocket aboard SpaceShipOne would have had literally thousands of times the computing power of the Apollo Lunar Module (LM) guidance computer, (to say nothing of SpaceShipOne’s onboard instrumentation).  SpaceShipOne, also leveraging new developments in the technology of aerodynamics, composite materials, GPS location and tracking, and with the novel innovation of a feathered wing configuration for reentry, was a much more technologically-advanced spacecraft than the LM.

The LM, it is also true to say, could not possibly have successfully produced aerodynamic lift or had enough thrust to land on the Earth, two feats SpaceShipOne performed with apparent ease.  But SpaceShipOne only poked its head out into space, whereas the LM both landed on and departed from the moon while enabling its passengers to perform extra-vehicular activities – all impossible feats for SpaceShipOne.

So, by which yardstick do we define “advanced”?  Here, our same algae/human conceit rears its head.  But clearly, destination and the level of technological advancement of a spacecraft are not related.  They are simply different.

In fact, looking more closely at the above diagram, this truth is actually captured.  An observer will note that the second to the last, most “evolved” spacecraft is actually the LM.  The final step in the sequence is SpaceShipOne, a ship whose maximum designed altitude does not come within 0.03% of the distance to the Moon.

It is this conceit, I believe, that is also at the heart of OldSpace’s reluctance to (or perhaps even resentment of) embracing private space exploration efforts and those who engage in them as space explorers.  We don’t like the messy version of evolution.

We prefer our teleology.

070326_bigelowview_hmed_10a.grid-6x2

Bigelow Aerospace’s Genesis 1 orbital module, a first-of-its-kind inflatable spacecraft boasting superior micrometeorite resistance than rigid modules. (Credit: Bigelow Aerospace)

Evolving Our View of Space Exploration

In almost back-to-back recent events, what to me is an example of the true nature of the conflict between the many colliding conceptions of astronauts, space explorers, and space exploration was brought into sharp relief:

On the one hand, a NASA historian who I greatly respect alleged to me that private suborbital spaceflight and even new, commercial orbital space modules and transportation systems (which have recently received NASA funding to enhance the U.S. space infrastructure and give scientists more platforms and opportunities to conduct research),  were patently unworthy of NASA dollars.

Existing Russian and U.S. systems should be relied upon, and the already pinched NASA budget, he implied, should be saved and consolidated for the more worthy endeavor of exploring truly uncharted planetary territory.

Would I ever argue against probing the possible subsurface seas of Europa, the lakes of Titan or even the permafrost-spiked upper latitudes of Mars as worthy exploration?  Certainly not.  I became a geologist for precisely these sorts of explorations.

However, this bias once again recalls our comfortable teleological conceit.

Nearly simultaneously with this conversation, I gave a talk at the 2013 Next-Generation Suborbital Researchers Conference where I championed the use of suborbital flights to gather new information to explore how low-dose, high intensity radiation exposures may affect the human body.  This untapped research, in turn, could help guide and revise radiation safety measures and protocols right here on Earth.

Admittedly, such work is not as thrilling or romantic as forging ahead into the uncharted lands of new worlds.  However, I would argue to the teeth that this research also presents a completely legitimate form of space exploration, one with potentially even more immediate application to life at home than exploring other worlds.

Likewise, expending the effort to create a private, orbital space transportation system may not seem to be breakthrough space exploration work.  However, the simple addition of more players, minds, and motives has the very real possibility of producing quantum leaps – at the very least by assaulting the status quo.  (On that note, keep an eye on SpaceX’s Grasshopper test program…)

This exemplifies what I see as the root of OldSpace’s resistance: The idea that ground already trodden has nothing left to teach us; That if it has been done before, especially by the hallowed pioneers of early NASA, it cannot be improved or expanded upon while possessing a legitimate claim to space exploration.

If this conception is as prevalent as it seems to me to be, it is with no small amount of urgency that we must confront this bias head-on.

Chiefly, such a perception amongst researchers and professionals in existing aerospace firms creates an entry barrier so impenetrable that private space exploration firms and the innovation that comes with them would be thwarted before they even had a chance to prove themselves in the space market.

Secondly, even if unwittingly held by those on grant review panels, in academic positions of leadership, or even in elected office, these perceptions would threaten the ability for new ideas, techniques, and novel research to receive the support they need to see the light of day, to the detriment of us all.

Like an accurate view of biological adaptation over time, we should afford our cherished concepts of space exploration the freedom to evolve with the pressures of the modern era.

The history of NASA spin-off technologies shows us that even one of these space-based innovations, which may not initially seem as teleologically-advanced as setting foot on Mars, may radically change life on Earth for the better.

Another, seemingly innocuous line of research explored in even the nearest atmospheric shores of so-called Outer Space could trigger the long-sought paradigm shift that at last transforms humanity into a thriving, spacefaring civilization.

Private, professional scientists preparing for hypobaric chamber astronaut training.  (Credit: Ben McGee)

Private, professional scientists preparing for hypobaric chamber astronaut training. (Credit: Ben McGee)

Reconstructing Space

When undergoing suborbital scientist astronaut training myself, a journalist for Newsweek who was there to chronicle the three-day training experience remarked something to the effect of, “People want to go to space because space is special, and the people who go there are therefore special.  So, isn’t it a problem that the more people go to space, the less special it all becomes, and fewer people will ultimately want to go or be interested in/by space?”

Essentially, he was wondering if our work to make space more accessible to both citizens and researchers wasn’t ultimately self-defeating.  It’s a fair question.

However, is that really what draws people to space?  Is it really simply the remoteness of outer space and a desire for the prestige associated with having been where so few have gone before?

Frankly, while I can’t speak for anyone but myself, this seems like the perception of someone who does not personally wish to engage in space exploration.  Of all the people I have known who wish to loose the bonds of gravity and touch the great beyond, it isn’t for bragging rights.

Instead, it’s a deeply personal calling – like those drawn to deep-sea or antarctic ice shelf research – something that seems to draw like-minded or like-willed people to the science frontiers to plunge their own hands past the realm of comfort and viscerally shove on the limits of knowledge and human experience.

By my internal compass, this is what separates mere sightseeing from honest exploration.  Bragging rights versus knowledge.

Adventure may be experienced in either case, but only in the context of the latter could a successfully-completed spaceflight ever be considered a failure, (e.g., if the experiment wasn’t successfully performed or a data-logger malfunctioned, etc.).  This is a healthy benchmark for an explorer, which becomes comfortably similar to how we define exploration here on Earth.

From this perspective, it finally occurred to me what it is that we really need in order to resolve these ongoing debates about space exploration and worthiness.  Quite simply, in order to allow space exploration to blossom, we must let space itself evolve…

…Our collective conception of space and astronauts, that is.

Pilot Felix Baumgartner jumps out from the capsule at an altitude of 24+ miles during the final manned flight for Red Bull Stratos, 10/14/12. (Credit: Jay Nemeth)

Pilot Felix Baumgartner jumps out from the capsule at an altitude of 24+ miles during the final manned balloon flight for Red Bull Stratos, 10/14/12. (Credit: Jay Nemeth)

Closing Thoughts

No matter where we determine the arbitrary dividing line separating the atmosphere from space to be, and irrespective of the motives of those who desire to travel there, the reality is that space is no longer an abstract location.  It’s a place.

In fact, “space” is many places.

Space includes suborbital space, near-space, low Earth orbit, the International Space Station, geosynchronous orbit, cislunar space, the Moon, Mars, asteroids, and all other natural and artificial celestial locales and bodies that now more than ever beg us to recognize them for what they are and pursue what they each, separately, have to teach us.

In so vast a series of environments, both literally and conceptually, there is ample room for all types of exploration, from the public and pure-science motivated to private and profit-oriented; From testing the farthest, uncharted reaches of deep space to surveying the near-space regions just beyond our atmosphere about which we have so much yet to learn, (take the recent discovery of upper-atmospheric sprites and elves as an example).

Just as the same, cerulean blue oceans beckon tourists to cruise in luxury within giant floating hotels, lure fishermen away from land to harvest food from the sea for both business and pleasure, and attract scientists to study its biological, geological, and climatological mysteries, so too will space invite a spectrum of sightseers, explorers, workers, and businessmen.

Consequently, I endorse an extremely broad and inclusive view of space exploration.  For example, while only half-way to even the most liberal current altitude line for reaching space, the Red Bull Stratos “space jump” served several significant space exploration research functions.

Specifically, in addition to wearing the trappings of spaceflight (i.e., pressure suit, pressurized capsule), the jump collected data invaluable to those currently modeling suborbital spacecraft passenger ejection systems, scenarios, and high-altitude parachute systems.  Likewise, prior to the jump (which broke several records), medical and physiological science had no idea what the effects of bodily crossing the sound barrier would be(!).

Further, I believe time will show that, long after our lingering 20th century biases have fallen away, legitimate exploration of all realms applicable to space exploration will be perfectly justified and therefore persistently embraced as such.

And in that case, exploration of each of these different regions of space and near-space will remain vibrant until the boundaries of our knowledge have been pushed so far outward that our civilization’s use of space makes it simply unrecognizable to us today.

It is then, perhaps, that space exploration will finally have abandoned our conceptual conceits and eliminated the vagueness of our young descriptions of the realms beyond our world and those who choose to work and explore there.

-And from the general term Astronaut-explorer I expect a new range of titles will have descended:  Astrographer, Stratobiologist, Orbital Engineer, Suborbital Astronomer, Selenologist, Areologist…

________________

Comments welcome.





Talking Space Radiation Dosimetry at NSRC 2013

24 06 2013
Having an unashamedly good time stealing a few moments between talks inside the XCor Lynx spacecraft mockup parked behind NSRC 2013.

Having an unashamedly good time stealing a few moments between talks inside the XCor Lynx spacecraft mockup parked behind NSRC 2013.

I recently had the great pleasure to give a talk (and serve as co-author for a second) at the fourth annual Next Generation Suborbital Researchers Conference (NSRC), held this year in Boulder, Colorado.

As a one-of-a-kind collection of researchers, entrepreneurs, spacecraft providers, students, and government representatives, NSRC’s intent is to foster collaboration of a sort that will enable the research world to fully utilize what amount to a fleet of new spacecraft looking to come online within the next 24 months.  In all, exciting to be amongst like-minded folks, great to see familiar faces again, and a thrill to forge new alliances.

Two Radiation Take-Homes for the Suborbital Space Community

IMG_4535So, what was I doing there?  In brief, on behalf of my spaceflight consulting firm, Astrowright, I made a daring and ill-advised attempt to shove a 40-slide presentation into 10 minutes, with (based on positive feedback) it seems at least a small amount of success.  (I wouldn’t have even made such a blitzkrieg attempt unless it was absolutely necessary in the context of my talk.)

The intent?  To give a broad enough overview of radiation detector theory so that I had a prayer of communicating to this very select audience two imminent realities of space radiation dosimetry:

  1. The private/commercial spaceflight world, particularly in the suborbital context, is primed to (mis)use off-the-shelf radiation dosimeters designed for the commercial nuclear world; these instruments will not deliver complete or ultimately meaningful numbers without applying specific scaling algorithms to the results, in essence calibrating them for the space environment.  User beware!
  2. The greatest benefit of bothering to outfit suborbital astronauts with radiation dosimeters might not be to the spaceflight participants themselves, (who would receive in all but the most extraordinary circumstances a practically immeasurable radiation dose).  Instead, the greatest effect may be to improve Earth-based low-dose modeling and safety standards, the researchers engaged in which would benefit immeasurably from having a completely new population group to study who are intentionally exposing themselves to low-dose, high-intensity radiation.  This is also, *hint hint*, a completely untapped research funding angle (contact me if interested in collaborating – seriously!).

So, there you have it.  If not taking advantage of my own firm’s radiation dosimetry services, my message to the suborbital spaceflight world was to at least engage in planning one’s own flight experience armed to understand that accurate dosimetry in the space environment is not something one can just pull off a shelf and slap on the outside of a pressure suit!

Space Training Roadmap

The second talk, which was expertly given by co-conspirator Dr. Mindy Howard of Inner Space Training, involved a task-based assessment of potential spaceflight tasks for suborbital spaceflight participant.  The objective there?  The development of a spaceflight training “roadmap” to help participants decide which training amongst the many types offered by providers is relevant and necessary for their personal flight goals.

The power to decide which training is or is not relevant to an individual should not, in my opinion, be left up to the spacecraft providers (who may and likely will not have your specific goals in mind)!  That’s where our roadmap research comes in.

Please feel free to contact me or Dr. Howard for any additional details along those lines.

Lingering Thoughts

Well, the pulse at the conference was that the next twelve months appear to be crucial.  With business plans starting to kick in and metal finally being flight tested, I feel as though there are two distinct options for NSRC 2014: It will either be aflood with the excitement borne of the dawn of commercial suborbital spaceflight, or attendance will plummet as cynicism and a fear of perpetual development cycles sets in.

For now, the future looks bright, and that’s good news!

Until next time, NSRC.  Cheers!

IMG_4534

Having an equally unashamedly-good time having the opportunity to give a NSRC presentation about a topic that’s actually in my field of expertise! (I’ve been fielding for other sides of the house the past couple of years…)





The Antimatter Plot Thickens…

30 04 2013

I realize it’s been egregiously silent here at the Astrowright blog for some time.  Apparently, I am not immune to the same disappointing (as a reader) dry spells experienced in/by so many other blogs I’ve followed during the years. 

(With grad school, teaching at CSN, my day-job working for DOE, a side-business or two in flux, moonlighting the occasional and surreal TV project, and with a 1&1/2-year-old at home – let’s just say I’ve come to terms with the reality that I’m not a juggling Jedi yet.)

Excuses aside, however, I wanted to take a moment to relay a devastatingly exciting potential discovery, which itself was prompted by a pleasant surprise…

CERN's ALPHA experiment.  (Credit: CERN)

CERN’s ALPHA experiment – our Anti-Virgil into Dante’s Antimatter Inferno? (Credit: CERN)

Antimatter in Focus

AntimatterSymbolOnlyAs reported on SpaceRef.com and NASAWatch.com, which prominently featured the antimatter symbol I created a couple of years back (i.e., the pleasant surprise – thanks, Keith!), we may be one giant leap closer to figuring out antimatter – and with it, peer a little farther into the mysterious underpinnings of the Fundamental Forces of Nature.

In an article titled, “Does Antimatter Fall Up or Down?” Keith Cowing reports that researchers at CERN’s Alpha Experiment recently published in Nature Communications their tantalizing antimatter research progress.  

Specifically, these CERN specialists have identified a process for finally determining whether or not gravity acts upon antimatter the same way it does upon “ordinary” matter, even if they haven’t answered the question quite yet.  (See Keith’s article for more details on their experiment, what it means, and where it’s going.)

Down the Anti-Rabbit Hole

So, why do we or should we care about figuring out what antimatter really is and how the universe treats it?  Well, quite simply, it has the possibility of providing new solutions to many current problems in physics. 

Dark EnergyDark Matter, and questions about early Cosmic Inflation all essentially deal with versions of the same issue: There are apparent problems with the amount of force we see in the universe versus how much we should expect. 

Perhaps a shift in our understanding of fundamental forces, like gravity, will shed new light.

This is to say nothing of the mystery concerning why the universe appears to be all matter and generally no antimatter.  According to physics as we understand it, there’s no reason for the bias.  (Why not areas of high concentrations of antimatter and others of normal matter?)

Why did matter win?

And to make matters yet more interesting, the late, great Dr. Richard Feynman (and others) have described antimatter as being inditinguishable from (or perhaps actually being!) ordinary matter moving backwards through time.  While few physicists believe this is actually the case, it certainly bends neurons considering that it remains a physical possibility*.

(*I should note that this idea of antiparticles moving “backwards” in time, in order to be true, requires a reconstruction of what we mean by “time.”  This is because antiparticles don’t blip out of existence as they move to the “past” with respect to us as we, presumably, continue to move into the “future.”  Instead, we remain with the antiparticles in the same measurable “now” in the universe…)

Antimatter – A Guiding Star

Keep an eye on this one, folks.  It could very well be that the study of antimatter provides us the wedge we need to evolve beyond peering through the keyhole at the universe and instead throw open the door.

Optimistic?  Admittedly. 

However, we’re due for our big 21st Century paradigm shift in the sciences.  What with the recent 100 Year Starship Symposium hinting at what the future has to offer us (along with humanity’s expanding view of our galactic neighborhood and our desire to get out there and engage it), it’s high time we get on inventing that superluminal propulsion system to Alpha Centauri, already.

I’m not getting any younger.





Surviving Radiation in Space

13 02 2013

Apollo 10 image of Earth taken from 100,000 miles.  [Credit: NASA]

Apollo 10 image of Earth taken from 100,000 miles away.
[Credit: NASA]

For those who are interested in the reality of radiation exposure on Earth, in space, on the Moon, and what this exposure means for our prospects of manned exploration of the Solar System, read on!

The Myths and Truths of Death by Space Radiation

There are persistent groves of misinformation taking root about the lethality of radiation doses for astronauts, particularly for those who are bound for the Moon and/or Near-Earth-Objects, (such as asteroids for research or mining).

Unfortunately, these claims have been given the capacity for widespread proliferation in the fertile cyber-soil of the Internet, and worse, they usually sprout symbiotically with claims that the Moon landings were hoaxed, e.g.:

“We could never have landed on the Moon because the astronauts could never have survived the radiation from cosmic sources/the Van Allen Belts/solar wind.  Therefore, at a sound stage in the Nevada desert…”

Well, since most of these authors capitalize on the preexisting, prevalent fear of radiation to sugar-coat their misinformation pill, most people are unprepared to distinguish technically-compelling pseudoscientific fluff from interpretations of actual data.   So, the below is an effort to arm you, fellow readers, with a guide to help navigate these murky radiation/Moon hoax waters.

NOTE: NASA has produced a factsheet on space radiation as well, which covers the basics of radiation and its effects and measurement.

By reviewing some of this information, you’ll ideally emerge with an enhanced ability to see for yourselves if these radiation-lethality claims hold water.

(SPOILER ALERT: They don’t.)

So, to begin, let’s review what we know about radiation exposure right here on planet Earth.

Current Regulation Levels and Common Radiation Doses

After nearly a half-century of dedicated research, it has been found that there is no detectable increase in the incidence of cancer (the primary threat of penetrating gamma-ray radiation exposure) for people who receive an annual radiation dose of 5,000 millirem (5 rem) or less.

Consequently, the U.S. Nuclear Regulatory Commission’s (NRC) federal regulations currently limit nuclear workers to an annual dose of that amount.  Further, the U.S. Department of Energy’s (DOE) federal regulations, to be on the safe side, currently limit radiological workers’ annual doses to one tenth of the NRC’s limit (500 millirem) unless there is some sort of extreme circumstance or emergency.

But what do these numbers mean?  To help visualize this data, please see the below graph, which places these numbers in simple context with radiation doses we receive naturally from things we all can more easily comprehend, like a chest x-ray:

Current radiation exposure limits and common doses.  [Chart credit: Ben W. McGee]

Current radiation exposure limits and common doses. [Chart credit: Ben W. McGee]

As you can see, there is a certain amount of radiation exposure that we all receive just from standing on planet Earth (see the far right-hand side of the graph).  This natural radiation is unavoidable – cosmic rays can penetrate just about any shield that is not located deep within the Earth, which is itself radioactive and contributing gamma rays from below.  In fact, you will note that the DOE administrative limit mentioned above is actually less than the amount of radiation we all already receive from Earth, plants*, rocks, air, and even ourselves* in a given year.  (*Roughly 1-2% of all potassium on earth is the radioactive isotope, K-40.)

The take-home here is that none of the numbers in the above graph indicate any sort of imminent danger.  In fact, all doses depicted above are evidenced to be “safe” levels, in that they are either natural or below any exposure that the data indicates increases the incidence of cancer in a population (see: ICRP, NCRP).

NOTE:  There are actually two separate dangers that get confused during conversations about the health effects of radiation.  The first kind of danger is for lower-level exposures, which is the danger of increasing your risk of developing cancer later in life.  -This is exactly like the common knowledge that more time spent sunning or tanning during youth equates to an increased risk of skin cancer later on in life.  (It won’t harm you now, but it could harm you later.  It’s a roll of the dice based on your own health, habits, luck, and genetics.) 

The second kind of danger is immediate – the damage and destruction of cells due to a brief, intense exposure to radiation.  Following the sun-tanning analogy, this is akin to a sunburn but spread throughout your body – damage directly caused by the radiation due to its intensity.  While this may also increase your risk of cancer, the threat here is direct injury and your body’s ability to cope.

How do these natural and regulated levels of radiation exposure compare to the radiation dose levels we really know to be definitely unsafe?  For that, see the following expanded graph, which has been color-coded to relate it to the previous one:

Dangerous radiation levels in context.  [Chart credit: Ben W. McGee]

Dangerous radiation levels in context. [Chart credit: Ben W. McGee]

So, as you can see, this graph allows you to immediately identify relationships between ordinary and dangerous radiation exposures to help you understand the concept of radiation exposure and recognize how intense radiation has to be in order to be considered truly dangerous.

  • For instance, you have to be exposed to an intensity of radiation ten million times that of Earth’s normal background levels before worrying about developing radiation sickness.  That’s ten thousand times more powerful than a chest x-ray.
  • You would also need to receive 1,000 chest x-ray scans before worrying about definitely having increased your risk of developing cancer later in life by a single percentage point.

Now, with a little context, we can start to evaluate how bad the space radiation environment really is.

Explorer-1, that discovered the Van Allen Radiation Belts in 1958.  [Credit: NASA/MSFC]

Explorer-1, launched in 1958. [Credit: NASA/MSFC]

Debunking Lethal Radiation from the Van Allen Belts

The United States’ first spacecraft, Explorer-1, detected the presence of so-called “belts” of radiation around the Earth.  These were named after the scientist who designed the instrument that discovered them, Dr. James Van Allen of the University of Iowa.  However, we have learned much since then, including measurements from the radiation instrument RADOM aboard the much more recent Chandrayaan-1 spacecraft (launched in 2008).

Results from RADOM showed that the inner Van Allen belt, which extends from roughly 1,000 miles above the Earth to a little more than 6,000 miles up, appears to be composed of highly energetic particles, such as solar protons, (meaning they pack a higher radiation “kick”).  The outer belt, on the other hand, extends from a little more than 9,000 miles up to a full 33,000 miles up, and it appears to be a little gentler – it is composed primarily of electrons (beta particles).

So, just how bad was the radiation measured there?  Well, it wasn’t something to dismiss (and was academically quite interesting), but it also wasn’t something that would strike fear into the hearts of mission planners:

Peak radiation exposure while traveling through the inner, more powerful belt reached 13,000 millirem per hour, (or 13 rem per hour).  So, if an astronaut were to park in worst part of the inner Van Allen belt for an hour with no shielding, he or she would receive a radiation dose nearly three times the annual “safe” dose for DOE workers and may have bumped up their lifetime risk of a fatal cancer by a percentage point.

Fortunately, however, the time the Apollo astronauts spent traveling through the highest radiation zone of the inner Van Allen belt (at a screaming 11,000+ miles per hr) was fractional – their doses averaged 120 millirem per day.

Go ahead and compare this to the above graphs.

So, it is clear that the Apollo astronauts’ radiation doses in this case were much less than a common CT scan and far less than what a modern astronaut on the International Space Station receives during a 6-month tour (~7,000 millirem).

Hence, simply passing through the Van Allen Belts is anything but lethal.

Astronaut exposed to the raw space radiation environment on Apollo 8.  [Credit: NASA]

Astronaut exposed to the raw space radiation environment on Apollo 8. [Credit: NASA]

Debunking Lethal Radiation Doses from the Earth to the Moon

Like our own sun, all of the other stars in the night sky are nuclear reactors.  Consequently, a constant “rain” of high-energy particles and gamma rays comes at us from the rest of the galaxy, which we call Galactic Cosmic Radiation, or GCR.

Many claim that in “deep space,” e.g., the space between the Earth and the Moon or between Earth and Mars, GCR would prove lethal for a human being.  Yet, the data indicates otherwise.  (Actually, GCR is the primary source of radiation an astronaut normally experiences in all cases, whether in Earth orbit or beyond.)

Let’s have a look.

The data we have about radiation doses during travel from the Earth to the Moon, like with the Van Allen Belts, are not limited to the old Apollo mission data.  For example, the same Chandrayaan-1 spacecraft mentioned above also traveled from the Earth to the Moon and showed a dose during the five day trip (a.k.a. during “translunar injection“) of 1.2 millirem per hour.

Granted, while this is a level nearly a hundred times the average gamma-ray background radiation intensity on Earth, it is still low enough to not present an immediate concern.  Why?  See the above graphs for a comparison – An astronaut would have to spent more than 170 days in this radiation field before even reaching the NRC’s limit for nuclear workers, which equates to no statistical increase in developing cancer.

This sort of radiation exposure becomes an issue when planning long-term missions to the Moon or Mars, which involve several months to years of exposure time, but it certainly bore no immediate threat to Apollo astronauts traveling to-and-from the Moon in a matter of days.

View of the Taurus-Littrow Apollo 17 landing site, 7-19 Dec. 1972.  (Credit: NASA)

View of the Taurus-Littrow Apollo 17 landing site. [Credit: NASA]

Debunking Lethal Radiation on the Moon

Like with the trip from the Earth to the moon, radiation doses on the lunar surface did not even approach immediate danger levels, and while they fluctuated strongly with changes in the Sun’s output, the Moon itself was observed to act as a shield from galactic cosmic radiation.

Consequently, doses received by astronauts on the lunar surface were actually less than that received in lunar orbit, and again, averaged 120 millirem per day.

This value is completely consistent with measurements from the RADOM instrument in 2008 that showed radiation dose rates in lunar orbit of approximately 1-2 millirem per hour.

And again, these are far from doses that would pose an imminent threat to an astronaut’s ability to function.  An astronaut would, quite simply, need to stand in a radiation field of an intensity one hundred thousand times greater for a full hour before suffering the effects of radiation sickness.

The final space radiation threat data in context, plotted in green, can be seen in the following chart:

Space radiation doses in context.  [Chart credit: Ben W. McGee]

Space radiation doses in context. [Chart credit: Ben W. McGee]

Looking Ahead to Planetary Exploration

What does this all mean for the future of manned space exploration?  While all of this does show that claims of radiation lethality in space are plainly false, it also indicates that radiation mitigation will have to be a central planning issue in order for future astronauts to remain within the current bounds of acceptable risk.

Prevailing wisdom accepts that spaceflight and planetary exploration is inherently dangerous and limits what is considered to be acceptable risk to a 3% increase in fatal consequences as a result of radiation exposure – regulations for radiation exposure that are more lenient for astronauts than for other radiation workers.  (Surprisingly, however, this level of risk acceptance is actually more conservative than what is currently accepted for workers in other, much more prosaic terrestrial jobs in many industrial and natural resource fields… but that’s another story.)

There is some research to suggest that chronic, lower-intensity radiation exposure to some of the soft tissues of the eye may lead to secondary negative health effects, such as cataracts, but we’ve only just begun to learn what effects the many alien factors of the space environment have on human physiology, including gravity-induced modifications of bone, muscle, and organ function.  -And again, these effects are not imminently prohibitive and are certainly not immediately lethal.

The Take-Home

Radiation exposure is one of space’s primary threats – but it is not the primary threat.

A lack of atmospheric pressure, the presence of boiling and/or freezing temperature extremes, an intrinsic lack of breathable air and water, and the necessity of shielding against (or avoidance of) micrometeoroids are all arguably more pressing threats.

Radiation at any exposure rate measured in cislunar space certainly wouldn’t prevent an astronaut from visiting the moon, and only if trapped in the most unlikely and unfortunate of orbits would an astronaut ever need be concerned about the possibility of developing a radiation-induced depression of the immune system and – at the extreme – acute radiation sickness.

Take alarmists with a grain of salt and look to the data for the truth.  In fact, it can be seriously argued that conquering our fear of the atom may actually be the means by which the rest of the solar system is opened to humanity.

In my view, that’s where the real conversation is.

_____________________________________________________________

For more information on space radiation doses to astronauts, link (PDF) to the following landmark document, “Space Radiation Organ Doses for Astronauts on Past and Future Missions” by F.A. Cucinotta.








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