Summer Hits: Martian Water, Asteroid Nukes, Orbital Antimatter!

1 10 2011

Here’s a recap of some of this summer’s greatest hits in space news that you might have missed:

Water on Mars

Dark streaks as summer flow features in Newton Crater, Mars. (Credit: NASA)

In an utterly tantalizing development, scientists analyzing imagery from the Mars Reconnaissance Orbiter (MRO) have announced what appears for all the world to be direct evidence of water on Mars!

Because the MRO has been orbiting the Red Planet since 2006, it has been able to view the same portions of the world at different times of year with an eye toward spotting any potential seasonal changes.  This past August, the MRO team reviewing this growing dataset hit paydirt.

Specifically, the team identified dark streaks on the slopes of steep terrain in the southern hemisphere that are found during Martian spring and summer; these features disappear during Martian winter only to return once again the following spring.

While there are multiple possible explanations, the most likely amongst them appears to be the flow of briny (salty) groundwater that warms in the hotter months, breaches the surface, and evaporates/sublimates as it flows downhill.

Time will tell on this one, but all eyes should be on the possibility of subsurface briny Martian aquifers!

Russian “Armageddon”

Asteroid impact as depicted in the film "Deep Impact." (Credit: Paramount/Dreamworks)

This past August, Russian scientists took a note from Hollywood and seriously proposed the use of nuclear weapons as a means of asteroid mitigation.

Under the scenario, a dual-spacecraft architecture would be employed, with one spacecraft, called “Trap,” ferrying a nuclear warhead to the target while a second spacecraft, “Kaissa,” (apparently and intriguingly named after the mythical goddess of chess,) analyzes the target asteroid’s composition to determine the appropriate warhead use scenario (deflection vs. break-up).

The spacecraft would be lofted by a Soyuz-2 rocket and/or Russia’s upcoming Rus-M rocket.

While much contemporary research casts doubt on the ultimate effectiveness of a nuclear detonation in such a context, the proposers stressed that the technique would only be used on approaching objects up to 600 yards in diameter.

Orbital Antimatter Belt

Antiprotons trapped in the Earth's magnetic field (in pink). (Credit: Aaron Kaase/NASA/Goddard)

Also this past August, researchers published a stunning (but in retrospect, sensible) discovery in Astrophysical Journal Letters: Earth possess a natural orbiting belt of concentrated antiprotons.

Succinctly, the interactions of high-energy cosmic radiation with the Earth’s atmosphere can produce infinitesimal and ordinarily short-lived bursts of antimatter.  These antiparticles normally react with standard matter present around the Earth and annihilate.

However, in the near-vacuum of space beyond the bulk of the Earth’s atmosphere, some of these antimatter particles are spared immediate destruction.  Many of these antiprotons are then herded by the Earth’s magnetic field into bands or belts, which were recently discovered by the antimatter-hunting satellite PAMELA.

Aside from the “gee-whiz” factor, there are certain technical and economic reasons to get excited about the finding.  For starters, the energy density of antiprotons is on the order of a billion times greater than conventional chemical batteries.  However, at a current production cost on Earth of nearly $63 trillion per gram, antiprotons are a bit hard to come by and even less practical to use for anything other than research; Identifying a natural reservoir such as, say, a naturally-produced orbiting belt could open up additional avenues of use for antimatter as well as be immensely lucrative… if only one could solve the lightning-in-a-bottle problem of antimatter storage.

In any case, this is definitely something to keep an eye on.  For the less techno-jargon-inclined, news reports on the find may be found from the BBC as well as Science Magazine.





Radiation, Japan, and irresponsible reporting: Part III

19 04 2011

Image of one of the damaged Fukushima reactors. (Credit: Reuters)

As detailed in Part I and Part II of this series, the vocabulary of radiation science, (known as “health physics,”) is being chronically misused and confused by the news media in its coverage of the Fukushima nuclear incident in Japan, and critical context is being ignored when details are reported.  The result?  There is so much misinformation flying around that it’s basically impossible for an ordinary person to make sense of the situation.

This post series is an attempt to help.  So, to briefly recap:

  • “Radiation” cannot travel in a cloud, nor can it “settle” onto something.  Radiation is simply the atomic/sub-atomic particles and rays of x-ray-like energy beamed out from overweight, (i.e. radioactive,) elements.  The effects of these particles/rays are pretty short-range.
  • “Radioactive material” is what can do the distance traveling – actual bits or chunks of stuff – which itself emits radiation.
  • When some radioactive material lands somewhere you don’t want it, it is called “contamination,” and none of it is really mysterious.  You can wash contamination off, wipe it up, etc.  It’s really just chemistry, after all.

Let’s take a moment to further the discussion and talk about why radiation is something we don’t like, and what we can do about it.  In truth, radiation is far more natural than anyone (particularly with an anti-nuclear agenda) tends to broadcast.

Water around Idaho National Laboratory Advanted Test Reactor glows blue due to the intense radiation field. (Credit: Matt Howard)

To be completely fair, you should understand that light is radiation – that’s right, regular ol’ light from your edison bulb.  However, it’s low enough energy that it doesn’t do any damage to you.  All types of light are types of radiation, including infrared light, ultraviolet light (which is why it burns/causes cancer), microwaves (which is why it can cook your food), x-rays (which is why you need a lead apron as a shield at the hospital), as well as the stronger gamma-rays that are one of the main types of radiation people talk about when they say something is radioactive.

However, what few know is that your own body emits gamma rays.  It’s a fact (see: potassium-40).  So do plants growing in the wild, the sun above us, generally half of the mountains around you, and your granite countertops.  Our bodies are built to withstand ordinary amounts of radiation exposure.  Alpha and beta particles (other types of radiation) can’t even penetrate our skin.

Radiation is a normal part of the natural world.

Giant fireballs rise from a burning oil refinery in Ichihara, Chiba Prefecture. (Credit: Associated Press)

So, now that we understand that, of course there are intensities of radiation that are unhealthy, just as breathing too many chemical fumes can be quite harmful to you, (e.g., gasoline, cleansers under your sink, bleach, etc.)   This is one of the largest misconceptions about the Fukushima disaster – that it is the worst part of the earthquake/tsunami effects.  In my opinion it is not.

The nuclear reactors are definitely gaining the most media attention, but the biochemical aspects of the earthquake/tsunami disaster are much more widespread.  -Ruptured sewer lines across the nation.  -Burning oil refineries.  -Dumped chemical warehouses swept over by the giant wave and spread out all over the place.  -Biological hazards.  The media is ignoring the true scale of the disaster in its addiction to the nuclear mystique.

But I digress.  Yes, there certainly are harmful and dangerous levels of radiation being emitted by the damaged reactors, which like a more powerful version of a sunburn can damage DNA and cause certain types of cell mutations (cancers).  So, we ask the question: If you’re near to a source of harmful radiation, whether it’s a nuclear fuel rod or a cloud of fallout, what can you do about it?  Fortunately, the answer is very simple.  There are three things you can and should do, and these are the same things you would do in the event of a nuclear attack as well, (so take heed):

  • Get away from the source as fast as possible.  [Time]
  • Get as far away from the source as you can.  [Distance]
  • Position yourself so that dense objects are between you and the radiation source, such as hills, mountains, brick walls, mounds of dirt, etc.  [Shielding]

That’s really all you need to keep in mind, and in that order.  Time, distance, and shielding.  The intensity of radiation drops off exponentially the farther away from it you get, and the less time you spend being bombarded by radiation, the more likely your natural defense mechanisms will be capable of dealing with it and you won’t even notice.  If you can’t do the other two, then maximize your shielding and ride it out.

So, this has swelled beyond my original intent, so we’ll leave explaining the utility of iodine pills ’till next time.  But trust me.  -If you’re not in Fukushima Prefecture, you don’t need them.  (And even then, you probably still don’t.)

One final note of context.  Neither Chernobyl nor Three Mile Island (which was  nothing like Chernobyl) were a result of natural disasters.  Peculiar engineering and human error were the culprits there, respectively.

The Fukushima plant, on the other hand, took a cataclysmic magnitude 9 earthquake followed by an apocalyptic 25-foot-tall wall of water.

I think it’s a testament to their superb engineering that the reactors there are even standing at all.





Radiation, Japan, and irresponsible reporting: Part II

22 03 2011

Example of a uranium ore mine, a very natural source of radiation and radioactive material… and contamination if you track uranium dust home with you. (Uncredited)

So, after my last post, you’ve got the subtle (and not-so-subtle) differences between radioactivity (overweight atoms), radioactive material (the material containing or composed of the overweight atoms), radiation (invisible light and particles emitted by the overweight atoms), and contamination (having radioactive material someplace you don’t want it).

Hopefully, you can also see why mixing these up prevents people from making any sense of either the situation at hand or what scientists tell them (when they’re actually interviewed) on the news.

For instance, if a newscaster says something akin to, “A plume of radiation was released,” well, that doesn’t really make sense.  That’s like saying, “A plume of blue has been released.”  You can release a plume of blue something, be it smoke, confetti, etc., but you can’t release blue.

Similarly, radiation is produced by something else – so, you could say, “A plume of radioactive steam has been released,” and that means that the plume of radioactive steam would be producing radiation as it moved and dissipated, which is perfectly reasonable.  However, just saying the radiation part is nonsensical, and further, adds to the terrifying mystique around the word “radiation” …

Radioactivity is just chemistry and physics, nothing more, nothing less.

Let me provide a second example.  If a scientist reports that there is “radiation” detected somewhere, you now are prepared to understand what he’s not saying, which can actually be more valuable than what he said.  In saying that radiation has been detected, the scientist has not said that they’ve actually found the radioactive material responsible for producing the radiation, or further, any radioactive contamination.  He’s simply saying that instruments have detected either the invisible, high-energy light (gamma rays/x-rays) or atomic particles being shed by radioactive material.  The radiation in this case could be from the sun, plants, humans (yes! – we’ll get to that), granite, radon from igneous rocks, or something more sinister – the scientist hasn’t specified.  He’s reporting facts.  -At such and such a location, radiation of a given intensity has been found.

So, what can such a statement tell you?  It can tell you from a health perspective how long it’s safe to be in the area where the radiation was detected, but it says nothing about the nature, presence, or movement of the material responsible for producing the radiation.  I cannot stress how important it is that this be made clear in the media.

So, for retention’s sake, I’ll pause here to keep these posts divided into brief segments.  Stay tuned for Part 3, where we discuss how radiation is truly crippled by the laws of physics, how that can be best (and simply!) used to your advantage, and just exactly why it’s bonkers for everyone to be snapping up iodine pills.

Until then, cheers.





Radiation, Japan, and irresponsible reporting: Part I

17 03 2011

Intensity diagram of the Japan quake. The epicenter of the quake is represented by the black star. (Credit: United States Geological Survey)

While the media continues to sensationalize what is already a “gee-whiz” bewildering topic for most ordinary people on planet Earth – nuclear reactors and radioactivity – the recent run on Potassium-Iodide tablets in the United States and on the Internet betrays just how badly the outlets are throwing gasoline on the raging inferno of ignorance out there when it comes to radiation.

I can only presume this is to attract viewers.

Consider this  the first in a small series of posts that seek to contribute a clarifying voice out into the chaos.  To what end?  Hopefully, by the end of these posts, intrepid reader, you’ll understand why the nuclear reactor disasters are serious, but you’ll also see why they pale in comparison to the biochemical environmental apocalypse taking place in Japan due to everything else the earthquake and tsunami destroyed.

So, first, let’s start at the beginning.   What is radiation?

Let me emphasize – there is nothing magical or supernatural about what we call “radiation” and/or “radioactivity.”  A radioactive atom is an overweight version of a “normal” atom, and it naturally tries to get rid of energy to slim down to normal size.  To do this, it “radiates” energy in the form of intense invisible light (gamma rays) and physical bits of itself (atomic particles) away from itself.  That’s it.

Really, radiation science is a form of chemistry.  It’s equally amazing that chemicals can combust to drive cars, that acids burn, etc.  So, let’s get over the “mysterious” hump right here: Radiation is just the chemistry and phsyics of overweight atoms, and it obeys the same laws of physics as everything else.

Second, and most importantly before we go any farther, is to start to understand the terminology used (and misused) everywhere.  So, there is really only one thing you need to understand to understand how radiation works and how to deal with it, and it is this: There is a difference between “radiation” and “contamination.”  A huge difference.  -And to confuse the two is to commit a gargantuan error.

Radiation refers to the invisible light and particles that the overweight (i.e., radioactive) atoms are sluffing off.  Experiencing radiation is like basking in the glow of a heat lamp.  You can get burned/damaged by it, but it won’t come off on you.

Radioactive Material is (unsurprisingly and simply) the name given to material that emits radiation.

Contamination, on the other hand, is when radioactive material is actually moved, blown, spilled, etc., someplace that you don’t want it.  If you get covered with dust that is radioactive material (see above), then you have been contaminated.  This is what you need to wash off, make sure you don’t inhale, etc.

So, what’s the take-home?

  • You can stand next to radiation without fear of getting contaminated.  There’s nothing mysterious in the air – it’s no different than how you can walk away from an x-ray machine without fear of tracking some of the x-rays home with you.
  • Radioactive material emits radiation, but it won’t result in contamination if the material is tidy, safely contained, and solid.

You can see now how if you say, “There’s radioactive material over there!” it means something very different than, “There’s radiation over there!” and very different still than, “There’s radioactive contamination over there!”

The first sentence could simply refer to completely safe-to-handle medical sources or other, completely expected sources of radiation.

The second sentence is very ambiguous and refers to the presence of the invisible light (gamma/x-rays) or particles, meaning that radioactive material must be nearby – but it may still be completely expected.

The third sentence is the only one of the three that implies anything is wrong.  Contamination means radioactive material has been deposited somewhere you don’t want it.  So – by mixing these up, which often happens in the news, the conversation can’t even sensibly go any farther.

To be continued…








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