Remote areas of Alaska are off the wider electrical grid and are far from natural gas pipelines or railways to deliver coal.   Heat may be provided, at least in part, by wood burning stoves that can use local fuel, although wood supplies may also be limited.   However, by far the most important source of energy is oil.   Diesel oil is the only way for these communities to generate electricity and provides most of the heat.   Petroleum also powers local transportation and powers the vital systems of the communities, either directly or by generating electricity.   Communications, drinking water wells, sanitary systems, heat and lighting all require energy provided by oil.

These communities use a lot of oil, and although they may have large storage tanks, the energy density of petroleum means that they can’t go very long without replenishment.   Getting the supplies to these communities is never a sure thing.   When it does arrive it’s expensive and it’s rapidly becoming more expensive as petroleum prices go up.  Due to both the costs of oil as a commodity and the difficulty in delivering it, the final cost can be upwards of ten US dollars a gallon when it is delivered.

Via NPR:

Ultra-Harsh Alaska Winter Prompts Fuel Shortages

ANCHORAGE, Alaska (AP) — Living in Alaska’s outer reaches is challenging enough, given the isolation and weather extremes, but at least three remote communities also have experienced weather-related late deliveries of fuel so crucial to their survival during an especially bitter winter.

The iced-in town of Nome and the northwest Inupiat Eskimo villages of Noatak and Kobuk faced fuel shortages that illustrate the vulnerability of relying solely on deliveries by sea or air, potentially subjecting communities to the mercy of the elements. The villages, which just received their fuel, are especially vulnerable, unable to afford more additional storage tanks for gasoline and heating oil, which can run as high as $10 a gallon.

Compounding a problem with no easy answers, temperatures dipping as low as minus 60 over the past few weeks means air deliveries are delayed at the same time people are consuming more fuel more quickly. Some people in both villages also use wood-burning stoves for supplemental heat, but diesel is the critical commodity.

“It’s been pretty tough,” Noatak resident Robbie Kirk said of life in the community of 500, which finally received a fuel delivery on Tuesday, three days after the village store ran out of heating oil. “We usually have a nice reserve of fuel. Now we’re just playing catch-up.”

Nome missed its pre-winter delivery of fuel by barge when a huge storm swept western Alaska. In a high-profile journey, a Coast Guard icebreaker is cutting path in thick sea ice for a Russian tanker delivering 1.3 million gallons of fuel to the community of 3,500.

Without a fuel delivery, Nome would likely run out of certain petroleum products before the end of winter and a barge delivery becomes possible in late spring.

Until recently, the situation was much more dire for the smaller communities of Noatak and Kobuk, located farther north above the Arctic Circle, where relentless extreme cold prevented fuel deliveries by plane until this week, residents say.

Before the new supply of fuel arrived in Noatak, the village store borrowed some heating oil from the village water and sewer plant, said store manager Connie Walton. But filling the store’s two 23,000-gallon tanks has diverted any potential crisis.

“We’re good for another month and a half,” Walton said.

Residents in Kobuk also were highly relieved by an air shipment of heating oil that arrived Wednesday in the village of 150 people about 175 miles to the east. It’s been too cold for people to use their snowmobiles much, so gasoline isn’t as much of a concern, said City Clerk Sophia Ward. Running low on the diesel used to warm homes was another matter.

“I’m glad that it came in today,” Ward said Wednesday. “It’ll keep our elders warm.”

In Noatak, residents once had fuel shipped by barge on the Noatak River, but that has long been impossible since the river shifted and became shallow there.

Two years ago, residents began tapping into another source of fuel, thanks to the Red Dog zinc mine 40 miles to the northeast. The mine in 2009 began a program to sell gasoline and diesel to Noatak and another close neighbor, the village of Kivalina. The fuel is sold at cost, said mine spokesman Wayne Hall.

“This is strictly for what we can do to help out our closest community members,” he said. “Energy and heating costs are one of the biggest costs to families in this region.”

The program lets individuals buy fuel on Saturdays every three weeks at a staging area about 23 miles from the village. This winter, they can buy gas in 55-gallon drums calculated at $4.89 a gallon. Villagers also bring their own drums to fill with diesel fuel at $4.35 a gallon.

The latest Red Dog fuel day for Noatak took place on the day the village store ran out of diesel. So villagers formed a convoy of about 30 snowmobiles and freight sleds, and headed out in weather marked by temperatures of 47 below and, for the first 10 miles, dense fog, said Kirk, who regularly takes advantage of the sales.

“It basically cuts my heating fuel in half,” he said. “It’s pretty critical for me.”

The state also helps lower the soaring cost of electricity in Alaska’s rural areas, spending almost $32 million in fiscal year 2011 through its Power Cost Equalization program, which subsidizes residential electric rates and the power bills of community buildings. Power in most villages is diesel-generated.

With so many scattered settlements of a few hundred or less, the logistics of keeping them all supplied is daunting. The very fact that oil would be brought in by air should drive home just how difficult and expensive an operation this is. Even when the system works and fuel and electricity are available, it’s always extremely expensive. The cost may be offset by subsidies, but that only shifts the burden to the government and tax payers. Ultimately, there’s no getting around the fact that getting hundreds of thousands of gallons of diesel to remote settlements is a costly undertaking.

There is, however, another option, which could provide these isolated communities with highly reliable and economical electricity and heat regardless of the weather they are experiencing. In recent years, a number of small modular nuclear reactor designs have been proposed. These are sometimes described as “nuclear batteries,” although the name is deceptive. They’re not batteries in the traditional sense, but rather are encapsulated fission reactors, designed to provide power for extended periods of time with minimal maintenance and upkeep. Refueling intervals may be years or decades. The idea that the reactor is a kind of “black box” that simply sits on site and provides energy.

While none of these reactors have been built, all are entirely possible with current technology. The biggest problem is not technical or safety issues but regulatory problems. In the US, all nuclear power reactors, regardless of size, face the same regulatory framework. A ten megawatt reactor must go through the same level of licensing, site studies and inspections as a 1700 megawatt reactor. It must carry the same level of insurance and have the same safety systems and evacuation plans. These regulatory requirements alone can cost hundreds of millions of dollars.

Some examples of small modular nuclear reactors:

• The Toshiba 4S – A small nuclear reactor capable of producing ten megawatts of electricity and also capable of being used for district heating.   The 4S is intended to be built underground a 30 meter deep shaft.   The reactor is sodium-cooled, although a version with lead coolant has also been considered.  It would provide maintenance-free energy for about thirty years, after which the core would be allowed to cool for a year and then be replaced.   A pilot plant has been proposed for construction in Galena, Alaska and has generally been well received by the local population.  With a population of only 612, the 4S would provide ample power to keep Gelena warm and electrified during the worst winters.   Construction remains delayed because of regulatory issues.   If the Gelena plant ever does get built, it is hoped it would provide a prototype for more reactors of this type in the near future.
• SSTAR – The SSTAR is a lead cooled nuclear reactor which would be constructed off site and delivered as a fully self-contained unit and used until in place until the end of the units lifespan, at which point it would be replaced.   It’s currently under development by the Lawrence Livermore National Laboratory.  Initial plans were to have a prototype operating by 2015, but there have been few recent updates on the progress of the program.  The SSTAR is expected to be capable of generating ten to one hundred megawatts of electricity, depending on the size of the unit.   The unit would have a thirty year lifespan.
• Hyperon Power Systems Reactor – Hyperon is a privately held company which has been working to develop and market a small, self-contained prefabricated nuclear power reactor for several years.  The initial proposal was to use a self-regulating uranium hydrate reactor.  Hyperon had claimed that this would be rapidly deployed as the technology had already been proven in numerous TRIGA reactors.  In 2009, the company announced that they were shelving the uranium hydrate design in favor of a lead-cooled fast reactor, citing difficulties in getting approval for the uranium hydrate reactor and delays in development.  However, the company has also indicated it may continue to move forward with the earlier reactor design as well.  The company indicated that it would begin shipments in 2013, but it’s not entirely clear whether this will actually happen.  The proposed reactors, if they are ever built, are expected to produce about 25 megawatts of electricity and have a lifespan of up to a few decades.
• Adams Atomic Engine – A design pioneered by our good friend and fellow nuclear energy supporter, Rod Adams.  The Adams Atomic Engine is a gas cooled pebble-bed reactor.  It would be created as a self-contained unit and available in a number of sizes and configurations, depending on the end use.   The Adams Engine would use nitrogen as the coolant and a closed-cycle gas turbine to generate mechanical power for electrical generation or marine propulsion.   A similar reactor, the ML-1, was designed and constructed by the US Army in 1963, but the design never made it past the prototype phase.  The Adams Engine would have a number of differences from the ML-1 thus avoiding most of the problems experienced by the ML-1 prototype.

There are only a few of the types of small, self-contained reactors intended for sights like the remote villages in Alaska.  There are others.  Many are liquid metal cooled and others are gas cooled and pebble bed type reactors.  a few small self-contained light water reactors exist too, such as the mPower reactor being developed by Babcock and Wilcox.   In general, the light water variety tend to be larger and, due to the lower burn up of light water reactors, they do not have as long a core lifespan and therefore do not allow for the reactor to be left in place for many years without refueling or maintenance.  

Molten salt reactors are also an excellent choice for small reactors with limited maintenance and extended refueling lifespans.   Because molten salt reactors can achieve very high burnup, they do not need frequent refueling and do not require large on sight spent fuel storage.   The passive safety of molten salt reactors is another important advantage as well as the fact that they can operate at very high temperatures, allowing for small modular gas turbine power conversion systems.   Flibe Energy is a venture aimed at marketing such reactors.

Assuming the regulatory hurdles could be cleared, these types of reactors offer vast benefits that could liberate areas of the world from reliance on expensive oil, transported long distances and requiring continuous resupply.

Some areas with constant energy supply issues that could benefit from a nuclear reactor (to name a few):

• Amundsen–Scott South Pole Station
• McMurdo Station (had one briefly)
• Scott Base
• Palmer Station
• Bellingshausen Station
• Thule Air Force Base
• Diego Garcia
• Guam
• Ascension Island
• Saint Helena
• Guantánamo Bay
• Kwajalein Atoll
• Wake Island
• Yellowknife
• Red Dog Mine
• Nome
• Prudhoe Bay
• Eareckson Air Station
• Numerous Islands in the Caribbean

The solution to this problem has been the radioisotope thermal generator.   An RTG is a simple device, consisting of a strong particle-emitting isotope that produces heat and a thermoelectric generator which converts that heat into electricity.   The heat can also be used to keep vital components of the probe warm.  Unlike nuclear reactors, radioisotope thermal generators are extremely simple, have no minimum critical mass, produce little gamma and almost no neutron emissions, which could blind scientific instruments, and therefore require little or no shielding.  Modern RTG’s can provide hundreds of watts of reliable electrical power for years on end in a small, durable package.

The choice of isotope for space missions has always been, and continues to be plutonium-238. Plutonium-238 is a powerful alpha emitter which produces enormous amounts of heat energy.  Plutonium-238 produces only a small amount of low energy gamma emissions, making it easy to shield.  It’s easily prepared into ceramic oxide pellets that are chemically stable and have good thermal transfer.   With an 88 year half-life, plutonium-238 is short lived enough to be a good energy producer yet long lived enough to allow for missions of many decades.

All radioisotope thermal generators used for deep space missions have used plutonium-238.   RTG’s were also used to power the Apollo Lunar Surface Experiments Packages left by astronauts on the moon.    The RTG used for the Mars Science Laboratory provides 110 watts of electricity and uses about 4.5 kilograms of plutonium-238.  Larger RTG’s have been built for deep space probes, which provide up to 300 watts of power and use 7.8 kilograms of plutonium-238.  Some spacecraft have used multiple RTG’s, for example, Cassini was equipped with three RTG’s which provided a total of 900 watts of power to the spacecraft.

There are other isotopes that can also be used to provide power for RTG’s, but none are as desirable as Pu-238.   Strontium-90, a high energy beta emitter, which can be extracted from spent fuel, also produced significant amounts of heat, but would require substantially more shielding and produces less power per gram of material.  Isotopes of Curium have been studied as well, but also provide much less power and require greater shielding.  Americium-241 has also been considered, but at least four times as much material would be needed to produce the same amount of power, and greater shielding would also be required. Still, Am-241 is regarded as being the second most well suited fuel for RTG use.

Worldwide production of Am-241 is only a few kilograms per year, with US production capacity standing at only 500 to 750 milligrams annually.   Most of this material is already used to fill demand for smoke detectors and moisture gauges.  In order for the US to have a viable chance of using Am-241 as an RTG fuel, production would have to be ramped up significantly.

At one time, plutonium-238 was relatively cheap and easily available.  The United States had large stocks of the material and used it for numerous space missions.  Yet since the early 1990’s, that has not been the case.  Since then, only Russia has had the capacity to produce plutonium-238 and the price has skyrocketed.   US missions have been entirely dependent on plutonium-238 purchased from Russia at the cost of hundreds of millions of dollars.  Yet now even this limited supply is threatened, as Russia has begun to signal that it will no longer be able to provide the quantities of Pu-238 that the US (or potentially other nations) would require for continued space exploration.

Production of Plutonium-238:

The plutonium that can be extracted from light water spent fuel contains significant amounts of plutonium-238, but it’s combined with other isotopes of plutonium, making it unusable.  Separating out the plutonium-238 would require a complex plutonium enrichment system, which is far less practical than simply preparing the plutonium-238 on its own.

To produce plutonium-238, the first thing that is required is neptunium-237.  Neptunium-237 is produced as a byproduct of the reprocessing of spent fuel.   When a nucleus of uranium-235 absorbs a neutron, it will usually fission.  However, in a thermal spectrum reactor, some of the uranium-235 (about 18%) will absorb a neutron and not fission.  Instead, the uranium-235 becomes uranium-236.  Uranium-236 has a low neutron cross-section, so most of the uranium-236 generated in a reactor will just remain uranium-236, but a small amount of it does absorb a neutron and become uranium-237.  Uranium-237 has a very short half-life of only six days, decaying to neptunium-237.  Another source of neptunium-237 in spent fuel is the alpha decay or americium-241.

Spent fuel contains about .7 grams of np-237 for every one hundred kilograms of fuel.  That might not seem like much, but fuel reprocessing operations routinely go through hundreds of tons of fuel.   Because Np-237 is the only isotope of neptunium present in spent fuel in any significant quantity, it does not require any enrichment.  Instead, simply chemically separating the neptunium out yields nearly 100% neptunium-237.

After removing the neptunium-237, it is fabricated into targets which are irradiated with neutrons in a high flux reactor.   The targets are then removed and processed to separate out the plutonium-238 that is produced.  The plutonium-238 is then fabricated into RTG fuel tablets.

The end of US production:

The United States ended the practice of spent fuel reprocessing in 1977 when it was banned by the Carter Administration because of “proliferation concerns.”  Since then, the ban has been lifted, but as all reprocessing operations were shut down in the 1970’s and little support can be found for restarting the practice, the US still has no capacity to reprocess spent fuel.  After 1977, some material from plutonium production reactors continued, which yielded some neptunium-237, but that also ended in 1992, with the end of the cold war.

Today, the United States reprocesses no fuel at all and therefore cannot produce any neptunium-237.  There may still be some of the material remaining, though it’s doubtful that very much is left.   It should still be possible to obtain Np-237, purchasing it from countries with major spent fuel reprocessing programs, such as Russia, France or Japan.   However, this depends entirely on the willingness of such nations to provide it and may be expensive, since additional steps beyond normal reprocessing are required to produce the highly concentrated neptunium necessary for plutonium-238 production.

Getting enough Np-237, however, is not the biggest problem that the United States faces in producing Pu-238, however.   The US has a shortage of suitable reactors where the neptunium could be irradiated to produce the final plutonium-238 product.  Irradiating the targets requires a reactor with a very high neutron flux and the ability to receive materials for irradiation.  During the Cold War, the United States operated reactors at the Hanford and Savannah River sites primarily for the production of plutonium for nuclear weapons.  These same reactors could be used to irradiate materials for the production of medical and industrial isotopes along with materials like plutonium-238.  Therefore, up until the late 1980’s, the US had ample capacity for plutonium-238 production.   In the early 1990’s, the United States shut down all such reactors over “proliferation concerns.”   Russia, on the other hand, converted theirs to the full time production of peaceful isotopes, which is why they have been the world source for plutonium-238.

There are other reactors in the United States that could potentially produce plutonium-238, but not many of them.   The US has seen an unfortunate reduction in the number of research and irradiation reactors available.  Many, such as the Fast Flux Test Facility were shut down due to “proliferation concerns.”  Others like the High Flux Beam Reactor were closed after celebrities lobbied heavily against them.  Many simply were closed due to age and have not been replaced, given the lack of construction of new research reactors in the US in recent years.

There are only two reactors in operation that might be usable for producing plutonium-238.  One is the High Flux Isotope Reactor at the Oak Ridge National Laboratory.  However, the HFIR is already running at near full capacity for basic materials research and producing specialty isotopes.  It’s the only source of the vital isotope Cf-252 in the United States.  It also hosts a recently installed cold neutron source.   Because of this, the HFIR does not have enough available capacity to produce Pu-238.  That leaves one reactor: the Advanced Test Reactor.   The ATR is located at the Idaho National Laboratory.  It’s the only source in the US for production of cobalt-60, an isotope critical to medicine and industry.  It’s also one of only a few reactors that can be used to simulate extended fuel irradiation in a light water reactor, making it critical to fuel studies.  It’s not entirely clear to what extent producing Pu-238 at the Advanced Test Reactor might limit its capacity for other important functions.

The Advanced Test Reactor has been the focus of recent efforts to restart US Pu-238 production.   Several bills and proposals to begin production at the site have been floated, but funding has not been provided.  Most recently, a funding request for the relatively small amount of fifteen million dollars by the DOE was shot down by Congress.  No explanation was given, but it seems no US legislators are interested in restarting plutonoum-238 production, quite possibly because nobody’s spent any money lobbying for it and some have spent money lobbying against it.

Restarting production in the US may prove more difficult than simply finding a suitable reactor.   Producing the final Plutonium-238 tablets used for providing heat to RTG’s requires that the irradiated targets be dissolved, the plutionium-238 processed out and fabricated into the final RTG fuel.   The material is very hot, both in terms of radioactivity and literally.  Handling and processing it requires special facilities such as hot cells and plutonium chemical separation facilities.  The United States has limited capabilities in this area, with most of the facilities capable of fabricating special nuclear materials shut down over “proliferation concerns.”

That said, the US should have enough capacity for processing such materials to make at least a modest Pu-238 production program possible, if only funding is provided and the effort to do so is undertaken.   Ideally, enough would be made to allow for its use on spacecraft without extreme conservation measures taken, but that seems to be politically unlikely due to “proliferation concerns.”

In the end, we are left with a few options for the US space program, not all of them very appealing:

1. Restart domestic production of plutonium-238
2. Continue to rely on the limited Russian capacity to produce the material and hope they do not cut production or sales, as they seem to be indicating will happen.  Perhaps this could be avoided by paying an even more exorbitant amount to Russia for the material.  Continue with only limited deep space flights due to this limited source.
3. Hope that some other country steps up to the plate and starts making plutonium-238.  There’s a good chance that a country like China might start domestic production in the coming years, as they become more ambitious in their space program.  Whether they’ll share with the US is another issue.
4. Rely on another isotope that will result in less energy per kilogram, require greater shielding and therefore dramatically reduce spacecraft capabilities and increase launch expense.
5. Rely exclusively on solar power for space exploration.  Space exploration will therefore be limited to the inner solar system, out to about the orbit of mars and a little bit further, even out to Jupiter, although this will require very large solar arrays and will be restricted in capability due to very limited power capacities.   Beyond Jupiter, exploration by space probes will be impossible and will have to cease entirely.  And while exploration of the inner solar system will still be possible, landers that require significant amounts of continuous power will not be possible, thus making the Mars Science Laboratory the last of its kind.

Personally, I vote for choice 1.

Shooting down an ICBM has always been an extremely challenging problem.  There is very little time to react to the missile and they travel at extreme speed.   The distances involved are enormous and because an interceptor must also travel at extreme speed, it can easily shoot right past the target.  This is made even more difficult by the fact that modern missiles have penetration aids and decoys that are hard to distinguish from the actual warhead.  Some also have the ability to maneuver and change course, making it difficult to plot an interception point.  The earliest systems addressed this in a simplistic, though likely effective way:  They would try to destroy the incoming warhead with a massive nuclear explosion.  For example, the Spartan missile carried a five megaton radiation-enhanced warhead that could destroy incoming missiles at a distance of 50 kilometers.   Another missile, the Sprint, used a much smaller explosive and was intended as a last line of defense for warheads that were entering their terminal phase.

Such systems, however, quickly fell from favor for a number of reasons.   For one, the massive blasts associated with them could have some catastrophic effects on the ionosphere and satellites in the area.  While this may have been considered preferable to absorbing an attack with nuclear missiles, it was still a major concern.   The use of high power nuclear explosives was also considered politically impalpable and the prospect of hundreds of nuclear-armed interceptors alarmed the Soviet Union.   The Soviets responded by designing new warheads that were radiation hardened and could withstand blasts up to as close as a few hundred meters.   They also threatened to build up their arsenal of nuclear missiles to include a large enough number to simply overwhelm any defense system

In the end, the US and Soviets both signed treaties to limit such weapons.   The US system, known as Safeguard, was only operational for a few months before being shutdown.   A similar Soviet system was dramatically scaled back and eventually had its nuclear warheads replaced with conventional explosives.

Today there are some interceptor systems that use missiles to intercept ICBM’s, although their effectiveness is somewhat limited.   One of the most notable is the US Aegis anti ballistic missile system. It’s quite effective against single warhead missiles that lack penetration aids and advanced features, but the effectiveness against a barrage of modern ICBM’s is questionable.

A separate approach developed in the 1980’s and focused on the use of directed energy weapons, especially lasers.   These would have a number of advantages over interceptor missiles.  They would be able to engage the target almost instantly and could track a fast moving and maneuvering target in ways that a physical interceptor never could.  The Strategic Defense Initiative was a program initiated by the Regan administration in the early 1980’s.   It studied a number of methods of intercepting missiles and warheads but focused especially on the use of high power lasers.   President Regan would say that one reason for pushing the program was the realization that even a single nuclear missile, perhaps launched by error, could not be stopped and would inevitably trigger a nuclear war.   Therefore, the ability to shoot down a missile quickly and effectively would be an important capability to help preserve world peace.

Whatever the motivation, the Strategic Defense Initiative had decidedly mixed results.  Huge amounts of money were expended and great strides were made in the development of high power lasers and remote sensing systems.   High speed interceptors were developed which eventually were incorporated into THAAD and the Aegis system.   High powered chemical lasers were developed and demonstrated to be capable of blinding satellites and tracking missiles, but showed limited potential against actual missile threats.   A few tests were conducted that showed the lasers could destroy the bodies of missiles, but this was generally limited to fairly thin-walled liquid fueled missiles, which were largely obsolete by the time.

The YAL-1:

After the close of the program in the early 1990’s, some attempts were made to find applications for the technology.   One was the YAL-1.  The YAL-1 is an attempt to make one of the huge chemical lasers developed for SDI into a viable weapon.   The mission of the YAL-1 is to shoot down ballistic missiles during the boost phase. This is a very short period of time during which the missile is just leaving the launch site on course for its target. It would be the ideal time to shoot down a missile, since it would avoid contamination of friendly areas with any materials on the missile and provide the quickest response to the threat.

The YAL-1 is a heavily modified Boeing 747-400, which has been used to house the massive laser.   The system is much more complicated than just cutting off the nose of a 747 and sticking a big laser in it, of course.   It involves a very precise system of tracking lasers, steering optics, sensors and support systems as well as the laser itself.   Engaging a target involves the use of a complex array of targeting optics and tracking lasers, which follow and illuminate the target.  Once acquired and tracked, the primary laser is fired through a stabilized turret containing adaptive optics which compensate for beam distortion caused by the atmosphere.

The laser used is itself a complex piece of equipment. A chemical oxygen iodine laser, it gets its power from a chemical reaction that produces an excited laser medium. The laser is fed by a combination of chlorine, iodine, hydrogen peroxide and potassium hydroxide. These highly toxic and reactive chemicals are stored on the aircraft in corosion-resistant tanks. The byproducts of the reaction are discharged by a specialized exhaust system.

Now I have to admit, a massive flying laser is pretty damn cool and I’d love to have one to shoot at various things with, but the program has not been cheap. It was started in the mid 1990’s and didn’t actually reach the point of being able to test fire the laser in flight until earlier this year. During that time, it has cost tax payers more than 5.2 billion dollars.

Worse, it has a number of major problems that may well doom the plane from using its laser to do anything more than obliterate taxpayer money.
The Effectiveness Is, At Best, Questionable – Despite what you may see in sci-fi films, lasers are not the ultimate in destructive weaponry.   A laser of the type in the YAL-1 only heats the surface of a missile and attempts to weaken the skin to the point where the physical stresses on the missile fail.   This is much easier with older liquid fueled missiles, which often have thin aluminum tanks which could rupture relatively easily.  Solid fueled missiles are much tougher.   A design goal of the YAL-1 has been to engage solid fueled missiles at a range of 300 km, but it’s not clear if it can achieve this.Even if it does, it’s possible to make a missile resistant to laser weapons.  Ablative coatings or shields can prevent the heat from compromising the missile’s structure, and using a highly polished material around the tanks can be a very effective means of simply reflecting most of the laser beam away.  Other relatively simple counter measures could be employed by a savy enemy.  For example, they could launch a barrage of several decoy missiles, perhaps only having small first-stage engines and no warhead, simply to draw fire from the YAL-1 and depleted the limited reserves of laser chemicals stored on-board.

It Has Limited Range – 300 kilometers is not a huge distance, assuming it can even work at that distance.   In order to be effective, the YAL-1 would have to be orbiting in the area in the immediate vicinity of the launcher.  Even in the best circumstances, it will need to be a few hundred kilometers from the missile launch.   If it were to defend against missiles from Iran, for example, it would have to fly within Iran’s airspace.That pretty much means that the airspace around the launcher would have to already be under the control of the US Air Force and that overflying the area was already permitted.  If that is the case, then why even bother with the YAL-1?   The easier and preferred method of preventing missile launches is to destroy the launchers on the ground before they get a chance to fire.  While they can sometimes be camouflaged, a system of good reconciles and rapid strike aircraft can be very effective in making sure none ever get the chance to launch.

We Only Have One and That’s Not Enough -If you want to be able to effectively suppress missiles being fired from an area, then you will need to blanket that area on a consistent basis.  In other words, you need at least one and ideally several YAL-1 aircraft constantly orbiting.   If you ever give the enemy a chance to launch while the aircraft is not patrolling, that is when they’ll fire their missiles.   It’s rather difficult to hide the presence of something as big and unstealthy as a Boeing 747.   Like all aircraft, the YAL-1 has limited endurance.  It can remain aloft for a while using in-flight refueling, but eventually the crew will need more food, the engines will need to be inspected and the aircraft will need to land.   If it fires the laser at all, this could happen even faster.   The on-board chemical tanks only have enough material for about 20 shots at most, and it must land to have the laser system refueled.

Realistically, to have a viable force to actually suppress missiles being fired from even a small region of the world, at least ten of these aircraft would be required.  That is in addition to the other aircraft needed to keep the big 747 fueled and secure.  Each plane is estimated to cost about one hundred million US dollars to operate each year and has a capital cost of about one and a half billion dollars.   In other words, the project cost is going to be at least fifteen billion dollars and cost over a billion dollars annually to operate.

To add to the problem, the facilities, chemicals and equipment needed to service the YAL-1 is unique to only this aircraft and would not be available at most air bases.  It would either have to be brought to the area of operation or the aircraft would have to fly all the way back to the United States every time it needed to be reloaded with chemicals or serviced.

It Has Limited Capabilities Beyond Shooting Down Ballistic Missiles – If you are going to spend such an enormous amount of money on a weapons system, it would seem logical to want to be able to use it in more than the most narrow of circumstances.  Most ballistic missile interceptors are designed to also have the capability to engage aircraft or even satellites.   Few aircraft in the US Air Force inventory are good for only one very narrow and relatively rare mission.   Unfortunately, that would seem to be the case with the YAL-1.  It could, at least in principle, be used against enemy fighter or bomber aircraft, although the effectiveness is unknown and the range would be considerably less than many existing and highly effective surface to air or air to air missiles.

It’s  not considered to be a very good platform for attacking ground targets.   The thicker atmosphere at low altitudes tends to absorb the infrared laser light, severely limiting range and effectiveness.The laser could be modified to engage ground targets, but range would be reduced because more energy is absorbed by the atmosphere at lower altitudes.   And while some targets would be susceptible, hardened structures like bunkers or concert structures would be all but impervious to a laser weapon.   It  would also be many times more expensive than attacks using more conventional methods like guided bombs.  Since the YAL-1 was not intended to engage ground targets, there would need to be some modification to the tracking systems of the aircraft.

The Technology May Already Be On the Verge Of Obsolescence – Chemical lasers like the one used by the YAL-1 remain of interest for military purposes because they can generate a huge amount of laser energy from reserves of chemicals, without the need for large amounts of electrical power.   However, in recent years, advancements in battery technology and solid state lasers have started to challenge the capabilities of chemical laser systems.  Chemical lasers are limited to the number of firings by the chemical reserves on hand.  Refueling of the laser can be complex due to the precautions needed when handling the highly reactive chemicals involved.  They also require complex systems for chemical storage and delivery.

The availability of low cost, light weight lithium ion batteries and highly efficient solid state lasers is beginning to make it possible to achieve sufficient power from lasers that avoid the problems inherent to chemical lasers.  Already smaller solid state laser systems are appearing on the battlefield.  These systems are powered by generators with battery banks used to provide the brief pulses of extremely high power needed for the lasers.    For the time being, chemical lasers still seem to have the edge for super high power applications like the YAL-1, but solid state laser systems are progressing rapidly and may become the choice for applications of this power level in the near future.  In such an application, an APU and battery bank would take the place of the huge and hazardous chemical tanks.

Now, the big question:  What do we do with this thing?

Developing and building the YAL-1 has taken a huge amount of national treasure.   It is undoubtedly one of the most unique aircraft in the world, with capabilities no other has and technology that represents the cutting edge of laser weaponry.  Considering how much has been put into this thing, there must be something useful that can be done with it.

It could certainly be used for some research applications.  Testing a laser of this wavelength at various altitudes and conditions, determining the ability of various weapons to survive attack by a high energy laser is another application.  It might even be useful for certain atmospheric and meteorological research or in using lasers as part of a space propulsion system.  However, most of these could be done much more easily and at a lower cost in the laboratory or on the ground.  The amount of money spent would hardly be worth it if the YAL-1 only sees use as a very limited application scientific experiment platform.

As a weapon or defensive system, the YAL-1, realistic uses are harder to think of.   A fleet of ten of these is just not going to happen given the cost.  It’s possible one or two more might be built, if a viable use could be found for such a small fleet.

About the best I can think of would be to retain the anti-ballistic capability, but with the understanding that it will be pretty limited in coverage and to make the modifications necessary for engage targets on the ground.  For ground targeting, the YAL-1 could be useful for destroying targets where extreme levels of precision are required, far beyond what could be achieved with even the best guided bombs and missiles.  This might work for targeted assassinations of enemy leaders or if a vital target like a communications exchange is located right near a hospital or school.

But damn, that’s a lot of money for a weapon with no real deterrent value and little chance we’ll ever use.

Via HealthCanal:

New Take on Impacts of Low Dose Radiation
Berkeley Lab Researchers Find Evidence Suggesting Risk May Not Be Proportional to Dose at Low Dose Levels

Researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab), through a combination of time-lapse live imaging and mathematical modeling of a special line of human breast cells, have found evidence to suggest that for low dose levels of ionizing radiation, cancer risks may not be directly proportional to dose. This contradicts the standard model for predicting biological damage from ionizing radiation – the linear-no-threshold hypothesis or LNT – which holds that risk is directly proportional to dose at all levels of irradiation.

Imaging of a cell’s DNA damage response to radiation shows that 1.5 minutes after irradiation, the sizes and intensities of radiation induced foci (RIF) are small and weak, but 30 minutes later damage sites have clustered into larger and brighter RIF, probably reflecting DNA repair centers.

“Our data show that at lower doses of ionizing radiation, DNA repair mechanisms work much better than at higher doses,” says Mina Bissell, a world-renowned breast cancer researcher with Berkeley Lab’s Life Sciences Division. “This non-linear DNA damage response casts doubt on the general assumption that any amount of ionizing radiation is harmful and additive.”

Bissell was part of a study led by Sylvain Costes, a biophysicist also with Berkeley Lab’s Life Sciences Division, in which DNA damage response to low dose radiation was characterized simultaneously across both time and dose levels. This was done by measuring the number of RIF, for “radiation induced foci,” which are aggregations of proteins that repair double strand breaks, meaning the DNA double helix is completely severed.

Berkeley Lab biophysicist Sylvain Costes is generating 3D time lapse of DNA repair centers in human cells to understand better how cancer may arise from DNA damage. (Photo by Roy Kaltschmidt, Berkeley Lab)

“We hypothesize that contrary to what has long been thought, double strand breaks are not static entities but will rapidly cluster into preferred regions of the nucleus we call DNA repair centers as radiation exposure increases,” says Costes. “As a result of this clustering, a single RIF may reflect a center where multiple double strand breaks are rejoined. Such multiple repair activity increases the risks of broken DNA strands being incorrectly rejoined and that can lead to cancer.”

Costes and Bissell have published the results of their study in the Proceedings of the National Academy of Sciences in a paper titled “Evidence for formation of DNA repair centers and dose-response nonlinearity in human cells.” Also co-authoring the paper were Teresa Neumaier, Joel Swenson, Christopher Pham, Aris Polyzos, Alvin Lo, PoAn Yang, Jane Dyball, Aroumougame Asaithamby, David Chen and Stefan Thalhammer.

The authors believe their study to be the first to report the clustering of DNA double strand breaks and the formation of DNA repair centers in human cells. The movement of the double strand breaks across relatively large distances of up to two microns led to more intensely active but fewer RIF. For example, 15 RIF per gray (Gy) were observed after exposure to two Gy of radiation, compared to approximately 64 RIF/Gy after exposure to 0.1Gy. One Gy equals one joule of ionizing radiation energy absorbed per kilogram of human tissue. A typical mammogram exposes a patient to about 0.01Gy.

Corresponding author Costes says the DNA repair centers may be a logical product of evolution.

“Humans evolved in an environment with very low levels of ionizing radiation, which makes it unlikely that a cell would suffer more than one double strand break at any given time,” he says. “A DNA repair center would seem to be an optimal way to deal with such sparse damage. It is like taking a broken car to a garage where all the equipment for repairs is available rather than to a random location with limited resources.”

However, when cells are exposed to ionizing radiation doses large enough to cause multiple double strand breaks at once, DNA repair centers become overwhelmed and the number of incorrect rejoinings of double strand breaks increases.

“It is the same as when dozens of broken cars are brought to the same garage at once, the quality of repair is likely to suffer,” Costes says.

You can read the rest of the article here. The level of the data available is new, but the conclusion is not. The available data that has been collected for decades on both a microscopic and macroscopic level clearly shows that radiation dose does not produce a linear level of dna damage until it reaches a relatively high exposure level.

Unfortunately, this has never seemed to unseat the suborn linear non-threshold model, which continues to be the standard for most radiation exposure policy. I also doubt that this new data will do much to change that, although when studies like this do come out, it is certainly worthwhile to try to raise as much publicity as possible for it.

From the standpoint of nuclear energy policy, this data almost seems moot. The actual radiation level that the public is exposed to from nuclear energy is so tiny that even if LNT is used as the standard for exposure limits, one comes to the inevitable conclusion that it is more important to tear down all the granite buildings than to stop using nuclear energy. Therefore, no scientific data is ever likely to unseat the radiation argument against nuclear energy, because it was never based on science to begin with.

Fission was recognized as a potential energy source after the possibility of a fission chain reaction was realized.  A chain reaction occurs when neutrons produced by nuclear fission strike other fissile nuclei, releasing more energy in a self-sustaining reaction.   In 1942, an experiment at the University of Chicago proved that nuclear fission could indeed produce such a chain reaction.   The first artificial fission reactor was created by piling large amounts of uranium together with ultra-pure graphite blocks.  The graphite slowed neutrons, making them easier to absorb by the uranium nuclei, resulting in the fission chain reaction.  In 1945, the first artificial fission chain reaction to occur without the aid of a moderator when the first nuclear weapon detonated in the Trinity test.  The Trinity device used plutonium as the fissile material, an element produced in nuclear reactors at the Hanford site.   Plutonium is too short-lived to be found in large quantities in nature.  Another bomb, fueled by uranium was the result of years of painstaking isotope separation, which increased the amount of fissile uranium-235 available to far beyond what is found in natural uranium samples.

For many years, it was believed that such fission reactions were always limited to these artificial circumstances.   Nuclear fission, it was thought, was the result of painstaking efforts by mankind to gather up the necessary materials, enrich beyond their natural concentrations and either bring them together rapidly in large quantities or place them in the special conditions inside a reactor, where neutron moderators make it possible to sustain nuclear fission.

In 1940, Russian scientists observed the phenomena of spontaneous fission, where heavy elements like uranium split on their own without the need for a neutron to cause the event.  It was also known that uranium atoms could split as the result of a neutron generated by cosmic rays.   However, such events are uncommon and produce little energy.   They are distinct from the chain reactions that had only been observed in human-created nuclear reactors.

All this changed in 1972, when an unusual discrepancy in the concentration of uranium-235 from a mine in Gabon Africa was detected.  Chemical analysis of a unique uranium deposit  indicated that the formation had sustained a fission chain reaction at one time.   The possibility of a natural nuclear reactor of this type had been suggested as early as 1956, but the Gabon discovery was the first time that such an event was confirmed to have happened.  Further investigation of the site identified at least sixteen regions of the deposit where the concentration of uranium and lighter elements clearly indicated that significant amounts of nuclear fission had occurred.

The reactor at Gabon operated about 1.7 billion years ago, producing chain reactions for at least hundreds of thousands of years.   It was remarkably similar to modern, artificial nuclear reactors.   Fission occurred when water seeped into cracks and pores in the deposits of extremely high grade uranium ore.   The water acted as a moderator, causing the chain reaction.   In modern times, water can only be used as a moderator in reactors where the uranium has been slightly enriched to contain more uranium-235 than found in nature, but because uranium-235 has a half-life of about seven hundred million years, there was a great deal more when the Gabon reactor was critical.

Exactly how long the Gabon reactor was critical or how much energy was released is not known.   Scientists have estimated that it probably generated about 100 kW of power and likely operated intermittently due to the buildup of neutron poisons and variations in the water levels in the rock.   It also generated some amount of plutonium-239 and other heavy isotopes, which would have added to the available fissile fuel.

There has been some debate about just how common reactors like that found in Gabon may have been.   While the Gabon deposit is the only one that is known to have sustained nuclear fission, that certainly does not mean it was the only one.  In fact, there were almost certainly others, possibly many others.  The geological record is incomplete for the period of time that the Gabon reactor was critical.  The vast majority of geological formations from over a billion years ago have long been obliterated by erosion, subduction, volcanic activity and other forces that continuously shape the earth’s crust.    Even if these reactors were once common on earth, we would not expect to find the evidence and the fact that at least one still exists intact at all may be sheer luck.

What is known is that deposits of uranium in concentrations high enough to potentially sustain such reactions are fairly common, even today, and while they don’t have the necessary isotopic concentrations to produce a fission chain reaction, they would have in earth’s early history.   The further back one goes, the higher the concentration of uranium-235 would be and thus the more easily a fission reactor could have come together.  Debate continues about the time scale when such reactors could have functioned, with some arguing that such naturally occurring uranium concentrations would require high levels of oxygen in order for the necessary geochemical processes to occur.

Yet the lack of a complete geological record ultimately makes it impossible to know for certain.   Reactors may have been very commonplace billions of years ago and they may have existed for some time after the period the Gabon reactor was dated to.   It’s remotely possible that a combination of plutonium produced within such reactors and the presence of better moderating materials, such as naturally-occurring beryllium allowed these formations to produce fission chain reactions even more recently than would have been possible with the Gabon reactor.

All that can be said is that there was a period of time in Earth’s distant history when natural nuclear reactors were possible and existed and they may very well have been fairly commonplace.   This itself is a huge revelation.

A reactor at the center of the earth?

Upon learning of the natural reactor discovered at Gabon, nuclear chemist J. Marvin Herndon hypothesized that nuclear fission might actually be far more central to the formation and conditions of earth than had been previously though.   Herndon suggested that if sufficient uranium existed in the core of the earth, it could result in a massive fast fission reactor, which would be capable of producing enough fuel through breeding to sustain fission for billions of years.

Herndon’s assertions have not generally been accepted by the mainstream geological community.   Direct evidence of such a reactor is relatively limited, although the levels of helium isotopes measured in volcanic samples have been intriguingly close to those that the hypothesis predicts. None the less, if true, the georeactor hypothesis would be an elegant explanation for a number of observed phenomena.   It would explain the source of apparently excessive heat in the earth’s core and mantel, which has traditionally been attributed exclusively to nuclear decay.   It also could explain the mysterious phenomena of magnetic pole reversal, which could have been caused by periods when the reactor stopped due to the buildup of neutron poisons, only to start again once they had decayed away.

There is, however, some other data which appears to dispute the possibility of a reactor at earth’s core.  It such a reactor did exist, the bulk of the earth would prevent gamma rays or neutrons from being detectable, but it should still be possible for neutrino detectors to measure the characteristic neutrinos generated from fission reactions in earth’s core.   The data from such detectors does not support the hypothesis that a nuclear fission reactor provides a significant proportion of the heat in the core and mantle of the earth.   Such a reactor could still exist, but it would have to be less than about three terawatts or a greater number of neutrinos should have been detected coming from the earth’s core.  In that case, the reactor would only account for a small portion of the 40 terawatts of observed geothermal activity.

While the neutrino data may seem to indicate that a large nuclear reactor is not currently operating within the earth, it does not rule out the possibility that such a reactor has operated intermittently and that it is currently either not producing a fission chain reaction or is only producing a small one.   Even if that is the case, the residual heat of such a reactor would be very significant.   It is also possible that a redactor existed at one time, perhaps billions of years ago, but has not produced a chain reaction since.   If this is the case, the implications are still enormous for the formation of the earth and the heat and magnetic fields observed to this day.

Implications for earth and beyond:

We really do not know if there is indeed a georeactor or if there ever was.  While the hypothesis is controversial, it cannot be completely discounted and must be considered a possible factor in the structure and formation of the earth.  The implications are quite profound and could rewrite our most basic presumptions of the planets history and formation.

What we can say for sure is that nuclear fission reactors did exist on earth, at least in the crust.  The influence of such reactors must now be considered as an influence on everything from the mineralogy of the earth’s crust to the formation of early life.   The amount of uranium and its daughter products observed in the modern earth may be less than what once existed due to much of the element fissioning away.   Some of the lighter elements that are abundant in the crust may be the byproducts of this fission.  The heat generated by these reactors could have played a major role in shaping the early geology of earth.  It may have even influenced life, possibly heating bodies of water or producing hot springs, where heat-dependent microbes flourished.   It’s even possible that the ionizing radiation generated by the reactors was a factor in the early formation and evolution of organisms.

But even if fission chain reactions did not play a major role in the history of earth, it does not diminish the potential importance on a cosmic scale.   If fission occurred naturally on earth, then we can be certain that occurred naturally elsewhere and continues to occur naturally elsewhere in the universe.   Similar reactors could have existed on other terrestrial planets in our solar system or may have contributed significant amounts of energy to the primordial planets as they formed around the sun.   It has been suggested that fission reactions could also account for the energy observed from the gas giant planets of the solar system.

With more than a billion billion stars in this galaxy alone, there are certainly other places where fission occurs and where it could easily play an important role in how planets form or how life might develop.  As a source of energy, fission could potentially provide the heat necessary for life to exist on planets or planetoids too far from stars to otherwise support life.   It could even mean that otherwise frozen bodies in interstellar space could harbor life.   This alone could vastly change our current ideas of where life might exist beyond earth.

The suggestion that fission could also play a role in the ignition of stars is yet another intriguing, if unorthodox hypothesis that needs to be at least considered.

Whatever role fission plays in the energy balance of the earth and the universe, we now know that it does play some role.  It happens.   It’s a fundamental reaction and a source of energy in nature.  It must be considered in cosmic and geological models as a potential influence.  Uranium and other heavy elements are formed in supernova and are found across the universe.   The distribution of these elements now needs to also be considered as an important factor in which kinds of reactions can occur in which areas.

The more practical side:

The artificial nature of fission has always been used as an argument against it.   It has been claimed that it produces materials that are not normally encountered and have properties that are different from any pre-existing substance and that the uniqueness of the reaction and its byproducts makes it unpredictable.   It has also been argued that since the sun and other stars are powered by fusion, nuclear fusion is therefore a more perfect, cleaner energy source that we have always lived with, while fission does not have the same kind of appeal.

We now know that this is simply not true.   Fission can and does happen on its own, without human intervention and has so for billions of years.   Fission chain reactions and the byproducts of fission are not alien to earth and their existence did not halt life, but may have facilitated it.  They can exist in the environment without causing catastrophe and always have.   Fission is not unusual and is certainly not a creation of man.   It is a basic reaction, as fundamental as fusion or fire.

We live in a nuclear powered universe.  The energy we experience may have come from nuclear fusion, fission, decay, from the reactions of cosmic rays or even from the subatomic reactions that occurred moments after the big bang.   Nuclear reactions generate all energy, liberating it from the forces that bind all mater together.  These reactions will happen with or without our intervention.

We would be fools to not realize this and use nuclear energy to our own advantage.

This is truly one of the most exciting unmanned space missions in a long time, and perhaps the most exciting to visit mars since exploration of the planet’s surface began in 1978 with Viking 1.   The probe is a rover, somewhat similar in design to the rovers Spirit and Opportunity which proved to be astoundingly long-lived and robust machines.

It’s build on the success of the previous rover missions, but is far more bold and ambitious.  The rover will be physically much larger than the previous rovers and will have considerably greater scientific instrumentation and on board computing power.   The rover will carry extensive analytical instruments.  Like previous rovers it will have an alpha-particle x-ray spectrometer, but will also have a laser-induced breakdown spectroscopy system, along with a host of other scientific instruments for analyzing soil and rock, examining samples and detecting environmental variables like particle radiation, temperature, pressure and light levels.   The rover will have the best camera systems yet taken to mars and will be able to take full motion video, even capturing ten frames per second of high definition video.   With two gigabytes of radiation-hardened storage it will be able to cache thousands of pictures and volumes of scientific data for transmission back to earth.

What makes this all possible and what makes the MSL so much more capable than previous rovers is the source of power.   Spirit and Opportunity were designed to be solar powered.  As we all know, solar cells don’t provide a huge amount of energy on earth, but on mars it’s even less.  Under ideal conditions, the Exploration Rovers could gather .6 kilowatt hours of energy each day from their solar panels.   However, conditions were rarely so good and dust on the panels made the amount of energy the panels provided in a day even less.  This is a severely limiting factor, forcing the rovers to spend considerably more time sitting idle and charging their batteries and making it a necessity that energy be used as frugally as possible.

The Mars Science Laboratory has its own nuclear power source, providing vastly more power, day or night.   It’s not a reactor but a radio thermal generator, powered by the decay of plutonium-238.  The power source will deliver a constant supply of more than 100 watts to the spacecraft.  By mars probe standards, that’s a real lot, especially because it’s continuous.  With a half life of 88 years, it’s likely that the mission will end due to equipment failure before any noticeable reduction in power output occurs as a result of the decay of the plutonium-238 heat source.

Getting enough plutonium-238 to power future missions could be a problem due to lack of capacity to produce it in the US and tightening supplies from Russian producers, but that’s another story.

Despite the astounding science that is provided by interplanetary missions, the use of anything “nuclear” for any purpose is sure to draw some protests.   (Don’t even get me started on how stupid it is to complain about polluting outer space with radiation)  Some of the opponents claim that the material is so dangerous it could cause catastrophe if the rocket exploded or the probe crashed back to earth.  Of course, both because of the design of the RTG and the material used, dispersal is unlikely even in that event, and the worst case would result in only minimal exposure to anyone.  Still, some have tried to stop the launch or at least protest it.

But not many seem to really be buying into it anymore.  In fact, the protests have dwindled down to almost nothing…

Via Florida Today:

Plutonium protests can’t draw a crowd
Don’t expect protesters to turn out in force over the potential safety risks from Saturday’s planned launch of the plutonium-powered Mars rover Curiosity from Cape Canaveral Air Force Station.

Citing everything from apathy to holiday and shopping distractions, those known for staging protests during past launches of plutonium-fueled probes from the Cape and Kennedy Space Center will be no-shows this time around.

An Atlas V rocket carrying the rover and its 10.6 pounds of plutonium-238 is scheduled to launch at 10:02 a.m. Saturday.

“It’s not that we’re not concerned, but folks are so worried about the economy right now it’s hard to drum up support over something that ‘might’ happen,” said Maria Telesca-Whipple, a Rockledge resident who is an organizer with the Global Network Against Weapons & Nuclear Power in Space.

…

Past NASA launches of plutonium-fueled probes, such as New Horizons in 2006, Cassini in 1997, Ulysses in 1990 and Galileo in 1989, have drawn protesters to the Space Coast. All launched without any release of radiation.

But efforts to rally protesters to show up for Saturday’s launch have proved futile, organizers said.

Pax Christi Tampa scheduled a rally two weeks ago at a busy intersection, and “no one showed up,” said John Stewart, who spearheaded the event and has been pushing an opposition movement in Florida since the summer. He’s sent out more than 400 newsletters, handed out flyers on the street and been on radio to warn Floridians. But, thus far, he admits he’s received no feedback.

“Global Network Against Weapons & Nuclear Power in Space.” Wow. I guess they spend most of their time protesting the sun. Dare I suggest that maybe it’s not simply other concerns distracting the public,m but maybe people are actually wising up? Or perhaps the public is impressed by the images and information brought back by space probes and is realizing that these are great achievements of science that should be supported. (I can dream, right?)

I am a little concerned, however.   Excited as this mission makes me, it also leaves me a little worried.   The probe has a long and treacherous trip to mars and must survive a very rough landing.  Despite all the engineering that has gone into it, probes have failed many times and this mission is certainly not a sure thing.   It’s a lot of money and a huge capability being placed on one probe, so I’m sure I’m not the only one holding my breath for it to succeed.   Hopefully this August I’ll be letting out a huge sigh of relief and seeing some amazing pictures get beamed back.

The AC Gilbert set was certainly the most elaborate and complete atomic energy set sold, but it was not the only one. The American Basic Science Club produced a similar lab set around 1960, and Chemcraft produced a lab set in the late 1940’s to early 1950’s. In the 1950’s, some Chemcraft chemistry sets also included radioactive materials and experiments that could be done with radiation.

I have always thought that these sets were an incredibly good idea and a really excellent way to acquaint young people with the basics of radioactivity and, importantly, demonstrate that radiation is common and not something to be feared. These lab sets were extremely safe. The amount of radioactive materials present in the experimental sources was microscopic and not at all dangerous. The uranium ore or uranium compounds included are not a radiological hazard and are only a toxicity hazard if they are ground up and snorted or otherwise inhaled, and even then, are less toxic than an equivalent quantity of something like lead.

There’s really no better way to get a kid acquainted with science than to actually do some hands-on activities. They improve understanding and retention and allow them to participate directly in making exciting observations. Anyone lucky enough to have had one of these labs as a child probably grew up with a healthy understanding (and not fear) of radioactivity.

Sadly, the world has changed since the early 1950’s, and today most people seem to run around with rampant radiophobia. If something is “radioactive” (which nearly everything is) then it’s seen as being of the highest danger. Nothing is believed to be more environmentally destructive, more dangerous to health, more disastrous, more hazardous and more terrifying than radiation. The idea that at one time children were allowed to learn with materials that produce radiation significantly above background levels fills some with horror and others laugh at just how stupid everyone must have been fifty years ago.

Here’s some of the things that have been said about the AC Gilbert Atomic Lab:

From the Daily Grind:

World’s Most Dangerous Toys: Gilbert U-238 Atomic Energy Lab
If you thought choking hazards in toys were bad then spare a thought for American kids in the early 50′s.

Introducing the Gilbert U-238 Atomic Energy Laboratory. This toy lab set was produced by Alfred Carlton Gilbert between 1950 and 1951 and sold for $49.50US (which is equivalent to about $380 – $400US dollars today). So if you were lucky enough to have well off parents back in the day you may well have been ‘lucky’ enough to get your hands on this radioactive fun set.

From Liveleak:

Very bad toys: Atomic Energy Lab usa ca. 1960
t’s unclear what effects the Uranium-bearing ores might have had on those few lucky children who received the set, but exposure to the same isotope
U-238 has been linked to Gulf War syndrome, cancer, leukemia, and lymphoma, among other serious ailments. Even more uncertain is the longterm impact of being raised by the kind of nerds who would give their kid an Atomic Energy Lab.

From Cracked

The 8 Most Wildly Irresponsible Vintage Toys
#1. Atomic Energy Lab

As a kid, did you ever swallow or at least put in your mouth a small piece of a toy or play set? Did you grow an extra arm because of it? No? Then you probably didn’t have the Atomic Energy Lab.

You see, there was a different approach to nuclear power in the ’50s and early ’60s — atomic energy was our friend and the way of the future, and it would never do anything to hurt us. However, it’s still hard to believe that anyone would entrust kids with radioactive material (even in small doses).

Yet, the Atomic Energy Lab kit produced by the American Basic Science Club came with real samples of uranium (which is radioactive) and radium (which is a million times more radioactive than uranium). Since the mere presence of radioactive material in a children’s product clearly wasn’t insane enough, some of the experiments detailed in the manual also required kids to handle blocks of dry ice. Dry ice, by the way, has a temperature of minus 109.3 degrees Fahrenheit, and it’s recommended that it only be handled while wearing gloves (none were included).

Okay, they’ve got a point about the dry ice, although it’s reasonably safe to handle with basic precautions. Still, I’m downright offended by the way that people completely ignorant of what radiation is or the dangers can sit there and smugly dismiss the idea of a radiation experiment set as being insane. It’s often ranked the most dangerous toy of all time, but in fact, it’s not dangerous at all for any normal 12 year old to learn from a microscopic amount of a radioisotope or a little bit of uranium ore, which they may well have sitting in their backyard anyway.

I’ll go one further:  Not only do I think this was a great idea and a very positive learning experience, I also think that there has never been a better time for something like a radiation and nuclear energy lab set!  Having a set that had a good variety of experiments would be fairly expensive but not unaffordable.  It would be targeted at ages 12 to adult and could also be something science departments at schools might be interested in.

I’m seriously considering doing it!  I’ll take the flack for selling kids a horrible cancer-causing evil material if I have to, because somebody has got to do it, and if I get enough interest I may very well start putting some kits together.

Things to include:

1. A Geiger counter - this is undoubtedly the most important part of the lab, but also one of the most problematic.  The cost could easily drive the price of the set way too high if a high quality Geiger counter is used. Detecting alpha particles would be great as a way of teaching of the different types of radiation but most inexpensive Geiger-Muller tubes can only detect gamma and high energy beta. Detecting alpha particles requires a very thin window, usually made of mica. That tends to drive the price up, so alpha detection may need to be omitted. Ideally the Geiger counter should connect to a computer to expand the types of experiments possible and allow data logging. This may drive the price up too high, however.
2. A set of shielding materials – One of the most fundamental lessons is understanding the nature of shielding, so a series of materials would be provided.  These would include Mylar, thin plastic, thicker plastic, metal sheets and lead foil, possibly coated in plastic to relieve fears of lead poisoning.
3. A spinthescope or scintillation screen material – This would provide one alternative for detecting alpha particles that the geiger counter can’t.  It also is a fun and interesting experiment to view the radiation-created flashes of light in a darkened room.
4. A cloud chamber - An absolute must for any basic nuclear energy lab kit.   Simple cloud chamber kits are already available
5. An electroscope – To demonstrate the ionizing effects of radiation and the earliest types of detectors
6. High power rare earth magnets - to demonstrate that particle radiation can be effected by magnetic fields.
7. A guide to identifying radioactive minerals – basically a book with types of uranium and thorium ore shown with their geographic distribution and general characteristics shown.
8. An experiment guidebook – A list of the different experiments possible

Included radioactive sources:

1. A sample or multiple samples of uranium ore
2. Uranium marbles - They’re cheap and easy enough to obtain and provide a safe base level for some experiments
3. License Exempt Sealed Sources – The company Spectrum Techniques manufactures samples of various radioactive substances, including thalium-204, strontium-90, cesium-137, lead-210 and polonium-210 that are available in either needle sources (used primarily for cloud chambers) or sealed in plastic discs.   The sources are approved for sale and possession without a license because the actual amount of material is tiny.   They run from about fifty to eighty US dollars each.  Since Po-210 has a very short halflife, including it with a cloud chamber or other product presents a problem, so Spectrum Techniques offers a coupon that can be included with such products and then mailed in to receive the sample once the consumer gets the product.

Possible Experiments:

1. Measuring radiation – Basic measurements with the Geiger counter, measuring various sources.
2. Measuring radiation in your environment – Use the Geiger counter to measure the baseline background in various areas and record how it changes by time of day.  Look for radioactive items.   What common items emit radiation and how much?    Go on a hunt in an antique store, your kitchen or somewhere else and see what you can find.
3. Prospecting - Using the Geiger counter and the guide to minerals, what types of ore can you find?
4. Shielding Experiment – Observe how various types of radiation can be shielded and attenuated.  Use the shielding to help determine the type of radiation being measured.
5. Cloud Chamber Experiments – Observe particle paths in the cloud chamber using various sources.  Also see how magnets can alter the paths of particles.
6. Spinthescope Experiments – Observe alpha radiation with the spinthescope and also use it to help determine what kind of radiation is being measured.
7. Find a hidden source – Have a friend hide one of the radioactive sources in a room and use the Geiger counter to find it.

Of course these experiments would have more descriptions and some of them might even be designed to dispel myths, for example, those who live near a nuclear power plant would be encouraged to measure radiation at various distances and plot the levels.  Also, cell phones could be on the list of items to examine to show they do not give off ionizing radiation.

Cost:

I’d like to keep the kit affordable, ideally, about 300 US dollars as the top end of what it should cost, but realistically, it may turn out to be more.  I’d consider 500 USD to be the absolute maximum that could be charged without making the set far too expensive for most people to afford.    I’m more than happy to put such a kit together at almost no profit.   To be perfectly fair, I think it’s reasonable that I would make a small amount of money (perhaps $25 or so) over the cost of the materials, because I’m going to incur other miscellaneous expenses like printer toner, paper, phone calls and my time spent putting such a kit together.   However, my primary goal is not to make money off of this so much as to produce an educational experiment kit. Most of the items included would not cost much.

The marbles, ore and shielding material could be acquired for under $50 and the cloud chamber for not much more.   United Nuclear sells a spinthariscope for $35.  It would probably be possible to get it a bit cheaper if such an item was purchased in bulk. Other expenses would include the packaging and instructions.   The cost before the sealed sources and Geiger counter is therefore going to be about $100.

The sealed sources are going to be the first big expense.   A complete set that includes a beta emitter, a gamma emitter and an alpha emitter is going to cost about $150.   I’m a little split on whether to include Po-210.  On one hand it’s the only exclusive alpha emitter that could be included, but on the other, it’s rather short lived.   The alternative would be to include lead-210 in equilibrium with polonium-210, which would produce both beta and alpha particles.   Adding another gamma emitter to demonstrate the differences in energy levels would be great too, but for a real complete set of radioisotopes, it starts to look more like $175-$200.  It’s possible it could be less if they are bought in bulk. Therefore, the kit is already reaching the $300 mark before the most important component, the Geiger counter is added.

Choosing exactly what Geiger counter to include will be a challenge.   I can definitely acquire Geiger counters that fit all the necessary criteria and are inexpensive, but generally those are units I’d get surplus or second hand, and thus are each different.   That won’t work here.  What is needed is a standard Geiger counter that will be the same for each Set.

The Russian Company Quartex makes a series of Geiger-Muller detectors that are fairly cheap and very simple to use.  Unfortunately, these units have some major drawbacks.  For one thing, they only measure gamma radiation and hard beta radiation.  That might be acceptable if not for the fact that they also only give readings in dose equivalent, not in counts per minute.  Since the point of the set is understanding how radiation is detected and measured, the more basic unit of CPM is preferable.

Still, it is a complete radiation detector in a nice, small and simple handheld unit.   It may be worth talking to the company to find out if it would be possible to make the one small modification of adding a counts per minute or counts per second reading.

Another option would be to build a GM detector-counter.  The Electronics Goldmine has a Geiger-Muller driver kit, which includes the high voltage supply and and detection circuitry for $30.  That price would be tough to beat by acquiring the components individually, and it has the big advantage of having a per-fabricated circuit board, which would be expensive to have manufactured and time consuming to fabricate individually.   The unit still needs an enclosure, battery holder and switch, but that should be obtainable for about ten US dollars.  The kit does not include a meter movement, so that will need to be added too.  An analog meter would need to have some kind of range switch (to allow for ranges such as 0-100 cpm, 0-1000 etc), which would complicate construction a bit.   There is a digital meter adapter available for about $60, which would work nicely and also adds the ability to hook the unit up to a PC.   The most expensive part of the counter will be the tube.  A suitable, although very small tube could be bought for about $60 each.   This tube would be sensitive to alpha, but given the small size, it would not work very well for general survey work.    All in all, the cost of this geiger counter, including shipping and expenses like solder and wire looks to be about $175, resulting in a total cost of the set of close to $500.

Another option would be to use the venerable CDV-700 as the basis for the detector.   The CDV-700 is a Geiger counter manufactured for the US government during the Cold War.  It was standard issue for fallout shelters. Tens of thousands were manufactured.   Production ended in the 1970’s and since then, many have been sold off as surplus.   It’s about the cheapest Geiger counter that can be purchased, often available for about $50 from a surplus dealer and sometimes less if bought in bulk.  It comes with a small check-source mounted on the side.   This is often depleted uranium but occasionally may be a sealed radium source.  It would definitely be a nice bonus to have an extra source included.

Unfortunately, the CDV-700 has a number of major drawbacks.   For one thing, it will be important to find the right version of the unit.  It was produced by a number of manufacturers and went through a few design changes over the course of its production.   Some early models use high voltage batteries, so these should be avoided as the batteries are no longer widely available.  Another problem is that many CDV-700’s sold surplus do not work, as they have spent years in storage in damp bomb shelters and were not maintained.   Repair is usually fairly easy, as long as they are in good physical shape and not rusted out or otherwise physically damaged.

Assuming the counter is in good condition, it will still need a few modifications.   For one, the headphone connector is a rather obscure fitting known as a “Single button microphone plug.”  These are not found on many devices anymore and would only allow the original headphones to be used.   Replacing it with a more modern 1/8 or 1/4 inch plug will both allow for modern headphones to be used and allow the unit to be easily hooked up to the sound card on a computer so that it can be calibrated and data logged using available Geiger counter software.   It would also be worthwhile to replace some of the more failure-prone electronics with modern versions that are also more efficient and produce less RF noise.   Finally, a reasonably easy addition would be to add a small amplified speaker so that headphones would not be required for listening.  A speaker with a switch or knob would require drilling in the case, but would not be terribly expensive.  Since the meter would need to be taken apart anyway, it would be worthwhile to paint it to make it look more like a scientific instrument and less like a piece of emergency equipment. All in all, about fifty dollars invested in the internals would produce a very reasonable meter.

That does still leave one problem, however: the probe.   The CDV-700 comes with a Geiger-Muller tube that was originally intended for use after a nuclear war.  It only detects gamma radiation and relatively high energy beta particles.  Even as a gamma detector, it’s not terribly sensitive and thus leaves some to be desired for surveying relatively low background levels.  The probe on the CDV-700 is permanently attached to the unit, but that is relatively easily solved by disconnecting it and adding a BNC connector to the meter and to the end of the probe attachment, thus allowing the original probe or another probe to be used.

The next problem is finding a suitable alpha-sensitive probe to include.   This site has a surplus alpha-sensitive end window tube for only 37.95 plus shipping.  It would be fairly easy to make a probe out of it by using a small piece of PVC pipe with one end open to hold the probe and a BNC connector and cable to connect it to the modified CDV-700.   The only question is whether the tube is available in large enough quantity to make a reasonable number of lab sets.  If not, there may be other probes that can be acquired as surplus.

This approach seems to end up being the most favorable, as it would provide two probes for different types of use and would also give the option to add more probes in the future, possibly even including scintillation probes or other types of detectors.

In the end, the CDV-700 option with modifications and an additional probe seems to be the best one.

So while the $300 price tag seems unrealistic, it appears that a $500 price should be possible for a very well equipped set with an excellent Geiger counter, expandability, a good assortment of sources and a wide range of possible experiments.

Other considerations:

Many of the readers of this blog are from outside the United States.  Unfortunately that could present some problems for shipping radioactive sources, even those small enough not to require a license.   Simply being of very low quantity is not enough to make the sources legal – they generally must also be inspected and approved by the local regulatory body for radioactive substances, although this varies from country to country.   I’m told that shipping to Canada should be just fine and some countries in Europe are probably okay, although each would have to be individually verified.

Other countries may allow the sources but have restrictions on just who can import and sell them.  Spectrum Techniques has a worldwide network of affiliates and distributors.  In some cases, it may be necessary to sell the set without the actual sources and instead have them shipped separately from a domestic distributor in the country of the purchaser.

Interested? It’s expensive, admittedly. Perhaps I could come up with a partial lab or one that could be bought in pieces. I’m still looking into the possibilities. I’m not going to say that I’m definitely going to go for it, but I might. If I get enough interest I may go for it and start putting some of these lab sets together.

And in this case, the same story has gotten a huge amount of coverage, up to 174 articles on Google News as of this posting.

Via News.com.au:

Back up: The future’s close – and it’s really cool
WE could be hooning on Marty McFly-like hoverboards sooner than we thought.

It’s called “quantum trapping” or “quantum levitation” – and it’s real.

This footage shows a magnet, cooled with liquid nitrogen and locked into space.

The display was made by scientist from Tel Aviv at a conference in the US.

Watch as the magnet hovers in place – giving hope to fans of the hit Back to the Future films.

Okay, stepping back for a second. Yes, this is really cool, both figuratively and literally. But it’s not anything new. It’s a great science demonstration that would put any middleschooler in the running for first place at the local science fair, but it’s not new and it’s not groundbreaking.

What is shown here is a superconductor. Superconductors have been around since 1911. They have electrical resistance of zero and this results in some other interesting properties. The first superconductors discovered only displayed the property of superconductivity at extremely low temperatures, requiring liquid helium to get down close to absolute zero.

Type II superconductors, the type which manifest this effect, were discovered in 1954. The effect directly was observed shortly thereafter.

In the 1980’s, “high temperature superconductors” were developed. These still require cooling well bellow normal ambient temperatures, but they can be cooled with liquid nitrogen, rather than liquid helium. The temperatures are much more manageable and some of these materials can even be briefly touched without injury, as shown in the video, although the superconductor itself is probably surrounded by insulation, thus making the surface less warmer than the actual superconducting material.

What is actually being shown is known as the Meisner effect, combined with flux pinning, which it found in Type-II superconductors. Without getting too deeply into it, placing it in the field sets up currents in the superconductor which oppose the field. At the same time, flux pinning causes the magnetic field to become entrapped in the superconductor due to tiny defects in the material. The net result is the superconductor physically resisting reorientation in the field and thus levitating. Flux pinning was the subject of much study involving superconductors in the 1960’s and 1970’s.

More info here. and here.

Superconductors are used in a number of applications, the most familiar being MRI machines, but also in particle accelerators and other scientific applications. In a few instances, superconductors have been used for energy transmission, an application which is likely to expand in the near future.

Meisner levitation, however, has not found many applications beyond being a scientific curiosity. It has been used in a few prototype magnetic levitation transport systems and has been considered for very large magnetic bearings. That is about it, however.

And unfortunately, it would not be very useful for creating a Back to the Future style hoverboard. The primary problem is that it only works in a magnetic field and to keep a human hovering it would need a very strong magnetic field. The magnetic field of the earth is too weak and inconsistent, so the hoverboard would only work at all on a track prepared with powerful magnets. It also might not handle as well as you would want it to. Because it opposes movement against the field, it would not be capable of easily making banking turns or changing in altitude, unless the track it was on was designed to make this happen. It would also resist all turning unless the magnetic field were circular and thus symmetrical in that axis. Moving laterally along the field would be possible, but only along the field lines such that the movement did not change the relationship of the superconductor to the field, which would preclude turning entirely. Also it would be difficult to actually get it out of the magnetic field once you’re done riding it, unless the magnetic field could be somehow turned off. The amount of force needed to make it turn, bank or move across the field would be at least as great as the amount of weight the board could carry.

Making something levitate independent of a strong magnetic field outside it is not possible by any known means, at least not in the manner it is shown in Back to the Future. The only way of making something actually hoover is by using thrust. It could be provided by rocket engines, jet engines or ducted fans, but regardless, the only way a board could hover is by shooting something out the bottom. Sadly this is unlikely to be viable for a “hooverboard” because doing so would require a huge amount of energy, thus depleting fuel rapidly. It would also make the hoverboard very loud and disruptive to the environment, blowing around everything in sight and, if jets or rocket motors were used, potentially melting the pavement under the board.

There is one work-around for the problem – at least to some extent.  Putting a rubber skirt around the bottom of the hoverboard can contain and thus allow it to float on a semi-contained cushion of compressed air, reducing the need for fuel and avoiding much of the disturbances caused by all that air rushing out from under it.   This is basically how a modern hovercraft works.  Actually, it has been done and hoverboard-like devices based on skirted hovercraft do exist.

Sorry, but in my opinion, it’s not even remotely the same.  You’re not free floating or anything, but sliding around on a big rubber bag.  It’s nowhere near as cool.

An obvious area of debate is transportation, especially in terms of cars versus motorcycles.   There’s no doubt that motorcycles are smaller, with smaller engines and less dead weight being hauled around to carry a single passenger.   They use less fuel than cars.

So are they better for the environment?   The Mythbusters take on this question in an episode that will be airing some time in the upcoming season.

Via the LA Times:

‘MythBusters’ asks: Are motorcycles greener than cars?
A trend is afoot, according to “MythBusters” television host Adam Savage: “People are trading in their cars and driving motorcycles instead because they believe that’s the more environmentally friendly choice,” Savage said in Wednesday’s season opener of the popular Discovery Channel show. “The logic is because motorcycles are generally more fuel-efficient than cars, they burn less gas and thus they must be better for the environment.”

The question is: Are they really? As the MythBusters have done with each of the show’s previous seven seasons, Savage and his co-host Jamie Hyneman set out to test the theory.

Selecting three motorcycles and three cars that represented popular models from the ’80s, ’90s and ’00s, they put the six vehicles through a 30-minute, 20-mile course. Seventy-five percent was freeway driving; the other 25 percent was in the city. Savage drove the three cars. Hyneman trailed him at speed on each of the three bikes. None of the vehicles’ makes and models were disclosed.

All of the vehicles were equipped with portable emissions-measuring systems that took exhaust gases from a probe in the tailpipe and engine information from the engine control unit. The devices determined the vehicles’ fuel economy and emissions profiles while the vehicles were running on the real-world course in California’s Alameda County earlier this year.

The upshot? Motorcycles were indeed more fuel-efficient than cars and emitted less of the greenhouse gas carbon dioxide, but they emitted far more smog-forming hydrocarbons and oxides of nitrogen, as well as the toxic air pollutant carbon monoxide. For the most recent model year vehicles tested — from the ’00s — the motorcycle used 28% less fuel than the comparable decade car and emitted 30% fewer carbon dioxide emissions, but it emitted 416% more hydrocarbons, 3,220% more oxides of nitrogen and 8,065% more carbon monoxide.

The MythBusters’ conclusion: “At best, it’s a wash. Motorcycles are just as bad for the environment as cars,” Savage said on the show. “At worst, they’re far worse.”
…
In the 2011 American Lung Assn. State of the Air report, eight of the top 10 cities for ozone pollution were in California. Los Angeles ranked first.

Despite the MythBusters’ findings, emissions are only part of the story of a vehicle’s true greenness. According to the Motorcycle Industry Council, motorcycle manufacturing requires thousands fewer pounds of raw materials than automobiles. They require less fossil fuel, so they require less energy to pull that fossil fuel out of the ground. They use fewer chemicals and oils than cars. And motorcycles produced today are 90% cleaner in California than they were 30 years ago.

Note to MythBusters: How about a cradle-to-grave life cycle assessment for cars and motorcycles for the Season 9 opener?

It’s definitely a complicated issue, especially when one considers the issue of the actual resources that go into one of these vehicles, what impact they may have in terms of displacing other vehicles and how they are driven. Given the differences in driving habits and engine types and efficiency, it’s very difficult to make a one-to-one comparison between motorcycles and automobiles.

Motorcycles are certainly smaller and have a lot less metal in them. However, motorcycles don’t generally age gracefully, especially if they are driven often and therefore may need more frequent replacement. Additionally, many of those who own a motorcycle feel the need to also own a car, since cars have greater utility and can be used when the weather precludes the use of a motorcycle, so owning a motorcycle does not really displace the resources that go into a car.

Many drive motorcycles primarily for recreation, and in this circumstance, they may not be any help at all. Of course this is not universally true, and those who use motorcycles regularly for primary transportation are not comparable to those who use their bikes mostly for fun. How the motorcycle is driven plays a huge role in the environmental footprint. If it’s used for aggressive acceleration, as might be the cause in recreational use, the efficiency is reduced. On the other hand, when used in city traffic, a motorcycle can have major benefits over a car. Motorcycles can negotiate crowded roads better and thus may spend less time wasting fuel by idling.

All these calculations, however, are based on the presumption that the car and motorcycle are both carrying one passenger. This is usually, but not always the case. If the car is carrying three or more people, it wins in efficiency hands down. Motorcycles usually have one person on them, but can carry two. The ability to more easily carry a second passenger or increased cargo capacity can be added with a sidecar. However, when not in use, the sidecar will increase both drag and rolling resistance, thus reducing fuel efficiency.

And of course, though not directly related to emissions, it goes without saying that motorcycles tend to be less safe. Some might say this is a good thing if it means more human deaths, (though I find such views to be despicable) but it could also mean more energy and resources go to medical care.

Personally I have nothing against motorcycles, and I do not wish for this post to come off as being against motorcycles in general. If you enjoy riding, continue to do so. If a bike works out well for your transport situation, go ahead and get one. But the environmental benefits of motorcycles are just not there. It’s a complicated question, but there’s just no evidence that they have a major net impact on reducing emissions.

Of course, this is not really the case. The plants have undergone numerous upgrades and refits over the years and continue to be upgraded and inspected to maintain high levels of safety. New procedures and new systems retrofitted to older reactors have improved their efficiency and safety beyond what it was originally. Of course, even with improvements, the older Generation II reactors still are not as good as new Generation III+ designs, but none the less, they are perfectly safe and reliable sources of power.

The primary reason why the designs have outlasted what was assumed to be their design life comes down to economics. While it has become cheaper and easier to extend the life of reactors, it has also become much more difficult to build new ones. The original designers might have presumed that after twenty or thirty years, their designs would have been so far surpassed that new power plants would have made them obsolete and redundant.

Unfortunately, they had not counted on just how difficult it has become to build a new reactor.  Just getting the permits to build a new nuclear reactor can take upwards of a decade, and a combination of political lobbying, lawsuits and other tactics by special interest groups meets a potential reactor operator at every step of the way, possibly even derailing plans completely before construction is completed but after billions have been spent.   There exists no other facility whose construction will be opposed by so many with so much effort at so many levels.   Paperwork costs alone can top the hundreds of millions, and final costs for construction have skyrocketed since the 1970’s.

Thus we have what we have and their life is extended to the maximum possible since replacements remain so difficult and expensive to built.

This does not mean that they are unsafe.  In fact, there are many examples of technology lasting far longer than its designers had anticipated.

Reasons why something may outlast its original design life:

• Upgrades, overhauls and life-extension modifications may be made during the life of a piece of technology for the purpose of extending the lifespan.   This is especially useful when the limit of the service life is due to one specific part which can be replaced.   Modifications and upgrades can also address systems which become technically obsolete.  It is common practice to preform a mid-life overhaul on navel vessels which includes refitting them new electronics and weapons systems.
• The original design life may have been overly conservative.   This has turned out to be the case with some aircraft.   For example, the first generation of jet airliners were overbuilt and the number of flight hours they were anticipated to be capable of was extremely conservative due to the fact that there was little experience with extended operation of such aircraft.   However, with more experience and testing of the systems, it has become apparent that they can be safely flown beyond their original anticipated service lifespans, as long as they are properly maintained and inspected.
• New technologies may allow the service life to be extended in ways that the original designers could never have anticipated.  For example, in cases where metal fatigue is the limiting factor, new methods for remediation, such as bonding of compost reinforcements to metal parts or ultrasonic peening have been developed.   These may not have even existed when the original service life estimates were made.
• The way in which a piece of technology is used may differ from how it was originally expected to be used, sometimes resulting in decreased loads and stresses and thus increasing the lifespan.   For example, the Boeing 707 has an estimated service life of 30 years before the airframe needs to be replaced or completely rebuilt.  However, that figure is based on airline service, which results in the aircraft making hundreds of flights per year.   Military variations of the 707, though based on the same airframe, spend the vast majority of their time on the ground and only fly for occasional training missions, combat duty and ferrying supplies.   Since the limiting factor for aircraft is flight hours, the 30 year estimated lifespan does not apply and military aircraft can last much longer.
• The design life may not actually be based on the technical limits of a system.   Often, the anticipated life of a technology is not due to the fact that it won’t be usable after a period of years.  It may also be presumed that it will become less economical to provide necessary service, but this is not always the case, especially when new technology makes servicing easier.   The Eiffel Tower is an example of a structure whose design life was not the result of any technical limitation.   It was intended to stand for the 1989 World Exposition, after which it was considered to no longer be needed.   Original permits stated that it could not be left standing for more than 20 years after construction.   This was not because it was expected to be structurally defiant, but many feared it would be an eyesore and that the structure occupied valuable real estate.   Of course, this was not the case as the Eiffel Tower quickly became a beloved structure and even a symbol of the French nation.   Thus, the original plans to remove it were withdrawn.  In other cases,  new missions or purposes may be found after the original is complete.   For example, many Liberty Ships were retired from military sea-lift operations and went on to be used for private cargo shipping companies.
• The design life may be based on the presumption that a newer, better system will come into existence and thus make a design no longer needed.   This is not always the case.
• It may be desirable to continue to operate something even after it has reached the point where the necessary maintenance and operating costs are no longer considered economical by the original standards.   This would be the case with classic cars.  The cost of keeping them on the road is significantly more than when they were newer and no longer makes them economically attractive as general purpose transportation, but that’s not really the point.
• It may refuse to die.   Some devices are intended to be used until they fail and then be replaced.  These include things like lightbulbs, vacuum tubes, bearings and various engine components.   However, sometimes, despite being used for many years, they just keep going and going and don’t fail.

Examples of Technology Going Strong Beyond Anticipated Service Life:

The Boeing B-52:
Anticipated: ~20 years
Actual: 45+ years and counting (airframes in service from early 1960’s).  With plans to keep the aircraft in service until at least 2040, it will likely exceed 80 years and may well approach one hundred years of continuous service before it is finally retired.

The Douglas DC-3/C-47:
Anticipated: A few years to ~20 years.  Many aircraft were built for immediate use in World War II and not expected to be used for more than a few years.
Actual: 75+ years and counting.   Remains in regular utility, charter and cargo service – not simply a flying museum.

The Eiffel Tower:
Anticipated: 1-20 years. The tower was built for the 1889 Exposition Universelle. Original construction permits required the tower be dismantled by 1909.
Actual: 122 years and counting. Baring a catastrophic event, it will likely remain in place for many years to come.

The MS Stockholm/MS Athena:
Anticipated: about 20-30 years (based on similar vessels of similar vessels service life)
Actual: 63 years and counting, the MS Athena is one of the oldest ocean-going passenger ships in regular service.   This is made all the more remarkable by the fact that she was very heavily damaged in 1956 after colliding with the Andrea Doria

Marisat-F2: (Satellite used for maritime and antarctic communications.)
Anticipated: 5 year design life [source]
Actual: 32 years (the satellite was still functional, but engineers believed one of the subsystems was on the verge of failure. The satellite was therefore deactivated and the last remaining fuel was used to place it in a “graveyard orbit” in 2008.)

Mars Exploration Rover Spirit:
Anticipated: 92 days (90 mars days)
Actual: 2269 days

Mars Exploration Rover Opportunity:
Anticipated: 92 days (90 mars days)
Actual: 7.4 years as of publication and counting

The Hubble Space Telescope:
Anticipated: 13 Years [source]
Actual: 21 years thus far and expected to last at least 25 years, though NASA is hopeful it may continue to operate even longer. Hubble benefited from a series of service missions by the Space Shuttle, the last being in 2009. With the end of the Shuttle program no more are planned, though NASA has not ruled out the possibility of future missions using another platform, possibly robotic.

South Pole Station Geodesic Dome Shelter:
Anticipated: 15 Years [source]
Actual: 28 Years – When the dome was finally retired in 2003 it was still structurally sound, but had been replaced by a newer modular station habitat that provided enhanced capabilities and capacity.

World War II “Liberty Ships”
Anticipated: 5 Years (official ship service life requirement) [source]
Actual: 30+ Years. Only two liberty ships continue to operate at sea (both are museum ships). However, after the end of World War II, hundreds of Liberty Ships were sold surplus and were used as general purpose cargo vessels by various shipping lines. They were also modified for military and government uses into the 1960’s.  As cargo vessels, a number of World War II era liberty ships continued to serve well into the 1970’s.

The Parkes Observatory Radiotelescope
Anticipated: About 20 years [source]
Actual: 50 years and counting.

The NASA Crawler
Anticipated: Constructed for the life of the Apollo Program.  Originally anticipated as up to 20 years, but actually 6 years (9 years if Skylab and Apollo-Soyuz included)
Actual: 46 years and counting.  The crawler was built to allow transport of the Saturn-V from the VAB to the launch pads.  After Apollo, it was used for Skylab, Apollo-Soyuz and later to transport the Space Shuttle.  Now that the Shuttle has been retired, the crawlers are no longer actively used, but they remain in storage and are expected to be used for whatever the next heavy-lift launch platform might be, assuming that ever happens.

The “Centennial Light Bulb”
Anticipated: 150-1500 hours (source)
Actual: 110 years and counting.  Early carbon-filament light bulbs typically burned out in a few hundred hours of use.   They were known to sometimes last much longer.  Their high resistance and relatively cool operating temperature can contribute to much longer periods of use beyond the typical 1500 hours.   However, the light bulb hanging in a fire house in Livermore California has been lit continuously (except for a few power failures) since the turn of the 20th century.   The bulb has reportedly gained resistance over the years, due to the degradation of the filament.   Originally it was a 60 watt bulb, but now is much dimmer at an estimated 4 watts.   Yet, most bulbs would have suffered a complete failure of the filament long ago.  Nobody is entirely sure why this particular bulb has outlasted all others.

An old post in a similar spirit: When Old Does Not Mean Obsolete