Although the winter for much of North America has been mild this season, in Alaska it has been extremely harsh.  While those who live in the more remote parts of Alaska are used to dealing with the extremes of nature, this year they are facing the prospect of being cut off from vital supplies of fuel due to the extent of ocean icing and the harsh weather that has made even airlifting of fuel problematic.   This is not the first time these settlements have faced these kind of fuel problems, and it’s not likely to be the last.   In the past, there have been close calls and times when distant Alaskans have been left without fuel for periods of time.  Yet each time this happens, there is always the possibility that remote villages will suffer or even lose lives.

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.

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When spacecraft are sent to explore the inner solar system, solar cells are usually the choice to provide power.  However, when venturing out past the orbit of mars, the intensity of sunlight available makes it increasingly difficult to obtain sufficient amounts of power.  Past Jupiter, it’s virtually impossible to power a space probe with solar cells as they would need to be enormous to gather enough sunlight.   Even within the inner solar system, where sunlight is reasonably intense, solar cells provide limited energy for probes that explore the surface of planets, such as the mars exploration rovers.   Sunlight is also problematic for places like the earth’s moon, where spacecraft would sit in complete darkness for days.

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.

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Background:

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.

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An interesting story has recent come out about research at the Lawrence Berkley National Laboratory has been making the rounds.   It seems some studies relating to the cellular-level effects of ionizing radiation have found the effect is….. GASP…. not linear and directly proportional to dose level.

Via HealthCanal:

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When nuclear fission was first discovered in the laboratory, in 1938, it was seen as a relatively strange reaction, resulting from humans taking a sample of the heaviest known element and shooting artificially-generated neutrons at it until some of the atoms absorbed a neutron and split.   While the experiment provided enormous insight into the nature of atoms and helped provide early confirmation of Einstein’s Theory of Relativity, by demonstrating the release of energy from an observable change in atomic mass, it was regarded as something that occurred in the laboratory.

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.

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The big Atlas rocket has rolled out of the Vertical Integration Facility and is now on the launch pad, payload checked and stowed and systems being checked.  Tomorrow (the 26th of November) it will lift off with the Mars Science Laboratory, a new rover bound for the red planet with plans to land on the red planet in August of 2012.

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…

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Between 1949 and 1951, the company Ac Gilbert produced and sold the “Atomic Energy Lab,” a kit of nuclear and radiation-related experiments intended for use by children in the same way that chemistry sets are used.   The kit included a sample of uranium-238, a Geiger counter, cloud chamber, spinthariscope and some other items used for educational experiments with radiation.  It also included at least three small radioactive sources.   It was modestly successful, likely due to the rather steep price of the set – $50, which would be equivalent to about $460 today.  (about 325 EUR, 285 GBP, 430 AUD)

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.

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Every once in a while I read a story about some technology or discovery that the writer seems to think is new or some kind of breakthrough. This is one of those cases.

Here’s the video that started this all:

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.

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It’s an age old question:  What’s better for the environment?  Smaller and less prone to consuming fuel or large and more sophisticated and controlled.  Many seem to think that smaller is inherently better and advocate everything from smaller power plants to smaller farms, and in both cases, more of them.

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.

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Much to do has been made of the fact that the majority of nuclear plants in the United States are scheduled to operate beyond the initial operating period that was estimated when they were first constructed. This all seems to have started when the Associated Press “broke” the story, despite the fact that it had never actually been a secret at all. None the less, many followed reporting how plants were being stretched far beyond the expectations of what their designers had intended, exposing the public to untold risks as they rust and fall apart.

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:

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