Every Day is Science Friday

Add ‘cheap, effective water filter’ to the growing list of uses for banana peels. A recent report in the ACS’s journal Industrial & Engineering Chemistry Research says that using minced up banana peels is highly effective way to remove copper, lead and other heavy metals from water. Other methods of removing metals left behind from mining, farming and industrial waste can be expensive and often involve their own hazardous chemicals. The scientist’s work involved testing a number of plant waste materials as water filters including coconut fibers and peanuts shells. They found banana peels held some particular advantages:

The researchers found that minced banana peel could quickly remove lead and copper from river water as well as, or better than, many other materials. A purification apparatus made of banana peels can be used up to 11 times without losing its metal-binding properties, they note. The team adds that banana peels are very attractive as water purifiers because of their low cost and because they don’t have to be chemically modified in order to work.

[Science Daily] via [Gearlog]

After calling for a coupon for a replacement box, we decided to take advantage of the opportunity to do some kitchen science and try to find these iron filings.
First we tried grind up the crumbs in a mortar and pestle.

We then  tried putting strong magnets in the powder. While some stuck, it was not clear if it was just stickiness and not magnetism, and it sure didn’t look like iron.

We then added water to make a slurry.

Needs more water.

Tried a stack of little rare earth magnets, but still nothing conclusive. We did see some movement in the liquid  when we passed the magnet over the liquid (but could not capture it with the camera), so we were on the right track, but still not satisfied.

Time for the big guns. Out with the blender and more crumbs.
Reduced crumbs to finer powder and added a generous helping of RO water.

Poured into a little plastic container and applied magnet to the outside of the container. After sloshing and stirring around a bit we began to see a dark blob form on the inside of the container against the magnet.

The blob is made up of small particles and moves with the magnet. Iron!




A little careful arrangement of magnet, camera and window light and (despite imperfect macro focus) we are finally able to clearly see the spiky little iron filings standing up on the side of the container.

Yummmm . . . enjoy your breakfast.

Pi day (March 14 or 3/14) rapidly approaches once again. Last year we celebrated with . . . a pie. This year we are going to be in Minneapolis for my son B to play in a state piano competition, so I was not sure how we would recognize the day short of buying some pie. But now, salvation! Make: TV is having a Make: Day at the Science Museum of Minnesota.  We are SO there. As a subscriber to Make magazine, and the Make philosophy I often lament that all of the Maker Faire events take place in far off Texas or California, so I am very pleased to be able to attend a Make event right here in my home state of Minnesota, and even on a day when I will be driving to the Twin Cities anyway.

Celebrate the ingenuity and inventiveness in our community. Make: television, Geek Squad® and the Science Museum of Minnesota join forces to create a new event giving local engineers, artists, tinkerers and inventors the opportunity to showcase their DIY creations to museum visitors.

This family-friendly event features arts, electronics, musical performances, green technology, crafting and more!

Happy Pi Day!

The Many Faces of March 14

Over at Gizmodo they have the most impressive guest blogger I have seen yet – the Phoenix Mars Lander itself! Click over to read its two current posts:

• Phoenix Mars Lander Looks Back on its Re-Birth
• This is What Landing On Mars Feels Like

Includes a lot of interesting technical information and background on the lander, and a few “personal” insights:

One of the most common questions I’m asked, and one of the most difficult to explain, is whether I knew going in that this mission would cost me my life. The answer to that is yes, of course, and there’s not a single robotic explorer in our solar system that doesn’t know it faces the same fate. Unlike all of you, most of us can’t go home again.

LINK: Phoenix Mars Lander: NASA’s Phoenix Mars Lander Guest Blogging on Giz

This is how the magnets are arranged in a Halbach array:

It does not matter which way N or S is and long as you are consistent to the diagram.  It is not intuitive (to me anyway) but it turns out that this arrangement combines the magnetic flux along one side for a much greater force, while nearly canceling the pull on the other side.

“The diagram (below) shows the field from a strip of ferromagnetic material with alternating magnetization in the y direction (top left) and in the x direction (top right). Note that the field above the plane is in the same direction for both structures, but the field below the plane is in opposite directions. The effect of superimposing both of these structures is shown in the figure at the bottom:” ^Wikipedia

Here is another nice diagram that shows how the arrangement combines the flux of the different magnets.

The above diagram is from an excellent article entitled Build a Halbach Array which details the construction of a simple Halbach array using a wooden bock and Neodymium-Iron-Boron cube magnets. They point out how hard it is to push the magnets into position as they will always want to flip over and align N to S poles, hence the need for the wooden block and glue.

Halbach arrays can also be constructed in several cylindrical forms which turns out to be very useful for brushless AC motors, magnetic couplings and magnetic bearings.

You can learn more at Halbach Array which includes the customary Wikipedia complement of images, diagrams, formulas and links.

There is also a nice set of links at Halbach Array links

Now you know…..

Nobel Laureate Leon Lederman sets up a table on a busy city street corner and offers expert answers to the public’s science questions.

Oh what shame, this senseless tragedy could have been easily avoided if only they had taken simple precautions. Just one little fence, that’s all it takes . . . oh the humanity. . . when will they learn?

Link ScienCentral via BoingBoing

Most of the futurists I read focused on the rise and fall of governments, and especially, the progress of technology and the sciences. The future of art and literature got short shrift, as did sex and religion. At first, I thought this was because too many of the predictors considered their readership to be drawn from the business community. But that didn’t wash: an accurate prediction of fashion trends, or societal attitudes towards sex, would be immensely valuable to any savvy investor or corporate type. Would-be prophets avoid arts and entertainment because they seem too difficult to pin down, too trend-driven. Science provides the illusion that progress occurs in an orderly fashion…

As I immersed myself in futurism, I waded through promise after promise of electric cars, unified world government, and videophones. (For decades, certain favorite predictions have been coming along Real Soon Now.) But before I burned out on days of future past, I resolved to grade leniently. If a prediction seemed to be mostly correct, even if it mangled some details, I gave the futurist credit. If they correctly described the effects of a technology but misunderstood the mechanism of it, that was accurate enough for me.

Welcome to the Future

Addition:

One often overlooked future prediction comes from rock star and writer Pete Townshend. His failed and then reborn 1970′s rock opera project Lifehouse featured people living in a world where pollution is so bad they are forced to stay in Lifesuits and obtain all their experiences and social interaction by plugging in to “The Grid”, a huge global computer network not so unlike today’s internet and social networking sites.

Commenter Bobbie Dawn adds a reference to writer Orson Scott Card and asserts his prediction of blogging in Enders Game makes him particularly relevant to bloggers. I looked him up and, admittitly not having read Enders Game, could not find information on his predictions. I instead found him described as a right wing Bush war supporter and homophobe, not that that invalidates his writing, but it does make me less likely to want to read his work.

He goes on to opine that very recent innovations like computers and nanotechnology are unlikely to be around for a very long time for the simple reason that they are of such recent origin. He says that to find the things that will most like be around in the distant future (like a million years from now), you have to look in the distant past. He claims that concept that old things tend to last and new things tend to fade is a natural outcome of the Copernican Principle which states, in brief, that “you are not special.” This idea original comes from the discovery that the planets do not revolve around the Earth, and that the Earth is not so unique in the Galaxy, but Holt explains that the concept can apply to time as well as space.  He says, “If there is nothing special about our perspective, we are unlikely to be observing any given thing at the very beginning or the very end of its existence.” Holt cites a paper by Richard Gott III published in Nature on May 27, 1993, “Implications of the Copernican Principle for Our Future Prospects” as the pioneer of this reasoning. Applying math to this concept we get that it is 95% certain that we are in the middle 95% of a phenomenon’s existence (and not in the first or last 2.5% or one fortieth.) Considering the example of the internet, which has existed for about 25 years now, we can be 95% certain that that it will continue to be around for another 7 plus months (1/39 * 25) but that it will disappear within 975 years (39 * 25). Using this logic almost everything that we take for granted in our modern society that is a product of the industrial revolution (200 years old or less) will be superseded by something completely new and different within 10,000 years.
I find this fascinating way to look at the distant future, which is always a challenging thought exercise for me to begin with, and even though the hypothesis makes sense it is hard not to cling to the vain possibility that just maybe we could witness the beginning of something really big that will be around a very long time, however unlikely that may be. After all, at some point in history people did witness the creation of written language, or the printed word, and those look to be around in some form or another for quite a long time more. Or even more likely, that we are witnessing the end of longer lasting technology in the near future. I decided to calculate a few examples for myself to get a better handle on this idea. First, the incandescent light bulb. If we consider the first commercially available light bulbs were being sold about 125 years ago, we calculate that they will continue to be available at least another 3 plus years, and not more than 4875 years. Assuming we are near the end of its life rather than the beginning, the 3 plus years looks pretty realistic right now with the surging growth in fluorescent and LED lights. Next, let’s look at the Cathode Ray Display Tube, first commercially available about 85 years ago. Doing the math we come up with a continued life of at least 2 plus years, and not more than 3315 years. Again assuming we are near the end of its life the 2 plus years sounds about right with flat screens taking over. An interesting analysis without a doubt, but the problem I have is that if we were doing this in 1923 when the first CRTs had been available for just 1 year, we would get a life of not more than 39 years, which of course is not in line with the reality we have witnessed. So applying this principle to new inventions is a much riskier proposition, as some new inventions may last longer than 39 years (although not necessarily close to 1 million) and the tricky part is of course figuring out which ones have a future ahead of them, and which don’t. I guess that could be the “95% certain” part of the formula. It would also seem that the algorithm may gain accuracy over time. Or maybe I should be looking at slightly broader categories like “electric lighting” instead of the incandescent bulb.
So back to Holt, if we are adhering to this Copernican principle of the future, what will be around a million years from now? The two, perhaps unexpected, examples Holt offers are numbers and laughter. His main argument for this is that we share both laughter and a sense of numbers with other species, and therefore with common ancestors that have been around for millions of years. He offers a number of bits of data (that I won’t repeat here) as evidence of laughter and an understanding of numbers in a variety of species. What is interesting is how he supposes even these things may change (or not) in our perception over time. Pointing out the current popular view that numbers seem to be timeless, while humor is an ever moving target, he gives the example of Carl Sagan’s science fiction novel Contact where aliens beam a series of prime numbers to earth to establish contact, he offers that if the aliens beamed their jokes at us we would not be able to distinguish them from the background noise, “indeed sometimes we can barely distinguish the jokes in a Shakespeare play form the background noise.” But he goes on to offer a very different view on these two phenomena.

“We are confident that a civilization a million years more advanced than our own would find our concept of numbers intelligible (and we, theirs), but our jokes would have them scratching their heads in puzzlement. That is how we see matters at the moment. In the Year Million, though, I think the perspective will be precisely  the reverse. Humor will be esteemed as the most universal aspect of culture. And the number will have lost its transcendental reputation and be looked upon as a local artifact.”

His reasoning is that although the content and specifics of humor change over time, the underlying principles of what makes something funny, like incongruity (seeing something used outside of its expected context) remain the same over the ages. Indeed, with some analysis I have more than once seen it demonstrated that most plot lines from modern sit-coms can be found in some form in Shakespeare or in even older stories from the oral tradition or Sagas. I would guess that watching a “formal” or “uptight” character (however that is defined by the times) slip on a banana peel and fall will be as funny to my great great grandchildren as it was to my great grandfather in silent movies. On the other hand we have prime numbers. He adheres to the opinion that they are not the “inexplicable secrets of creation” as mathematician Don Zagier declared  in 1975, but instead obey a law that we have just not found yet, as put forward in the Riemann hypothesis in 1859. And while some (like Paul Erdos) have claimed that it will be “another million years” till anyone can cracks the pattern, Holt offers that the Copernican principle yields a much shorter esitmate. The Riemann conjecture was posed 149 years ago, so we can be 95% certain it will survive at least another 4 years, but that it will be solved within the next 6000 years, well short of 1 million years.  Assuming this holds true, when the mystery is solved will they seem as trivial as a game of tic-tac-toe?
So Holt puts forth eventually the transcendence of numbers and the temporary nature of humor will trade places, with humor becoming one of the most universal categories of all. Even if the details change, we will still laugh when an incongruity is solved in a clever way – “perhaps even when a proof of the Riemann hypothesis changes what is today regarded as the hardest problem ever conceived by the human mind becomes a somewhat broad joke, fit for schoolchildren.”
While I find the humor and numbers theory intriguing, I am personally more drawn toward trying apply the Copernican principle to different technologies, both broad and narrow, and in my own way repeatedly attempting to test its validity against the limited real world data available to me. Admittedly a possibly fruitless exercise, but still certainly better than spouting off about the personal jet packs and flying cars we will all be using by the year 2000….

Here is a Zoom:

This is really amazing, or as the Planetary Society puts it, “a speeding bullet photographed by a speeding bullet.” I wonder if they knew they could do this successfully, or if they pointed the camera, hoped for the best and just got really lucky. Either way, very cool!

Here is a shot from NASA showing the lander on the surface, again from the Orbiter

[Link to OMG!! Parachute!!!! Photo!!!!!]

NASA Phoenix Lander Home Page