Earth to Rosetta, Time to Wake Up

After napping for a little over two years, the European Space Agency’s Rosetta is ready to stretch her…panels. On the 20^th of January this year the ESA held a competition to see who could issue the best wake-up call to the hibernating spacecraft. While I don’t know who won I do know they are quite lucky, as they win a free trip to Mission Control in Germany to see what Rosetta discovers.

In 2008 it passed a comet while flying by Mars. While 2867 Šteins had been discovered in 1969, this was the first time clear images of the comet were transmitted and its massive 5.6 km size could be clearly determined. In 2010 she flew by another one, 21 Lutetia, once again transmitting crystal clear images of an asteroid discovered in 1852. How was it discovered in 1852 with the limited technology available you ask? Probably because it’s over 1,000 km in diameter. That’s astronomically huge! (pun intended)

What makes this spacecraft so unique an sets her apart from other satellites is that Rosetta is the first one to be powered solely by solar technology! As it hibernated during its orbit around the sun to gain momentum its instruments were powered down in order to conserve energy. But while it was powered down it was gaining energy from the sun by gathering it on its massive solar arrays. Hopefully this will give Rosetta the extra “umph!” she needs to survive her mission out in deep space where she will only receive 4% of the sun’s power.

It’s been awhile since we’ve flown out into the deep reaches of space here at To Infinity And…In Theory. So let’s strap on our rocket boots, throw on some Elton John, and climb aboard the red eye to see what Rosetta and her little buddy Philae the Lander have in store for scientists at the ESA.

Comets, Asteroids, and Meteoroids

Yay! We get to start with terminology. I know what you’re saying, “my favorite…” but it’s important to understand there are very important differences between comets, asteroids, and meteoroids. The only reason I do this is because technically these words aren’t really interchangeable like so many others in Astronomy. There are a few key variances.

Let’s start with a comet.

Quite possibly one of the most well-known comets is Halley’s. It was discovered in 1531. Then discovered again in 1607…and again in 1682. It wasn’t until a man named Edmond Halley dug through the various reports of these sightings that he came to one very important conclusion. This comet was the same one. He also predicted that it would come back in 1758. While he didn’t live long enough to see that he was right, plenty of other astronomers did, which led to this comet being named after him.

So what makes a comet a comet? A comet is defined as a relatively small solar system body that orbits the Sun. When close enough to the Sun they display a visible coma (a fuzzy outline or atmosphere due to solar radiation) and sometimes a tail. But what creates the tail on a comet?

As it passes by the sun (which as we know is pretty darn warm…) it begins to burn gases and ice off the surface of the orbiting rock. These superheated gases trail behind the asteroid, sometimes miles long, as it rockets through space. This is what turns the space rock from an asteroid into a comet.

Speaking of asteroids, let’s talk about those next.

That’s Ceres. I know, I know, you’ve seen Armageddon and you’re saying “woah dude, that isn’t an asteroid, that’s totally a planet.” Well you’re half right. It was discovered in 1801 by Sicilian astronomer Giuseppi Piazzi. Originally he thought it was a comet but upon further observation it was determined that it was indeed a planet. Well…a dwarf planet. (They prefer to be called “Little Celestial People”) But seeing as it floats within the asteroid belt, it’s earned its moniker as an asteroid.

Asteroids are small solar system bodies that orbit the Sun. Made of rock and metal, they can also contain organic compounds. Asteroids are similar to comets but do not have a visible coma (fuzzy outline and tail) like comets do. It floats happily between Mars and Jupiter and actually contains one third of the mass of the entire asteroid belt. (Once again…huge) That’s not to say that if it broke orbit and passed close enough to the sun it couldn’t develop a tail, after all, the surface is believed to be made of dust and ice, perfect conditions to grow a coma. However that scenario is quite unlikely considering it’s been content with its lot in life to this point.

The third space rock type we’re going to talk about now is the Meteoroid. This particular floating stone actually has three forms like a Dragonball Z villain. Meteoroids are the first stage, Meteors are the second, and Meteorites are the last. We’ll break down all three in the next section.

A meteoroid is a small rock or particle of debris in our solar system. They range in size from dust to around 10 meters in diameter (larger objects are usually referred to as asteroids). But don’t mistake their smaller diameters for cute and cuddly. Once they enter the atmosphere of Earth they become known as a Meteor. Most of the time they’ll burn up in orbit, but as the blast in Chelyabinsk, Russia in February of last year showed us that’s not always the case.

Once a Meteoroid enters our atmosphere and becomes a Meteor about to cause an impending strike it is officially classified as a Meteorite. The effects of a Meteorite impact can be devastating, equivalent to several nuclear megaton blasts. (Time to call in Bruce Willis) That’s why NASA’s new Near Earth Object monitoring program is so important so we are able to identify threats like this long before they enter our atmosphere in the future so we don’t end up embedded in the crust of the Earth next to the dinosaurs.

So why am I telling you all this? Because the ESA is looking to land on a comet and it’s important to know the extreme challenges they face in doing this. Comets slingshot through the solar system gradually gaining speed as they play off the gravitational forces of the bodies they orbit. Asteroids like Ceres are essentially locked in orbit unless a huge impact was to send them rocketing out of alignment. (Typically that’s how an asteroid becomes a comet or a meteoroid)

Next we’ll talk about the challenges the ESA faces, how they intend to overcome them, and what they expect to learn from this unique mission into the far reaches of space. Let’s start with the biggest one of all, how exactly they intend to make contact with this orbiting mass. The details are far more intricate than you may think.

Space Darts

We’ve all played darts, but space agencies around the world have adapted the game to a whole new level. Think of it like this. When you look at a dart board you select the spot you want to hit. You close one eye, pull your arm back, take a couple practice swings and release it. If you’re experienced, nine times out of ten you hit what you’re aiming at.

Now imagine that dart board is several million miles away. It takes more than closing one eye and a deep breath to hit what they’re aiming for. It takes a series of complicated mathematical equations, physics, and a whole plethora of very expensive technology. Luckily, the ESA has all three down to a…well…a science.

When Rosetta was initially conceptualized in 1993 they were aiming at a different dartboard altogether. Comet 46 P/Wirtanen was caught in the crosshairs but due to postponements and complications with the rocket Ariane 5 ECA they switched it up. So in 2004, when Rosetta was launched its new target was designated 67 P/Churyumov-Gerasimenko.

But in order for Rosetta to “dock” with this comet certain parameters needed to be met at the outset. First and foremost speeds have to be matched. But 67 P/Churyumov-Gerasimenko has been orbiting for a long time. It’s had thousands upon thousands of years to gather the speed it moves at. Unfortunately, we don’t have thousands of years to follow it in orbit trying to play catch up. So how are they going to dock with it?

Through a process called a Gravity Assist Maneuver or Gravitational Slingshot. What it’s doing is moving around the sun and using its gravitational mass in order to gain momentum. The process can be used to accelerate or even decelerate depending on the arc of the object in motion. During its approach vector it makes a wide loop first, then, in order to garner further velocity, the orbit gets smaller and smaller on each approach until finally it’s commanded to break free toward its target.

Think of it in terms of a tether ball. The ball tied to the end of the string in this analogy would be Rosetta; the pole that the string is attached to is the sun. When the ball is struck hard enough it makes a lazy, slow loop around the pole. As the string gets shorter and shorter the speed at which the ball is moving begins to increase until it reaches its terminal velocity. If the ball were to be released from the string it would rocket off in the direction of its trajectory until outside factors like gravity and resistance pulled it down.

However, as we all should know, the voids of space have no gravity or atmosphere; therefore there is no resistance to slow the object down until it enters the gravity of another celestial body. Because of this the object maintains its velocity and is able to quickly get up to the speed of its intended target. But this is just the first problem the ESA has to overcome, the second one, believe it or not, is far more difficult in comparison to that.

The gravity on 67 P/Churyumov-Gerasimenko is a million times less than that of Earth’s. In other words, one wrong step and you’re floating off into deep space. (Yikes!) This poses a huge obstacle to the European Space Agency in getting Rosetta’s lander Philae to catch a piggyback ride through space.

With the gravity being so low on the surface of this comet one misstep could destroy over two decades of hard work and effort. Because of this Philae was outfitted with some special equipment to help it “stick” to the comet. Two harpoons will inject themselves into the surface to anchor it in place. Philae has also been equipped with self-righting landing gear to make sure he doesn’t tip over and once the feet make contact they will drill into the surface, further ensuring this multi-million dollar piece of tech doesn’t just fling off into space.

Outfitted with several different instruments including radio-spectrographs and sub-surface drills to take samples of the rock to determine the composition, this may be one of the most ambitious projects launched in recent years. But what exactly are they intending to learn from this mission? Would you believe me if I told you they’re looking to answer the question of where we came from? I hope so, because it’s basically the goal here.

But how exactly will some barren ice rock in space tell us where the complicated diversity of life on our planet originated from. Glad you asked. Let’s briefly explore that next in our final section today.

From Space Rocks to Building Blocks

Comet’s, Asteroid’s, and Meteoroids are all capable of containing a variety of materials. Certain classes of the space rocks contain mostly metals, some have been found to be highly dense carbon (diamonds), and some are even stranger still, because they contain organic compounds. If you don’t know, we’re organic compounds, and if you subscribe to the theory of evolution such as I do, then you know we all evolved from single celled organisms that likely were transported here by these tourists of the solar system.

Our planet didn’t start out as a planet. It started out as superheated gasses that formed into heavy elements. As gravity pulled those elements together it formed a solid mass. That solid mass slowly became heavier and generated more gravity and passing comets, asteroids, and meteoroids were pulled into its gravity. That is how we ended up with such a diversity of elements on the planets in our solar system…well, theoretically anyway.

But if some of the bacteria and organic compounds hitching a ride on the backs of these objects survived the entry into atmosphere that would certainly explain how we got here. That’s why landing on this comet is so important. By studying the subterranean composition of it and the formation of its coma as it passes the sun it will give scientists a much clearer understanding of exactly how comets play into the evolution of our solar system.

Philae is expected to make its daring descent onto the surface of 67 P/Churyumov-Gerasimenko later this autumn. I’ll be following this mission closely in the news and when new information develops I’ll be sure to write a follow-up blog on Rosetta and Philae. Until then, good morning, good morrow, and Godspeed Rosetta. I hope you enjoyed your nap, because now it’s time to get down to business.

-       Ryan Sanders

Thanks as always for reading and be sure to share this on Twitter, Facebook and Reddit and EVERYWHERE ELSE! J You guys and gals continue to make this one of the most enjoyable and ambitious undertakings for me to write and I hope they are just as enjoyable for you to read. Comments, questions, or corrections are always welcome so feel free to post them below. For further reading you can follow-up on any of the links listed below. Happy learning everyone!

-       Phys.org article on Philae Lander

-       Wiki entry on Rosetta

-       ESA overview of the entire mission, goals, and instruments

-       Information on the Chelyabinsk blast in Russia early last year

-       Space.com article on many unique facts of Halley’s comet

-       More information from the ESA on 67P/Churyumov-Gerasimenko

-       Information from NASA on Rosetta

Steel Yourself. Silk Worms Are Spinning the Army's Armor

Silk is a highly sought after, gloriously soft fabric. For centuries it has made its way into the hands of artisans, courts of kings, and closets of the rich and famous. But where does this substance come from? For those of you who get squeamish around entomology you probably aren’t going to like this, but you’re technically wearing worm juice. More technically its cocoon, produced in the salivary glands. In other words, spit.

There are a few kinds of silk worms out there but the one that we’re going to be talking about today isn’t one you’ll find in the wild. In fact, most silk worms that are harvested are usually called Bombyx Mori, or domesticated silk worms, so it’s rare you’d find those in the wild either. Although if you find one of these guys pictured above and it has red eyes, you might want to contact University of Wyoming, and quick. You may have a body armor builder on your hands.

So what’s so special about worms and silk? Well I’m glad you asked. Researchers at University of Wyoming are currently marketing a new kind of silk. Well, it’s not a new kind of silk, so much as it’s a new way of spinning it. Using genetics scientists have found a way to splice in the genes that produce Dragline silk in spiders, into the genetic structure of worms. (We’ve talked about genetics a little bit before here at TI&IT. You can read the past article “PhotoshoppingDNA: The Art of Molecular Editing”)

Now this may not sound like such a big deal until you find out that harvesting this silk in mass quantities from a spider isn’t an option. We’ll talk about why they can’t do that today, as well as these neat little pet worms that blossom into beautiful Silk Moths. We’ll also break down the how and why of their silk spinning abilities, a little bit about the history of silk, the reasons they don’t use goats to produce steel thread (Yes…you read that correctly) anymore, and the crazy little proteins that would make Spider-Man drool.

That’s One Shiny Loincloth

Okay, so that’s not a loincloth, but it is really old, and at one time if you had held it up to the light, it would have had a shimmering effect like a diamond. Back then they probably chalked the phenomena up to the Gods…or something else along those lines as the reasons this happens would not have been understood. (And if they were nobody decided to share it.) But however they figured out it occurred it certainly wasn’t divine intervention.

What the effect actually is attributed to is very similar to gem stones referred to as “Cat’s Eye”. It’s called Chatoyancy. While this generally refers to stones cut in a certain way so as to make them more appealing to consumers, it works on silk too. When light hits the surface of the fibers it’s reflected in a triangular-prism format. That’s what gives it the shimmering effect as you move it around in the light.

The oldest silks can be traced back to between 3000 and 4000 B.C.  Do you know where they came from? China of course! For a few thousand years China held dominance on the silk market. That was until the Silk Road opened up and other countries across the world got into the game. Unfortunately though, for the rest of the world silk industry, issues with silkworm disease and production halted the spread of the silk industry across Europe and once again China came out on top.

But how did they figure out that this curious cocoon could be used to clothe the rich and fabulous? According to sources it started with a young Chinese empress named Xi Ling Shi. (Multiple spellings abound all over the Internet) Her palace garden was filled with these trees called Mulberry that silkworms just absolutely adore. Legend says she touched one of the cocoons causing a strand of silk to fall loose. Shortly after the tailors discovered the tensile strength of this textile and decided to put it to use for the royals. Anyone caught in those times smuggling this closely guarded imperial secret was put swiftly to death! (Yikes!)

It wasn’t until the Han Dynasty (206 B.C. – 220 A.D.) that the silk trade really took off. A road was opened up (called the Silk Road by historians surprisingly…) that led them from China to many other nations, starting with Persia and culminating in Europe. They had a hit.

(Land routes are in red, sea trade routes are in blue)

The secret was out. Silk was in. For centuries it dominated the global market’s economy, anybody who was anybody had to get their hands on this strong, soft, pliable material. Its uses ranked from everything to clothing and blankets, drapes and curtains, and many other luxurious items. It took an Empress to figure out that silk was pretty; it took an industry to realize it could make them rich. But how do you get a worm to make something created accidentally as a byproduct of nature by innate self-preservation mechanisms?

                                                                                                    

Make Checks Payable To Wormy, 302 Mulberry Ln.

Left in the wild, silk worms will do their thing. They’ll eat their Mulberry leaves, spin their cocoon, hibernate inside, and through metamorphosis become a flying silk moth. But somewhere along the lines their plans were changed. People began cutting the cocoon’s open, removing the worms, and spinning the delicate fibers into clothing using various machines. Don’t worry about the worm either, they aren’t just thrown away. In fact, most places where silk is harvested, the worms are cooked into various delicacies after de-cocooning them.

If the worms are allowed to enter their moth phase they destroy the silky cocoon on their way out. Proteolytic Enzymes are the reason this happens. It can cause the silk to fall away in strands of random length instead of the cocoon being unraveled as one continuous piece. As you can probably imagine this won’t do for clothing makers. Not only does it shorten the length of the silk strands, it compromises the integrity as well. That’s not good for an industry looking to market silk as some of the most durable stuff around.

Once the cocoon is boiled, de-wormed, and unraveled it’s sent to a machine called a Doubler. This machine does just as the name implies, it doubles the thickness of silk by weaving strands of it together thereby increasing its tensile strength. While silk is strong, it still can break. The Doubler just increases its longevity.

Some of you may be wondering what Tensile strength. Tensile strength just refers to the amount of stress a material can handle before it breaks or snaps. Think in terms of a fishing line, different lines come with different strengths and thicknesses. You wouldn’t go shark fishing with a line rated for Smallmouth Bass. Any kind of material capable of stretching has a tensile strength and, as you can imagine, some are much higher than others.

After the Doubler comes dying the silk. Various Acetic Acid mixtures (found in vinegar) are used to help the dyes bond better to the silk. From there it’s sent to a weaving loom, where it can be spun by a craftsman into a new dress, a soft bed sheet, or even a flowing pair of curtains for your new office room.

(Models wearing dresses spun from fine silks)

But there are other silks out there with higher tensile strengths than that produced by Bombyx mori, (The domesticated silkworm) that are much more highly sought after. Silks produced by the webs of spiders. Yet, it isn’t the clothing industry looking to capitalize on the strong, durable, luxury good. It’s actually the military, and no, not because they want Versace to make uniforms that “pop” and “shimmer”.

Peter Parker’s Haberdashery

Silkworms may have been the first species we commercialized the silk trade through, but Spiders have been doing it better for eons. Spiders produce several kinds of webs. Some are for their internal nests, some are used to catch themselves should they fall, others are used to make the intricate lattices that form their deadly nets, and some are even used to protect their young inside an egg sack. But whatever kind of web the spider spins there is one thing that remains constant. It’s a form of silk.

The strongest silk that a spider is capable of producing is known as Dragline silk. This fiber is so strong that scaled up, it makes Spider-Man seem plausible. (Aside from the radioactive bite to create the acquisition of his powers.) If humans could produce the proteins capable of spinning this material however, and if adjusted for ratios, it would be strong enough to support them. (Think Nylon on steroids)

Dragline silk is used to make the outer connection points for a spider’s web. Because it’s so strong it’s capable of withstanding bombardment from the elements, large prey snags, and constant traversal by our eight-legged arachnids. Some species, such as the orb weaver, have very large abdomens that are relatively weak. They will die if they were to fall from a great height. To avoid this scenario, they use Dragline silk to keep them suspended in the air. Ever seen a spider just dangling there? The fibrous tendril he’s hanging from is what we’re talking about here.

So if it’s so strong, why use silkworms at all? Why not just switch over to using spiders as the main method of harvesting silk? In theory it sounds like a good one but in practice it doesn’t really work so well. See, spiders are extremely territorial, so when one wanders into their neighborhood it becomes a cannibalistic version of the Bloods vs. the Crips. Not a pretty sight. Darn those gangster spiders…

So that rules out spider farms.  

As a result scientists turned to splicing the genes into bacteria. This met with failure. So they tried putting it into Tobacco plants. That didn’t work either. Finally they thought maybe we can put the gene into goats and cows! …I’m sure you can guess that went over like a turd in a punch bowl as well…

Part of the reason it’s so hard to generate spider silk in the lab is that it starts out as a liquid protein that’s produced by a special gland in the spider’s abdomen. Using their spinnerets, spiders apply a physical force to rearrange the protein’s molecular structure and turn it into solid silk. Goats, Tobacco plants, and single-celled organisms can’t do this; they don’t have the biological structure capabilities.

(Spider-Silk “milking” harness)

In 2009, textile expert Simon Peers used 70 people and four years of his life to milk spiders to produce a golden tapestry in Madagascar. While the final result is absolutely gorgeous, (you can read the full article and see what the tapestry looks like here on Wired.) it wasn’t very practical. Nobody wants to wait four years for a rug. It seemed scientists were at an impasse because no other animal had the necessary equipment.

But silkworms do. Silkworms use silk all the time. So if scientists could isolate the right gene for the silk they wanted, maybe they could put it into the body of a worm and it could produce it for them. That was exactly the kind of thinking that led Donald Jarvis, a researcher at University of Wyoming, to this brand new kind of super silk.

Silky Smooth Troops

Because silk is so strong for it’s incredibly miniscule diameters the textile industry wasn’t the only one who wanted to use it. In fact, the military, medical professionals, and architects had their eye on this remarkable material. But before it could be used for these various applications, there first had to be a way to produce it abundantly.

That’s where Jarvis comes in. Using genetics (gotta love genetics) he was able to piggyback the DNA sequence of spiders responsible for creating silk proteins into the makeup of silkworms. Through trial and error they managed to come up with some worms capable of producing various new kinds of silk with even more variable tensile strengths. Just last year this went into production.

But the gene didn’t transfer over to all worms. If there is one thing we know about genes it’s that they are hereditary, which means they are passed on. But not all genes are passed down at once; it seems some of them are selective. (Morgan’s fruit flies anyone?) So how did the scientists determine which worms carried the spider DNA and which ones didn’t?

By using fluorescent dyes they created a mutant worm with glowing red eyes, (that’s a terrifying feature) and used these as an indicator for which ones the gene was present in. After separating the red eyes from the black eyes and breeding them they finally ended up with a stable colony of steel spinning silkworms.

This technology is useful in biodegradable sutures. If you need internal surgery, chances are something inside the body cavity is going to get stitched up. Manufactured sutures, while they can be made biodegradable, still aren’t natural, so harmful chemicals (even though they aren’t deadly ones) get transmuted back into the body. With spider sutures, the proteins will break down naturally and be transformed into other substances the body can either use or safely discard through waste. (Spider poo)

Another particularly interesting use would be for ligament repair. Currently production methods of artificial ligaments are costly, require multiple painful surgeries throughout the patient’s life, and lack the tensile abilities of the real thing. Spider silk on the other hand is extremely pliable, and if woven together into the thickness of a ligament, could require only one surgery to install and last the rest of a patient’s life. Another use they’re looking into is for gauze that can aide in wound healing, (although to be totally honest I’m not sure how that one works.)

While all of these uses will better mankind in the long run, perhaps the shortest-term technological use for this stretchy super string is in body armor.

Currently body armor is bulky, cumbersome, and while it has advanced since the early days of Vietnam, it has a long way to go before it creates perfect protection. Silk is flexible, lightweight, it breathes rather easily and when combined with Dragline Spider-Silk DNA, it’s virtually indestructible. You can see the implications here.

While all these technologies are still in the R&D phase, silk has inadvertently redefined itself and once again is at the top of the pile. Time will tell if we’ll see Spider-men running around the deserts with Orb-Weaver tendons but there is one thing I’m certain of. Science has shown us that silk is much more than just a pretty face.

-       Ryan Sanders

Thanks for reading! If you would like to know more about anything we talked about above in the article feel free to follow any of the links below. Also don’t be afraid to share this around on Facebook and Twitter, and be sure to head over to Facebook and Like To Infinity And…In Theory by clicking here. Thanks again everyone! And happy learning!

-       Phys.org article on spider silk for medical applications

-       Scientific article on the makeup of Dragline Spider Silk

-       Article on spider silk gene isolations

-       Wired article on UoW’s spider silk program

-       Kraig Biocraft Laboratories main website(where spider silk is created for various applications.)

-       Spider cannibalism article from LiveScience

-       Spider silk for ligament repair article from LiveScience

-       Bombyx Mori entry from Wiki

-       History of Silk entry from Wiki

-       Why goats don’t work for Spider-Silk harvesting

Green Energy (Part 2): Just Leaf the Fuel Cells to the Flora

Yesterday at To Infinity And…In Theory we talked about Fuel Cells and their background story starting with the first man to dream them up (William Grove) and concluding with the man who sent them into space (Francis Bacon). If you missed yesterday’s entry don’t fret, you can catch up here. [Green Energy (Part 1): Four Score AndTwenty Years Ago Fuel Cells Were Born! …(ish)] Today we’re going to see how these pioneers who laid the very important groundwork for Hydrogen Fuel Cell technology are pushing the energy crisis out of the way.

After NASA witnessed the hidden potential of these tiny molecular powered batteries firsthand they were ecstatic to say the least. They jumped onboard the Green Tech train and launched some 200 projects using Fuel Cell research as the backbone. Sometimes it only takes one huge influence to boost innovation to invention. Since the 1960’s, laboratories all over the world have delved into these powerful technological marvels of science.

We’re going to talk just a little bit more about their history today (not much, we covered the history pretty well I think yesterday) starting from the bulky models used on Apollo to the silicon sheets half a nanometer thick today. We’ll also talk about how they work, how they charge them up, and a new harvesting technique that could make Fuel Cells the most cost effective energy option on the market to date.

Think you know Green Technology in and out? Well then, let’s put that knowledge to the test shall we.

It’s Not Easy Being Green

When Grove conceptualized the Fuel Cell in the late 1800s I doubt he had space travel in mind. Heck, at that point they barely had a grasp on it. But Francis Bacon’s Hydrox Fuel Cell blew everyone away in the middle of the 20^th century. Yet the technology didn’t catch on, Ford still had a monopoly on propulsion, no one was interested in a product that had not been tested. After all, who in their right mind would want to be a guinea pig?

But NASA saw the promise. (Oh NASA, how I love you. For real.) It launched 200 projects into Fuel Cell technology and sure enough in the late 60s, Bacon’s Fuel Cells, with some slight modifications, made their journey into space a reality. They were also used again in a little project you might have heard of. Apollo, perhaps? Ring any bells? I really hope so because the Apollo program accomplished one of the greatest feats of all time.

Apollo 11 put a man on the moon.

Yep, Apollo 11 was far more important than just the prequel to Apollo 13, (no Tom Hanks here, sorry folks!) it was the mission where Neil Armstrong planted the American flag on the lunar surface. (We really have to stop claiming things that technically don’t belong to us…) But how did this happen? Well there were millions of parts in motion, but an important aspect of the mission was a Fuel Cell.

More importantly, not only was the Fuel Cell capable of splitting Hydrogen and Oxygen in order to produce energy, it could reassemble the molecules to turn them back into water. I’m sure it was filtered, but this is what the Astronauts drank. Hydro Fuel Cell H2O.

So how does it do this? It’s pretty cool actually; I’ll break it down for you.

The Bacon Cell is essentially an Alkaline Fuel Cell, and boy are they efficient. What’s happening is called a Redox reaction. (Red = Reduction, Ox = Oxidation). This can be as simple as oxidation of carbon to yield Carbon Dioxide, or as complex as producing glucose inside the human body, both are forms of a Redox reaction.

Well this concept is happening inside the battery. (A stack of fuel cells). At the anode hydrogen is being oxidized. When this happens it enters its liquid state, water. It then re-enters the module and returns to the cathode where the water is then turned back to hydroxide ions. The cycle keeps repeating itself, thus creating a regenerative supply of energy. The best part of all you ask?

Electricity and heat are the byproducts. That means powering the ship, according to a molecule, is just their waste.

The electrodes are separated by an aqueous alkaline solution. It’s the catalyst for the reaction to produce water and electricity. There’s only one slight problem. If Carbon Dioxide gets into the Fuel Cell it can “poison” the entire system, compromising everyone onboard the ship. (Seen the new Sandra Bullock flick? Being compromised in space is scary stuff!) Because of this both pure oxygen is used and a scrubber is incorporated into the system so as to filter it after each pass. So why don’t we use this for the general public?

The poisoning effect we just talked about is one of the reasons. It can happen fairly easy, and if it does, it’s pretty much irreversible. Considering we expel carbon dioxide as waste from our lungs, we could potentially destroy the vehicle ourselves by just driving it. Ford would love it, but we’d be in the poor house. Pretty much, technology just wasn’t there yet for small, affordable, consumer models, after all, it was only the late 60’s, we didn’t even have Internet yet! (Or Google. What did we do before Google? I think it was like a library or like, something about Dewey…oh well.)

However that reality may not be so far away. In 1999 a transport boat that ran on AFC’s was put into commission. It was called the HYDRA. (Run Captain America!) Before they took it out of the water and decommissioned him he transported some 2,000 passengers and even won a few energy related competitions.

But now Fuel Cells, once again, have come out of the world of obscurity and are back in the spotlight. Yet now they aren’t just being looked at as a replacement technology because we might run out of gas. Now we need them because soon, we might kill the Earth if we keep it up, and running out of a planet is far more treacherous of a prospect then no more driving. At least to me, I don’t know how you feel about it.

So what are we doing to stop this bleak future from occurring? Researchers in Tennessee came up with a clever answer to that question. Let’s see what Popeye has to say about Science.

Eat Your Spinach, Sailor…

If you’re old enough to remember the man pictured above, then your childhood was most likely AWESOME! If not, I’m sorry…anyway. Do you know how Spinach makes the food it consumes? A little process called photosynthesis. Did you also know this produces chemical energy? Huh? Did ya!?

Well this chemical energy can be converted into another kind of energy, something of a kinetic variety. Mechanical energy to be exact, and at Oak Ridge National Laboratory in Tennessee, that’s exactly what scientists are looking to exploit.

It takes light 8 minutes to reach the leaves of the Spinach. In five trillionths of a second the plant is already converting that sunlight into energy. Where Alkaline Fuel Cells were efficient and their obvious replacement Silicon Fuel Cells was more so, the environment’s natural processes have billions of years ahead of us. While we’ve been trying to manufacture artificial versions of Mother Nature, Mother Nature has already created the perfect practice.

So how are they achieving this goal? Turns out you can infuse the leaves of spinach with platinum. Because chloroplast is already a conductor for the plant to make energy with, this platinum just enhances its natural abilities and suits it toward technology we can use. The best part of it all, it’s 100% green.

The platinum turns the spinach leaf into an electrical switch. Biometric scientists are looking toward this technology for use in the blind. It has the potential to be very effective for biotic eyes. Speed-of-light computers are also a potential for the same reason. The human retina registers light faster than anything we can currently build, but by using these platinum chloroplasts, it could provide the building block to make something that not only matches the speed at which the eye operates, but surpasses it as well.

Time will tell but I’m looking forward to this technology in the future. Want to know more about Spinach powered super computers? You can by clicking here.

So by now you’re probably asking yourself, “yeah that’s cool and all, but I thought this was about Fuel Cells.” Well…not that part in particular. But I just wanted you to understand the potential for plant based biotechnology, before I blew your mind. While they had one bionic eye on supercomputers when they were working with University of South Carolina to extract Spinach proteins, they had their other one trained on the future of sustainable energy.

Standing Fern on Green Energy

That complex tangle of green, yellow, and blue is actually fairly important to all of this. It’s called the Light Harvesting Complex, or LHC-II for short. It’s the protein that they pulled from the spinach responsible for the function of photosynthesis. The guys over at Clean Technica break it down the best:

Oak Ridge writer Bill Cabage describes the latest breakthrough as a biohybrid photoconversion system. The researchers were able to confirm that a particular light-harvesting protein derived from plain old supermarket spinach can be induced to assemble itself into a membrane, by putting it into a liquid solution containing synthetic polymers. The protein, called LHC-II (LHC stands for Light Harvesting Complex) interacts with the polymers to form a membrane, which in turn produces hydrogen. In other words the membrane acts as a kind of photovoltaic cell, but instead of generating electricity it generates-hydrogen.
Read more at Clean Technica

In short, clean, renewable, affordable, sustainable, and literally green as you can get energy. There is a catch though. This technology doesn’t come cheap. Platinum is incredibly expensive. But researchers at MIT may have an idea that could reduce that cost significantly.

“Leafing” It All Behind…

As I mentioned before, Platinum is super expensive stuff. Not to mention, it’s fairly uncommon as far as rare Earth elements go. Another problem with Fuel Cells was the ability to keep them self-contained and contaminate free. But that could theoretically be a thing of the past thanks the brilliant mind of Daniel Nocera. Toiling hard night and day in the bowels of MIT, he finally seemed to figure it all out.

He would grow trees that produced hydrogen instead of oxygen.

…

HA! Nope, but I had you going for a second there didn’t I? It might as well be that though considering the principle they operate on is exactly the same as a leaf.

No not the leaf, the thing on the leaf. And no, you don’t have to attach them to a leaf, they are self-contained and operational. No planting required. But the million dollar question is how do they work? It’s not a mystery, it’s just science.

When sunlight hits a leaf it begins to cause a chain reaction. The sunlight begins to convert chemicals within the leaf into free oxygen by breaking down water. That oxygen is then released back into the environment for us to breathe. This is basically how photosynthesis works though there are much more complex things happening, (HowStuffWorks.com will tell you all about it here.) But we should quickly clarify what we mean by “leaf”.

The artificial leaf may be a bit misleading; it’s actually called a Photoelectrocell. Photoelectrocells differ from Photovoltaic cells significantly. Voltaic cells generate voltage when light hits them, while Photoelectric cells generate electricity from light. Voltage determines the electric potential, meaning how much power there is going to be. (i.e 9V batter, 12V battery etc.) A Photoelectric cell converts it into electricity, like a solar panel, and its power is determinative of its capacity and how much energy is available. But anyhow, back to fake leaves.

By using the same basic principles of photosynthesis with only a few slight adjustments, Nocera created the little wafer pictured above to basically do just that. Except instead of producing free oxygen for us to breathe, it breaks down water into oxygen and hydrogen for us to use to power our cell phones, cars, laptops, and robotics. By placing it in a tankard of water (refilled daily) the Photoelectrocell can make all sorts of things happen.

And it’s fairly cheap.

Instead of running mostly on Platinum it uses very little of the precious element. It’s mainly comprised of Cobalt, Zinc, and other fairly inexpensive metals and minerals. The wafer is then coated in a sheet of silicon that is thick enough to better protect the metals from oxidation (rusting is a form of oxidation. Oxidation is what destroys the electrodes.) Yet thin enough to allow the reaction to take place effectively.

But in order for everything to work proper, clean water is the essential ingredient. Testing is currently underway to make one that can survive in slightly more contaminated environments but after a while it still clogs the chip and the process stops working. They also discovered another unique property of this, to a degree the silicon area of the chip will repair itself. Nocera and his team noticed this when they roughed up the surface in an attempt to discourage grime and biofilm from building up on the artificial leaf.

Unfortunately keeping contaminants out continues to be a problem. While a closed cell is possible, water is still needed for the initial catalyst. Clean water at that to avoid degrading the material faster than necessary. Not all parts of the world that could certainly benefit from this technology have ready access to clean water. Plus, in order to keep it cost effective, an open cell where water can continually be refilled is preferable as it wouldn’t have many special requirements that quickly add up to total wallet devastation over time. 

A Green Future (Literally)

As the price of solar technology continues to drop and the mass production of artificial leaves becomes a priority, Dr. Nocera claims we may see this technology in every household worldwide in as little as five years. But if there is one thing I know about the world it’s that the people with money don’t like to let go of it, and major power companies are not going to like this tech one bit.

Because of its potential to be extremely cheap to produce, it would be reasonably priced for the Consumer. If two panels cost $60, and two full size panels (we’re speculating here only) could potentially run a two story house, then pretty much anyone in the world could afford them, even in the most impoverished areas. Let’s face it; it would put Consumer’s Energy out of business and all other power countries worldwide.

Right now it’s estimated that the current cells cost around $6.50 USD to produce. While fossil fuels are sitting pretty at the height of popularity still, Fuel Cells are back. And just like when Grove powered the telegraph and truly became the definition of Avante Garde, they’re in line to change the way we live in this ever developing world.

-       Ryan Sanders

Thanks for reading! And as always if you want to know more about solar powered spinach, wireless Fuel Cells, or the artificial leaf and its creator follow any of the links below. Share it around, after all, everyone loves science!  Happy learning!

-       Nature article on the artificial leaf

-       Clean Technica’s article on the artificial leaf (equally as well written as the above)

-       BBC Horizon video with Daniel Nocera

-       Daniel Nocera’s TEDx talk about sustainability

-       Designboom article on turning grass clippings into solar panels

*Correction: In yesterday’s article I said the technology to turn Spinach into electrical switches was patented in the 1990’s. That was a typo. I meant 1980’s; the actual patent was issued in 1985. Sorry about that folks but mistakes do happen. - Ryan Sanders