Note (12/2015): Hi there! I'm taking some time off here to focus on other projects for a bit. As of October 2016, those other projects include a science book series for kids titled Things That Make You Go Yuck! -- available at Barnes and Noble, Amazon and (hopefully) a bookstore near you!

Co-author Jenn Dlugos and I are also doing some extremely ridiculous things over at Drinkstorm Studios, including our award-winning webseries, Magicland.

There are also a full 100 posts right here in the archives, and feel free to drop me a line at secondhandscience@gmail.com with comments, suggestions or wacky cold fusion ideas. Cheers!

Swarm Robotics


· Categories: Computers
What I’ve Learned:

Swarm robotics: You guys like swarms of things, right?
“Swarm robotics: You guys like swarms of things, right?”

Lots of great things come in swarms. Hornets. Locusts. One Direction fans.

Okay, so none of those things are particularly great. But robots are pretty great, and now robots come in swarms, too.

Swarm robotics hasn’t been around long, since it requires robots with three characteristics of animals that swarm together: small size, good mobility and cheap production.

And in the case of 1D fans, squealiness. But that’s not as important.

The concept behind swarm robotics is borrowed from biology, and is called “emergent behavior”. Basically, it’s the idea that a bunch of mostly-identical critters of limited intelligence can work together to do something useful that they couldn’t manage as individuals. In nature, that might be to migrate to a new nest or strip a cornfield down to its roots. Or to vote Harry Styles dreamiest Teen Beat dreamboat.

Happily, when it comes to swarm robotics, the mechanical critters — or the people programming them — are usually more sensible.

The ultimate goals of swarm robotics include things like digging mines or harvesting crops or building structures. Someday, particularly tiny robots might scurry into our bodies to clear out arteries or slice up a tumor or slap together a new liver.

Or they’ll take over the planet, build a machine city and plug all of surviving humanity into the Matrix. Which would be slightly less helpful.

For the moment, scientists are limited to current robot technology, which includes wheeled self-assembling Rubik-sized cubes and coin-sized microbots that skitter around on toothpick legs. Neither is very impressive in the singular — they’re like miniaturized Roombas that don’t bother to vacuum any more. But with a bunch of these robots (and the right programming), engineers can do some pretty interesting things.

With a few simple instructions, for instance, swarm robots have assembled to pass obstacles a single unit couldn’t navigate, and to collectively move objects much heavier than any component robot. There are even termite-inspired projects with robots that cooperatively figure out how to build simple structure designs. And recently, a team at Harvard University coaxed the largest-yet swarm of teenybots — over one thousand strong — to arrange themselves into specified shapes, using a set of extremely basic rules.

So long as one of those shapes wasn’t “Skynet”, we’re probably going to be okay. For a few more years, at least.

The real power of swarm robotics comes with numbers. As the motors and sensors and other fiddly bits get smaller and cheaper, scientists can put more of their robo-critters into action. For some jobs, it doesn’t matter if one, or even half, of them fails. Sheer numbers — and a few snippets of code — will see them through larger and larger tasks. It’s like having a nest full of insects ready to do your bidding, or a tiny team of not-especially-bright butlers waiting to serve your every whim.

So while our future could hold Matrix enslavement — or worse, an endless horde of angry Benders — for now, swarm robotics is a promising field that may help us solve some very tricky and important engineering problems.

Like getting rid of One Direction. Seriously, robotics people. How come none of you is working on that?

Actual Science:
Swarm Robotics – Introduction to swarm robotics
Guardian UK – Flight of the robobee: the rise of swarm robotics
CNN Tech – Hive minds: how swarm robots are learning from insects
Nature – Termite-inspired robots build castles
Scientific American – 1,000-robot swarm created by researchers

Image sources: RedOrbit (sea of Kilobots), Zimbio (squealy concert girls), Gunaxin (Matrix robot swarm face), Den of Geek (Bender horde)

· Write a comment
· Tags: , , , , , , ,

Sublimation


· Categories: Chemistry
What I’ve Learned:

Sublimation: it's just nature's way of cutting to the chase.
“Sublimation: It’s just nature’s way of cutting to the chase.”

The word “sublimation” can mean a number of different things. In psychology, sublimation is an emotionally-driven defense mechanism identified by Friedrich Nietzsche, and then turned by Freud into some wild-ass uncomfortable shit about your mother. Because that’s what Freud did to everything.

Sublimation can apparently also mean brainwashing someone to listen to a certain ’90s surf-ska-punk band at high volume until three in the morning, which some sadistic asshole seems to have done to our upstairs neighbor. I’d wish some sick Freudian thing on them both — but it’s the wrong way.

In scientific terms, sublimation is the process where a solid substance decides it’s not going to bother with becoming a liquid, and changes directly into a gas. Skipping the whole “melting” thing can be a real time-saver — like eating breakfast in the shower or getting dressed without underpants.

Of course, it takes a special set of circumstances for this molecular commando-ing to work. Most substances move from solid to liquid, and then liquid to gas, as the temperature rises. But at just the right combination of temperature and pressure, some compounds can be coaxed to slide straight from solid to vapor, without any of the wet stuff in between.

Which is usually not at all the way “going commando” works. So it’s all the more impressive.

Every chemical compound has something called the “triple point”, a pressure and temperature combination where it can exist in a solid, liquid and gaseous state in equilibrium. Think of it as a Zen thing — or, if you prefer, a big bowl of Neapolitan ice cream. All flavors at once, and one for all. Below this triple point, sublimation can occur. That happens at extreme conditions for most substances — but not all.

One familiar example of sublimation is often seen in science labs, haunted houses and cheesy productions of Phantom of the Opera. Namely, dry ice — which is the solid form of carbon dioxide. Instead of melting, dry ice gives off those spooky clouds of vapor that people associate with Halloween, spooky forests and black lagoons from which creatures are likely to emerge.

But even plain old water — or technically, ice — can sublimate, and at temperatures we’re familiar with. For instance, the process of freeze-drying food involves sublimation of ice crystals. So does freeze-drying’s sadder, uglier cousin, freezer burn. And glaciers and mountaintops and even comets can lose some of their ice via direct sublimation, as well.

One process that isn’t sublimation, despite the name, is (most) dye-sublimation printing. When these printers were first developed, it was thought that the dyes used literally sublimated from solid to gas — but it was later found this wasn’t the case. Still, the marketing was already in place — and you don’t say “no” to the advertising execs, so the name stuck. But in reality, only the fancier-sounding “dye sublimation heat transfer imprinting” printers are worthy of the name, and actually use sublimation.

(And just like everything in this world that needs five words to describe, they’ll cost you.)

So sublimation isn’t so strange, though it takes an odd sort of chemical shortcut to make it happen. But some days, you just don’t have time to cycle through all the phases of matter. Sublimation is just a quick way to get straight from solid to gas, without a lot of mucking about in between.

Or a lot of underpants. Like they say, sometimes science can get a little messy.

Actual Science:
Boundless – Solid to vapor process
Answers.com – Sublimation: chemistry’s phase transition
University of Toronto Scarborough – Sublimation theory
USGS – Sublimation – the water cycle

Image Sources: Explain That Stuff (phase diagram), Shower Food (just what it says), Bang 2 Write (Neapolitan scoop), The Hour (foggy Phantom)

· 1 comment
· Tags: , , , , , , , , , , ,

Telomeres


· Categories: Biology, Genetics
What I’ve Learned:

Telomeres in a nutshell: the short of it is bad, and the long of it isn't great, either.
“Telomeres in a nutshell: the short of it is bad, and the long of it isn’t great, either.”

Many things tend to get shorter as we age. Patience. Hairstyles. Time between bathroom breaks.

But something else shortens when we get older, and it’s more important than all the others. Except maybe the haircuts. Nobody likes a geriatric hippie.

This “something else” is a telomere, and it’s a squiggly bit of genetic material stuck on the end of each of our chromosomes, for protection. Sort of like those fiddly plastic things on the ends of shoelaces that stop them from fraying.

(Those are called “aglets”, by the way. That’s not science. I just thought you’d want to know.)

Telomeres play a similar role in our cells — and the cells of most everything else that isn’t a bacterium. When we’re young, the telomeres on the ends of our chromosomes are long. Each time our cells divide, the telomeres get a little shorter, until they’re very small or gone completely. Cells in that state typically don’t divide any more; they’re content to put on a shawl, find a nice rocking chair and wait for the end.

It’s like the aglets on your shoelaces got shorter every time you wore your sneakers, until they finally disintegrated, the laces unraveled and your shoes fell off. Only instead of going barefoot, your hair and skin and brain cells don’t grow back any longer. Which is somewhat more inconvenient, even if you’ve already moved to that shorter hairstyle.

The other more-than-somewhat inconvenient thing about telomere-less chromosomes is that they can lead to cancer. Without those protective bits at the end, genetic material can get chewed away, which is bad. Or chromosomes can link together and loop around, which is also bad. As in, cancer bad. Much worse than frayed shoelaces.

So longer telomeres are better, right? weeeeeell — it depends. In general, yes. Antioxidants in foods like blueberries and kidney beans and artichoke hearts help to lengthen telomeres, and that’s good.

How you get your chromosomes to eat right, I don’t know. Mine are always binging on chips and deoxyribonucleic Oreos.

The thing is, our cells also make an enzyme — called telomerase — that naturally rebuilds telomeres in certain situations. Production of this enzyme is tightly regulated; it’s not normally produced very often or in large quantities. It’s like liquid gold. Or a really good gin and tonic.

In the lab, though, scientists have shown that extending telomeres can reduce signs of aging in mice and worms. Which is great for cowards and lawyers, I suppose — but someday, it could even be applied to humans. That would be sweet.

But there’s a catch. Most of our cells don’t grow constantly. Outside of skin and hair and the insides of our intestines, many cells really shouldn’t be dividing very often. You don’t want lungs the size of life rafts, or a gall bladder you could play volleyball with. Not unless you’re opening a really weird sporting goods store.

So in those cells, if telomerase was always around, the telomeres would keep getting longer. And that might signal the cells that they should divide and divide, out of control. And what are cells dividing willy-nilly, out of control? That’s right: cancer.

So telomeres are tricky. They’re like the Price Is Right showcase game of life: you want as much as you can get, without going over. Because if you do, the consolation prize might be something way worse than Rice-A-Roni.

Actual Science:
University of Utah – Are telomeres the key to aging and cancer?
Nature / Scitable – Telomeres of human chromosomes
Scientific American blog – Aging: too much telomerase can be as bad as too little
NPR – Healthful living may lengthen telomeres and lifespans
The Scientist – Telomeres show signs of early life stress

Image Sources: The Tao of Dana (chromosome telomeres), Heavy (old hippies), Creative Homeschool (aglets), LEXpert (The Price Is Cancer)

· Write a comment
· Tags: , , , , , , , , ,

Heliosphere


· Categories: Astronomy, Physics
What I’ve Learned:

Heliosphere: It's the sun's Twinkie. We're just along for the ride.
“Heliosphere: It’s the sun’s Twinkie. We’re just along for the ride.”

There are many complicated models of what our solar system looks like. Then there’s my model: the solar system is like a giant Twinkie, with a Red Hot candy jammed in one end.

Seriously, NASA. Why make things hard, when they could be so delicious?

So here’s how the Twinkie squishes:

The Red Hot, naturally, is the sun, radiating loose particles and waves of heat in all directions. With the candy, most of the particles are artificial cinnamon flavor and FD&C red #5, and they only make it as far as the nearest taste bud.

With the sun, the particles are solar wind — a plasmafied soup of protons and electrons — and they shoot outward at roughly 1.2 million miles per hour, give or take a speeding bullet or two.

The sun is therefore much more powerful than a Red Hot candy, but considerably less appetizing. And, so far as we know, non-fat. If you’re into that sort of thing.

Back to the model. The Twinkie represents the full spread of solar material, a region called the heliosphere. This bubble of sun-spewed plasma extends roughly 120 astronomical units — or A.U., the distance from the earth to the sun. That’s a very long way. Even wasabi pea particles don’t make it out that far.

The heliosphere doesn’t extend equally in all directions, though; hence the “Twinkie-shapedness” of the model. Remember that our sun is also constantly whirling around the galaxy at breakneck speed, which stretches the plasma bubble out behind it. Imagine the Twinkie as a speeding race car, with the Red Hot near the nose.

Or a Twinkie jet plane, if you like. Any method of theoretical Twinkie locomotion you prefer is fine. This is one of the main perks of stellar science, from what I understand.

The final bit of the heliosphere model is the outer part, where the delectable Twinkie cream turns into scrumptious Twinkie cake. In space, this interface is called the termination shock, and it’s where those plasma blasts from the sun finally slow down below the speed of sound. This happens when the solar wind interacts with the interstellar medium, a haze of gas and dust and cosmic rays flowing between the stars.

As the interstellar medium slows down the solar rays, the plasma stagnates and bubbles and clumps up — much like the spongecake cradling our Twinkie. This layer is called the heliosheath, and is immediately followed by the heliopause, where the solar wind finally disappears entirely. It’s the thin brown crust that marks the final boundary between Twinkie and not-Twinkie. When you pass the heliopause, you’re no longer in the solar system.

So how many man-made objects have made this journey out of the heliosphere, to boldly go where no Twinkie has gone before? One — or possibly none. Voyager 1, launched in 1977 to explore the outer planets, has been hurtling directly away from the sun at eleven miles per second since 1980. It’s believed that in August of 2012, Voyager 1 passed through the heliopause and out of the sun’s fiery clutches.

But because we don’t precisely know what the end of the solar system looks like, researchers are still proposing and conducting tests to determine exactly how “out” Voyager 1 is. If not yet, then it’s expected to pop through the heliopause within the next year or so, followed soon by Voyager 2.

(And if my petition to NASA goes through, next by Guy Fieri.)

Breaking an object out of the heliosphere will be quite an accomplishment, once confirmed. But why anyone would run away from a cinnamon-flavored Twinkie is beyond me.

Actual Science:
Universe Today –
NASA Science – Heliosphere
Time Magazine – Humanity leaves the solar system — or maybe not
RedOrbit – Has Voyager 1 actually reached interstellar space?
The Space Reporter – Scientists using new test to finally prove that Voyager 1 left heliosphere

Image sources: PlanetFacts (heliosphere diagram), Perfectly Crazy (Twinkie racer), DeviantArt / Jonnyetc (Winston’s big Twinkie), Rock ‘n Roll Ghost and GeekDad (Voyager Fieri)

· Write a comment
· Tags: , , , , , , , , , ,

Electric Bacteria


· Categories: Biology
What I’ve Learned:

Electric bacteria: And you thought your 220V plug adapter was impressive.
“Electric bacteria: And you thought your 220V plug adapter was impressive.”

First they came to make our stoves electric, and I said nothing. Because I’m a terrible cook. I can’t even brown bagels.

Then they came to make our lawnmowers electric, and I said nothing. Because who can afford a yard these days?

Then they came to make our cars electric, and still I said nothing. Because Teslas are sexy, and only occasionally burst into flames.

But now we have electric bacteria, and there’s no one left to speak up. Presumably because they’ve been zapped by electric freaking bacteria. What’s next, nature? Chickenpox with tasers? Athlete’s foot fungus armed with bazookas? Napalm-spewing cooties?

Fear not, science fans. Unlike that Electro dude in the Spider-Man sequel, these “electric bacteria” aren’t out to fry humanity like a trillion tiny bug zappers. They’re just efficient little critters trying to cut out the middle man.

All living organisms need energy. We get ours in the form of coffee or cheese sticks or chicken cacciatore. Likewise, animals and plants ingest nutrients in various forms to get the oomph they need. Eating equals energy.

But once the grub goes down the gullet — or up the rootstalk — things get complicated. Nearly all organisms gain energy by transferring electrons from food molecules onto another molecule called ATP.

(No, not the tennis tour ATP. The only thing stored there is Roger Federer’s six thousand watches.)

ATP stands for adenosine triphosphate, possibly the most important bit of microscopic fluff in living cells, because it can hold onto electrons — and therefore energy — until they’re needed. Organisms spend a ridiculous amount of effort getting these electrons onto and off of ATP, using enzymes and cofactors and quite possibly David Blaine is involved — all because our cells can’t deal with bare electrons directly.

But some cells can.

Scientists have known for a while that certain bacterial species can gather energy from an electrical source — that is, a pool of electrons. No ATP needed; these microbes sip electrons like espresso and use them directly.

Dubbed “electric bacteria”, because they survive on raw current — rather than, say, raw currants — researchers believed they were relatively rare. But new experiments have jammed a proverbial fork into that outlet: electric bacteria aren’t rare; they’re everywhere.

Several new types of electron-munching microbes have been recently discovered. How? By jamming electrodes into the ground, turning on the juice (gently) and seeing what grows. Some bacteria in the lab can thrive on just the juice from a simple battery. No food. No water. No Chicken McCoenzymes. Just pure, unadulterated voltage. They’re like tiny little toasters, only alive and creepy and also terrible at browning bagels.

These weirdo electrical bacteria are interesting in a number of ways. Some live deep underground, slowly slurping electrons off the surrounding rocks. These may give us a hint of what primitive life on other planets might look like. They could also help us figure out the bare minimum energy cells need to survive. And they might be engineered to clean up biowaste or toxic spills, powering themselves with loose electrons as they work.

Some species even have filaments called nanowires that help regulate the electrons flowing in and out. These cells can link together, forming a bacterial bridge to transfer electrons several centimeters away. That’s not lightning shooting out of Jamie Foxx’s hands, maybe. But for teeny-ass microbes, it’s like Zeus firing thunderbolts at a bullseye on the moon.

So even if they won’t tase you, bro, don’t mess with electric bacteria. These crafty critters will shock you.

Actual Science:
New Scientist – Meet the electric life forms that live on pure energy
Astrobiology Magazine – Electric-eating bacteria
Discover – Bacteria unite to form living electric cables that stretch for centimetres
LiveScience – Electric bacteria could be used for bio-battery

Image sources: Real Simple Science (plug-in microbe), Tampa Bay Times and Flickr / Dusty_73 (cootie napalm), Silver Screen Serenade (Electro charging), CityNews Toronto (electric Blaine)

· Write a comment
· Tags: , , , , , , , , , , , ,

« Older articles
Newer articles »