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!

· Categories: Physics
What I’ve Learned:

The Doppler Effect: yet another reason to run from screaming children.
“The Doppler Effect: yet another reason to run from screaming children.”

Most science happens in a laboratory or a particle accelerathingy or inside the brain of some bushy-eyebrowed theory geek. The applications don’t make it far into the real world. Like, why do we never see nonhomologous recombination in the newspapers? Or a cartoon starring Schrodinger’s cat?

Which would presumably be a fan of lasagna, but not so much of Mondays. Just based on previous observations of animated feline behavior.

But once in a while, we’re thrown a bone — a science bone — and we get to see what the eggheads are talking about in their fancy journals and proceedings. Like the Doppler effect, which we can observe on a regular basis — or daily, depending on your neighborhood — and also hear about on the local six o’clock news. That’s more public exposure than Jeremy Piven gets.

Although, to be fair: it’s Jeremy Piven. So.

Anyway, the Doppler effect has to do with waves, and the way they change in frequency relative to motion. Sound waves, for instance. Imagine a toddler in a mall throwing a tantrum, and screaming “MOMMY!” at one-second intervals. As toddlers do.

Now, if you’re moving toward the child — maybe you’re “MOMMY”, and you have the binky that will end this meltdown — the sound of those one-per-second screams will reach your ears faster. If you could run fast enough (and please do; we’re trying to shop here, ma’am) in the direction of the kid, you’d notice the frequency of those screams getting closer together. The child’s still shrieking them once a second, but you’re plowing toward them, so you get to the next one faster than, say, some guy just sitting in the food court with breadsticks shoved in his ears.

That change in frequency is the Doppler effect, and it’s a result of relative movement between the source and the receiver of the waves in question. So if you’re sitting still — because “Mommy’s tired”, obviously — but the squirt comes screaming toward you, the effect will be the same. On your ears, anyway. If not necessarily your Xanax prescription.

The Doppler effect works in the receding direction, too. If your relative motion is away from a wave source, the frequency will decrease as you move further away. With sound waves, pitch varies with frequency, which is why sirens — or toddlers — coming toward you sound high-pitched as they approach, then normal as they pass and lower-pitched as they speed past.

But autotuning ambulance noises and screaming tots isn’t the only trick up the Doppler effect’s sleeve. Light is a wave, too — depending on the time of day and which theoretical physicist you’re talking to — and astronomers can use observations of starlight to determine whether those stars are moving toward us or away from us. But rather than changing pitch, light undergoing a Doppler effect shifts color instead. So light sources coming at us skew toward blue wavelengths, or are “blueshifted”, while light from stars streaking away shows a “redshift”.

And what about the Doppler effect horning in on the local news? Well, radar is another type of electromagnetic wave, and works just the same as light and sound. That “Doppler radar” the weatherman gets so excited about determines the speed and direction that storms are moving by measuring the Doppler effect on radar waves bounced around the atmosphere.

There are plenty more examples, but you get the idea. Also, that kid’s not going to cram his own binky in his mouth, apparently, so maybe you could take care of that now, mommy. Mommy. MOMMY!

Image sources: CK-12 (it’s the Doppler coppers!), CinemaBlend (pouty Piven), Ramblin’ Mama (kid, keening), Twilight Language (randy radar reading)

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

Jeans instability: The fancy-pants stuff behind every star.
“Jeans instability: The fancy-pants stuff behind every star.”

Science is hard. Most of it is obviously complicated and full of tongue-twisty words that exist only so some eggbrain jerkass can school you at Words with Friends. But it’s sneaky, too. Whenever some small bit of science seems simple and straightforward, there’s always something way harder and full of Greek-letter math lurking underneath. That’s how science gets you.

Take Jeans instability, for example.

Everything physicists tell you up front about Jeans instability makes perfect sense. You’ve got this lumpy stuff called Jeans mass, and a size called a Jeans radius. If the Jeans mass exerts too much pressure for a given Jeans radius, the system flies apart and the mass spreads all over.

We’ve all been there. Like an hour after after Thanksgiving dinner.

On the other hand, if the Jeans mass has too little pressure, then Jeans instability occurs and the system collapses in on itself.

Presumably in a little pile around your ankles. I can’t say I’ve personally had experience with this phenomenon. It sounds like one of those tragic Euro supermodel problems. Oh, those poor twiggy bitches.

All of this is well and good, until the physicists then tell you that none of this has anything to do with distressed Calvin Kleins, Levis 501s or high-waist super skinny Jordache denim jeggings — and is that last one actually a thing? Merciful Darwin help us all.

To physicists — who mostly wear plain, practical polyester pants, it turns out — Jeans instability is a whole other thing entirely. It’s a phenomenon named after British physicist Sir James Jeans — personal legwear preferences unspecified — and describes the conditions under which interstellar gas clouds collapse to form stars.

On the bright side, most of the above reasoning still holds true. If the outward pressure of the gas in a cloud of a given size is too great — because the gas is especially hot, for instance — then the pressure will overcome gravitational force, and gas will spill out everywhere.

Like I said, usually an hour after Thanksgiving dinner. That happened to me twelve years ago, and Grandma still won’t invite me back for holidays.

But if the gas is sufficiently cool, or the mass of the cloud unusually high for the space it’s in, then gravity wins out and the gas will collapse in on itself, eventually forming a discrete object called a protostar, and later a star. It’s the Jeans instability that predicts under what conditions this collapse will begin to occur.

(Presumably, it includes declining seconds on pumpkin pie. Again, I wouldn’t know. That would require a stronger cloud of gas than I.)

That’s the good news, in terms of simplicity. The bad news is, the original equation for Jeans instability has been found by later researchers to not be completely accurate for real-world predictions. Which might explain why people try to fit into pants two sizes too small. Also, that equation for Jeans instability looks like this:

And to get the Jeans mass, you apparently solve this gibberish:

And the Jeans radius — more often called Jeans length — comes out the back end of this beast here:

I don’t know what any of that means. I have trouble enough figuring out the right inseam to put in the form on the Wrangler website. What if the gas cloud is wearing a belt? Is there more instability if you acid wash first? And how do I convert the units for the gravitational constant into boot-cut?

I’m telling you. Science is hard.

Image sources: Thinking Sci-Fi (baby protostar), Tenderfooting (gobbledy-Scrabbledy-gook), Denimology (serious jeans instability), LukeHamby (jeans + ankles = jankles), Wikipedia (scary equations)

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· Categories: Physics
What I’ve Learned:

WIMPs: Massive, dark and WIMPy is no way to go through life, son.
“WIMPs: Massive, dark and WIMPy is no way to go through life, son.”

There are lab geeks, biology nerds and chemistry dorks. But did you know there are also particle physics WIMPs? And that they’re dark and mysterious, and not especially wimpy at all?

(Also, they’re not particle physicists. Most of them couldn’t punch their way out of a wet bag full of hadrons.

I’m just saying. Banging atoms together and scribbling down equations all day doesn’t exactly qualify as “cross-training”.)

WIMPs are actually elemental particles — specifically, Weakly Interacting Massive Particles. Or rather, they would be, if they weren’t hypothetical, which at the moment is what they actually are. Or aren’t. Or might be. Theoretical physics is sort of confusing to talk about.

Let’s try this: if they exist, WIMPs might be the particles that make up the “dark matter” astrophysicists are always going on about. In fact, that’s basically how the idea of WIMPs came about.

Basically, “dark” matter is stuff out there in the universe that — unlike stars, planets, space junk and giant Pharaoh Bender statues — can’t be seen with a telescope. That’s because dark matter doesn’t interact via electromagnetic means, so observations using light, infrared, X-rays, radio waves and basically all the other ways we probe the universe, are off the table. The dark matter — or something — must be there, because it exerts gravitational effects on the things we can see. And there’s a hell of a lot of it — more than four times the amount of “un-dark” matter in the universe.

(This may seem like esoteric cosmological knowledge, but it really comes in handy for making yourself feel better when you’ve cheated on a diet. Just remember: for every cupcake you eat, there’s four more cupcakes’ worth of dark matter out there somewhere that you haven’t eaten. So that’s something.)

According to smart space people — that’s smart people who study space, not smart people from space, obviously — one way of working out what dark matter is made from involves a relatively heavy particle that interacts only via gravity and the weak nuclear force. (Hence the “W” in WIMP, for weak; see what they did there.)

At the same time, one flavor of a popular particle physics theory called “supersymmetry” predicts elemental particles with the very same properties. This confluence of “two great tastes that taste great together”, theoretically speaking, has been dubbed the “WIMP miracle” in scientific circles.

(Thus replacing the previous scientific definition of “wimp miracle”, which was “that time Anthony Michael Hall and the other goober created Kelly LeBrock in their bedroom”.)

Miracles aside, the big problems with WIMPs is that nobody has ever seen one. They wouldn’t be easy to find, naturally, but theories suggest that they might be produced in places like galactic centers, certain particle accelerator collisions and possibly the sun. Mostly, physicists have to search for detectable breakdown products of rare events that suggest WIMPs were involved, and hope they see enough evidence to distinguish from other possible sources. So far, they haven’t.

As the search for WIMPs continues, other theories attempting to explain dark matter have emerged. These include strong interacting massive particles, massive compact halo objects (including black holes) and robust associations of massive baryonic objects. All of which have corresponding acronyms, of course.

So particle physics has ranged from WIMPs to SIMPs to MACHOs to RAMBOs. In other words, it’s run through the Weird Science plot from the miracle girl’s perspective. That’s nice, but it hasn’t solved the mystery of dark matter yet. Somebody call me when the Chet hits the fan.

Image sources: APS Physics (WIMP search plot), Normal Level of Crazy (cupcake stuffing), Dino Bone (science, weirdly), Life and Style (steaming pile of Chet)

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· Categories: Physics
What I’ve Learned:

Faraday cage: If you can't keep your wavelength in your pants, keep it in your Faraday.
“Faraday cage: If you can’t keep your wavelength in your pants, keep it in your Faraday.”

They say too much of anything can be bad. Sunshine. Children. Tribbles. Jalapeno chili dogs, probably, though I frankly can’t imagine how.

Too much electromagnetic radiation can be a problem, too. Whether in the form of a devastating lightning strike, a searing high-voltage current or dangerously delicious microwaves, some sorts of electricity you don’t want zapping through you. Because it might sting. Or leave a hole.

When you need to avoid catastrophically harmful electric charges, you have a couple of options. You could train really hard to get fast enough to outrun electromagnetic waves. But they move at the speed of light — since light is an electromagnetic wave, after all — so that’s probably slightly impossible. You could swap yourself out with someone who doesn’t mind going through life extra-crispy. Or you could climb into a Faraday cage.

Let’s walk through that last option. It seems the easiest. Also the least murdery.

To climb into a Faraday cage, you’ll first need to build a Faraday cage. Or buy one; maybe somebody on Etsy sells them. What you’re looking for is an enclosure made of some material that conducts material, like metal. The cage can be solid or made of mesh, so long as the holes in the mesh are smaller than the wavelengths of radiation you’re trying to keep out. Make your mesh-holes too big, and you’ll still get cooked; you’ll just get cooked in an interesting pattern. Like a steak with crosshatch grill marks, or a sunbather with “friends” who drew on his back in Coppertone.

Faraday cages work by distributing electrical charge around the structure. Since the whole cage conducts the charge, a constant voltage is created all around. Electrons in the conducting material crowd to one side or the other, effectively cancelling the electrical field zapped in. Anything (or anyone) inside the cage is protected, as there’s no voltage differential in there to generate electrical current.

The contraption is named for British physicist Michael Faraday, who conducted experiments back in the mid-1800s to prove that cages work for protection. We’re not sure if he started with cages, but since you don’t see any Faraday aquariums or Faraday litter boxes around, it’s safe to say that cages probably worked the best.

There are lots of scientific uses for Faraday cages; any time it’s useful to block an electromagnetic signal of some kind, the cage comes to the rescue. They’re used to protect computer equipment — and also car and airplane passengers — from lightning strikes and electric surges, to eliminate electromagnetic interference from sensitive tests (including MRI readouts) and to screen electrical cables from outside signals.

In less-than-scientific applications, Faraday cages have been used to keep people from electronically spying on pope-picking sessions at the Vatican, by shoplifters to block RFID signals on swiped merchandise and by thousands of doomsday preppers, paranoids and conspiracy wingdoodles to line their wallets, bomb shelters and tinfoil hats, so “the gummint” can’t track them, read their thoughts or steal their secret varmint gumbo recipes.

(Or maybe it’s the aliens they protect against. Or the Illuminati. Hell, it could be the chili dogs. Whatever.)

Also, since Faraday cages can dissipate signals that originate inside the box as well as outside, they’re very useful for shielding potentially harmful electromagnetic energy sources. Like an electrical power plant or microwave ovens or Jamie Foxx in that Spider-Man sequel, maybe.

(Maybe a Faraday cage wouldn’t hold Electro. But electrical line workers do wear “Faraday suits”, which are modified cages that keep them from getting shocks while working on high-voltage lines.

So if Foxx’s character had just worn the proper safety equipment, nobody would’ve had to sit through that hodgepodge of nonsense for two hours.)

Anyway, Faraday cages are pretty simple, really useful and great for keeping nasty electromagnetic waves away from tender vulnerable computers, equipment and humans. And those gumbo recipes. I’m sure those were exactly what Michael Faraday had in mind.

Image sources: Life on the Blue Highways (Faraday cage demo), Drop the Beat on It (sucky sucky sunburn), The Telecom Blog (tinfoil Bart), Coop on the Scoop (Electro, crackling)

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

Orbital decay: Life's a drag, and then you burn. Or worse.
“Orbital decay: Life’s a drag, and then you burn. Or worse.”

Gravity is scary. Like, horror movie monster scary.

Think about it; gravity is relentless. Just when you think you’ve lost it, there’s gravity behind you, shaking its chainsaw or hockey mask or Lee Press-On fingerblades at you. And it’s sneaky; even if you make it to the abandoned cabin where the lights don’t work and the caretaker killed a busload of nuns exactly fifty years ago tonight, gravity will be inside, lurking in the shadows. You can hide under the covers, but gravity is already under the bed.

Face it — you’ll never escape gravity. If it weren’t the earth yanking you down, it’d be the sun or Jupiter or a rogue black hole. The pull is inevitable, like iron toward a magnet. Or Paula Deen toward butter.

But you can reach a truce with gravity — temporarily. With just the right velocity, your momentum will exactly counteract the force of gravity toward, say, the planet below. You don’t fly away, and gravity doesn’t splat you onto Earth; instead, you achieve a “stable orbit” and circle around and around.

But like Jenga towers and Facebook relationships, things aren’t really as “stable” as they seem. The truce falls apart over time, leading to something called orbital decay. Gravity wins, and the orbiter takes a nose-dive toward the orbitee.

When orbital decay happens to artificial satellites — like space station Mir or the Hubble telescope — one of two things comes next: some space scientist will push the satellite further up to counteract gravity, or it will plummet toward Earth, incinerating (we hope) in the atmosphere on the way down.

Other bodies experience orbital decay, too. Moons, for instance, can get sucked into their planets and destroyed; no Death Star laser beam required. Stars collide, and really wish they hadn’t. Even galaxies and black holes, circling for millions of years, can eventually experience orbital decay and smush each other stupid.

So what causes orbital decay? And why can’t we have nice things, cosmically speaking?

A few reasons. The balance between “orbiting” and “plunging toward destruction” is precarious; the slightest nudge can throw it off. Near a planet like Earth, tiny molecules of gas making up the sorry excuse for a high-altitude atmosphere will do it.

Satellites plow through these specks of gas, no problem — but they do get slowed down, infinitesimally. Those orbital brake-taps add up, and eventually cause a slight drop in altitude — down to where the atmosphere’s thicker, which leads to more slowing, and further dropping, and so on. It’s a vicious spiral, ending with a satellite faceplant from ten thousand miles high.

But there’s more than one way to decay an orbit. A lumpy orbitee, for instance — if the mass of a planet or star isn’t distributed consistently, orbiting bodies will get whanged around by the irregularities until they finally cut loose. And if the orbiter is large enough, it can bring this fate on itself by creating tidal forces on the larger body that squeeze it out of shape.

(This is why most satellites take spin classes, just to stay trim.)

Really huge orbiters have another problem: gravitational radiation. When supermassive objects like neutron stars orbit each other, Einstein’s general relativity theory predicts that gravitational energy waves streaming away from them should cause orbital decay over time. In recent years, astronomers have found binary stellar systems that appear to behave just the way predicted by the theory, which some didn’t expect. Even dead for sixty years, Einstein’s still smarter than a lot of physicists. But even he couldn’t escape gravity.

And neither can you; even if you negotiate with it, gravity has friends who will sneak up and kneecap you, just so gravity can finish you off. It’s like Freddy Krueger, backed by gremlins. Or Chucky with a nest of facehugging aliens. Or Jason Voorhees with a horde of zombie henchmen. And that’ll put the “decay” in your “orbital decay”, let me tell you.

Image sources: A-Level Physics Tutor (orbital decay), Houston Press (Paula Deen, butterface), Me and My Bread Knife (Facebook relationships), PsychoBabyOnline (Jason with machete, no zombies)

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