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!

Tectonic Plates


· Categories: Physics
What I’ve Learned:

Tectonic plates: Putting the 'rift' in 'continental drift'.
“Tectonic plates: Putting the ‘rift’ in ‘continental drift’.”

The Earth — or the bits of it we live on, anyway — is like the Kardashians.

(A chilling premise, I know. Feel free to roll around in the fetal position for a bit while that sinks in. I’ll wait — and then I’ll explain.)

The Earth’s surface is made up of independent sheets of planetary crust called “tectonic plates”. Parts of these plates — and some entire plates — lie under the ocean, but there are some rocky bits that manage to peek out above the surface of the waves. Scientists call these bits “land”.

(So does everyone else, obviously. Scientists just like to feel official about things.)

It’s these stretches of land, divided into continents, that share some traits with the Kardashians. So Europe is, I don’t know, Khloe. And South America can be Kim, with her high-Andean-altitude ass. Maybe Kourtney is Greenland, and…

Well, those are all the Kardashians I know, actually. Is Krusty one? Or Katzenjammer? Tito? Like all things Kardashian, it really isn’t important. Assign your land masses however you like.

The key things to know is that there are seven or eight major tectonic plates, depending on whom you ask, and another few dozen minor ones. Hangers-on, if you will. Distant cousins. Papparazzi.

(That’s one, right? I totally remember Papparazzi Kardashian being pulled over by cops for something. It was on all the channels starting with T-M, probably.)

Three hundred million years ago, all the tectonic plates containing land were huddled together like a big happy family in one supercontinent called Pangaea. They stayed together for about one hundred million years — so, slightly more seasons than the Kardashians managed — before finally breaking apart.

(And what’s more, it wasn’t the first time the whole family had come together. Geologists think there were at least four supercontinents mushing together all the land masses throughout prehistory, going all the way back to two billion years ago. It seems reunion specials and reboots have always been in vogue.)

It wasn’t constant in-fighting that drove the tectonic plates in Pangaea apart. Rather, the continents drifted due to geologic, tidal and gravitational forces tugging them into the configuration we know today. But the interactions between those plates as they moved along would be familiar to any Kardashian or reality TV fan. Specifically, there was:

Converging – where two tectonic plates came at each other (bro), one was pushed underneath the other in a sort of intercontinental cat fight. This can create ridges and even mountain ranges (like the Andes), where the “winning” plate is lifted up over the other. In plate tectonics, it’s usually the denser plate that’s thrust down, in a process called subduction. (In reality TV, sadly, the denser you are, the more camera time you’ll probably get.)

Diverging – where two plates drifted away from each other, with one never calling or writing or joining up for mani-pedi spa days any more, a rift would form between them. When it happens under the ocean, new material from under the Earth’s crust will rise and fill in; this is how we get new sea floor. When it happens in the entertainment world, some new bunch of idiots will rush in to plug the void; this is how we get Jersey Shore.

Transforming – sometimes two plates constantly rub and grind against each other — or against Lamar Odom, possibly. This causes friction and instability, and can lead to something called “transform faults” (like the one in San Andreas) where earthquakes frequently arise from all the tectonic jostling. Which is almost certainly less catastrophic than the product of all the Kardashian rubbing and grinding, which is usually more Kardashians.

So that’s the story of tectonic plates. Perhaps not the geologic migration process we wanted, but at this point probably the geologic migration process we deserve. Downton Abbey, it ain’t.

Actual Science:
Bucknell University – Plate tectonics
National Geographic – Plate tectonics
Nature – Earth science: how plate tectonics clicked
PhysicsWorld – Geophysicists blast their way to the bottom of tectonic plates
Scientific American – What happens to Google Maps when tectonic plates move?

Image sources: Ella-Rose’s Learning Portfolio (tectonic plates), Too Funny Chicks (tug of Kardashians), HefferBrew (rubbing Lamar), Kontrol Girl (template for Pangaean posers)

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Radioisotopes


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

Radioisotopes: When they have a meltdown, you might, too.
“Radioisotopes: When they have a meltdown, you might, too.”

Chemical elements are exactly like people: there are almost two hundred of them, and only a handful you’d want to invite to a dinner party.

(Okay, it’s possible there are more than two hundred people. But the second part still stands.)

The other way elements are like people is that they both have baggage. With people, it’s a messy divorce, or a predilection for making their pets wear sweaters. Or being an outlier on the Bell curve charting “frequency of parental hugs”.

With elements, it’s neutrons. Nothing else. Just neutrons, little uncharged subatomic bits of schmutz. You would think that would take all the drama out of having baggage.

You would be wrong. It’s like the Real Housewives of the Periodic Table down there. Here’s why:

You can dump extra neutrons onto an atom, no matter how small. Take hydrogen, for example — the runtiest little element of all. It’s got just one proton — the other bit of atomic schmutz that has a positive charge, to offset the negative electron circling the nucleus — and no neutrons at all. Hydrogen is simple that way, like a monk or a wise old hermit or that kid who used to shine shoes on Parks and Recreation, before he got married and buff and went into outer space with that tree and the rodent and the rest of them.

You can pile a neutron onto a hydrogen atom, and it’s mostly fine. This atom is called an isotope, because it’s got more (or less) than the usual number of neutrons — and it’s called deuterium, because that’s what hydrogen atoms with one neutron like to be called.

(I don’t know what sort of nicknames its friends give it. “Deutie” seems fraught with issues. “Deut”, maybe? “Terie”? No idea.)

But deuterium, laden with baggage though it is, is very stable. Makes good decisions. Keeps a steady job. Probably doesn’t even have a therapist — unless it lives in L.A., because pretty much everybody has a therapist there, but still. Deuterium isotopes are chill.

Until you feed them another neutron.

Then those isotopes become tritium, which is a radioisotope. And radioisotopes are atoms where the baggage has gotten to be too much, and it gets unstable. These are the atoms with the crazy eyes, and — like most anyone with too much baggage — they’ll eventually dump it out on those nearby. Explosively.

For radioisotopes, this means radioactive decay — a release of stored energy which brings the atom into a more stable state. Tritium, for instance, decays into an atom of helium-3 (two protons, one neutron), which is completely stable, and fine to invite over for parties or to babysit the kids. But the energy and particles released by decaying radioisotopes can be bad news — or extremely useful, depending on the atom.

Some forms of radioactivity can cause radiation poisoning, cancer or fish with an uncomfortable number of eyes. The rate at which radioisotopes blow their atomic stacks is measured as a half-life — that is, the amount of time it takes for half the atoms in a sample to go completely batshit and decay. Knowing this half-life (and the type of decay — alpha, beta, gamma or other) can come in handy where just the right amount of radioactivity is helpful — like americium-241 used in smoke detectors, or gadolinium-153 used for certain kinds of X-ray tests and osteoporosis screens.

But the most temperamental and energetic radioisotopes — the Kardashians of the atomic world — can cause problems for centuries or longer. Carbon-14 and strontium-90 from nuclear bomb tests, for instance, with a half-life of nearly six thousand years, or nuclear reactor output like cesium-137 and iodine-131 (which can also be used as a cancer treatment, under carefully controlled conditions).

So the next time you decide to dump baggage on someone — or unload some of your own on innocent bystanders — take a moment to think of the radioisotopes. Some of them are just as unstable as you. Only they wig out and break down because of science, and not a tragic hug imbalance. Neat.

Actual Science:
Universe Today – Radioisotope
Carleton College – Radioactive decay
American Chemical Society – Production and distribution of radioisotopes at ORNL
Nature – Radioisotopes: the medical testing crisis
WHOI / Oceanus – Radioisotopes in the ocean

Image sources: NOAA Ocean Explorer (radioisotope decay), Organizational Excellence (Bell curve for hugs), Splitsider (stoked Andy Dwyer), KnowYourMeme (crazy-eye girl), Into the Deep (Simpson’s several-eyed fishies)

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Ionizing Radiation


· Categories: Physics
What I’ve Learned:

Ionizing radiation: Hide your electrons, 'cause they ionizin' everybody out here.
“Ionizing radiation: Hide your electrons, ’cause they ionizin’ everybody out here.”

Science is hard. Even when something in science sounds straightforward, it usually isn’t.

And mostly it doesn’t sound straightforward at all. Even the names of scientific concepts are hard. Like “endoplasmic reticulum”. That’s just a jumble of Scrabble tiles, no matter how you break it down. Or “Schwarzschild radius”, which sounds like part of an equation you’d use to calculate how much cream cheese you’ll need for that bag of bagels you just bought.

But occasionally, science throws us a nomenclatural bone. Like “ionizing radiation”. Those words actually make sense; you can suss from the name that this is “radiation that ionizes”. Simple, right?

Weeeeeeell…

Start with ionization. An ion is an atom or molecule that has either more electrons or less electrons than you’d expect, given its properties like size and composition and pants size. Because electrons have a negative electric charge, that means this electron-lopsided thing also has a charge — positive if it’s missing electrons, negative if it’s hoarding them like some A&E channel reality show weirdo — and it’s called an ion.

With ionizing radiation — more on the “radiation” bit in a sec — electrons are not hoarded. They’re knocked off at (or near) the speed of light, chucked away like a Hefty bag on trash day. Or a kid out of Mom’s basement after graduation. Or John Travolta out of Hollywood after Battlefield Earth.

One way to think of the effects of ionizing radiation is that the resulting ion is still intact, more or less, but now it’s missing something. If you see a car without hubcaps or a fender lashed on with bungie cords, it’s still a “vehicle”, technically. It’s just a shitbox ion. A house with peeling paint and a hole in the roof remains a “dwelling” — but it’s a crapshack ion. Something’s missing. A little off. Busted.

So if you don’t want your precious atoms and molecules ionized — and you don’t — what sorts of radiation do you need to watch out for? Well, radioactive decay, for one. Whether it’s alpha particles, beta particles or high-energy delta-delta-delta-can-i-help-ya-help-ya-help-ya particles, they’re all ionizing radiation. Ditto for gamma rays, cosmic rays, X rays, ultraviolet rays and seemingly every other ray besides Rachel.

(Okay, that’s not precisely true. From an ionizing perspective, visible light rays, microwaves, infrared and even some ultraviolet rays are safe.

Also, Rachel Ray will probably eat you with her enormous mouth. Which isn’t “ionizing”, exactly. But it can’t be good.)

That’s what ionizing radiation is — but what does it do? Several bad things, and a couple of good. On the negative side, ionizing radiation can break chemical bonds, create free radicals and turn substances radioactive, among other things. Those effects are pretty bad for materials like metals and polymers and semiconductors, and really terrible for materials like you. In people and animals, high ionizing radiation doses cause radiation burns, DNA damage, chronic sickness, cancer and death. It’s no party.

On the other hand, ionizing radiation can be put to good use. The effects are critical for X-ray imaging, smoke detectors, some food sterilization, radiochemistry, medical tracers and lots of other applications. The key is to be careful, and balance dangerous exposures with practical use.

Also, don’t let Rachel Ray near any of the stuff. I don’t know what a dose of radioactivity would do to her — but I’ve seen Spiderman, and I do not want to find out.

Actual Science:
World Health Organization – What is ionizing radiation?
Environmental Protection Agency – Ionizing and non-ionizing radiation
Physics Central – Ionizing radiation and humans – the basics
Astrobiology Web – Effects at Earth’s surface following astrophysical ionizing radiation events
OnCancer / MSKCC – Scan safety: a radiation reality check

Image sources: Mammography blog (ionizing radiation), CinemaBlend (Battlefield John), Hulu (“Delta Delta Delta!”), SoGood (gaping Ray)

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Trans-Neptunian Objects


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

Trans-Neptunian objects: Stuck where the sun don't shine (very much).
“Trans-Neptunian objects: Stuck where the sun don’t shine (very much).”

In the beginning, there was the Earth.

Meaning, that’s the first solar system object humans knew about, mostly because we kept tripping and falling face-first onto it. Early humans weren’t particularly coordinated.

The sun was also pretty hard to miss, what with the light and heat and occasional scary eclipses. By the 2nd century B.C., eagle-eyed up-gazers had also spotted Mercury, Venus, Mars, Jupiter and Saturn. Not bad for people who didn’t have a LensCrafters at the local mall, probably.

It took a couple thousand years — and eyeglasses, binoculars and telescopes — to find the remaining (current) planets, Uranus (1781) and Neptune (1846). And then we had a problem. Based on calculations of the outer planets’ masses and shapes and favorite Hostess snack cakes, it appeared they were being influenced by some unseen astronomical force — other objects, further out, pulling the strings on Neptune’s orbit. (And pre-packaged dessert preference, apparently. Team Ho-Hos forever.)

So scientists went looking for these mystery bits of rock, called “trans-Neptunian objects”, because they spent (most of) their time chilling outside the orbit of Neptune, thirty times further from the sun as Earth. In 1930, they found the first trans-Neptunian object, and called it Pluto.

On the good side, Pluto was pretty much where astronomers thought it would be. On the bad, it wasn’t large enough to explain the discrepancy in Neptune’s behavior. Better measurements of Neptune determined its orbit actually made perfect sense, so they chalked it up to dumb luck, Pluto became the ninth planet, and nobody looked much for more trans-Neptunian objects for a while.

But Pluto seemed awfully lonely, way out there in a dusty corner of the solar system. So when a second trans-Neptunian object was spotted in 1992, the search was on again. Since then — because even our telescopes have LensCrafters now, probably — more than 1,500 trans-Neptunian objects have been found. So many, in fact, they get grouped into weird classifications like “twotinos” and “cubewanos” and “plutinos”.

(It sounds like the lineup for a Saturday night at the Mos Eisley cantina. But that’s really what they call them.)

All this family reunionizing was great for Pluto, presumably — until it wasn’t. In 2005, a trans-Neptunian object called Eris was found. It looked like Pluto. It had a moon, like Pluto. And it was bigger than Pluto — but no one was quite convinced it should be called a planet. So astronomers got together in 2006 and worked out criteria that said no, sorry, Eris is not technically a planet.

And oh, by the way, if you use the same criteria, neither is Pluto. Ouch. Finding Eris was like going on a date with someone who you don’t like very much, and instead of making you miss your previous relationship, you just realize you had bad taste in dating all along. Maybe you should try OKComet instead.

But there’s more. As astronomers discover even further-out hunks of rock — called extreme trans-Neptunian objects, because they drink Red Bull and get tattoos and stay out past curfew, I assume — an old problem reemerges: they don’t look quite right. In fact, a recent paper studying the orbits of some of these way-out objects says that apparently they are being influenced by something (or somethings), legitimately planet-sized and dark and mysterious even further out. So far, scientists haven’t seen them — or agree they exist — but some are now squinting their telescopes outward, just in case.

Here’s hoping they have a good LensCrafters nearby.

Actual Science:
Space Answers – What are trans-Neptunian objects?
National Geographic – Pluto gets 14 new neighbors
Universe Today – The Dark Energy Survey begins to reveal previously unknown trans-Neptunian objects
Space.com – Mysterious Planet X may really lurk undiscovered in our solar system
The Quantum Tunnel – The big bang theory of trans-Neptunian objects

Image sources: NASA/JPL-Caltech (Sedna, the sexy TNO), Simon.com and FreePik (‘Scopes heart LC), Princess Burlap (“I said, Team Ho-Hos!”), Electronic Cerebrectomy (Mos Eisley cantina band), FB-Troublemakers (sad Pluto)

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Special Relativity


· Categories: Physics
What I’ve Learned:

Special relativity: out with the aether, in with the aother.
“Special relativity: out with the aether, in with the aother.”

On the heels of the holiday season, you may have recently witnessed instances of “special relativity”. Grandma’s secret-recipe fruitcake pucks. Your uncle’s uncomfortably falsetto rendition of “O Holy Night”. Cousin Lem’s drunken faceplant into a bowl of Christmas bisque.

Happily, that’s not the only sort of special relativity. One hundred and ten years ago, Albert Einstein (with a little help from his friends) developed a theory that explained the behavior of things that travel near the speed of light. Like New York City taxis, or Usain Bolt. Or, you know, light.

This theory was needed because by the late 1800s, scientists had figured out that their plain old regular-speed relativity — based on work by Galileo and Newton, among others — wasn’t always getting the job done. This old school theory, called Newtonian relativity or Galilean invariance, because see the previous sentence, sport, said there is an “absolute space” and an “absolute time”, in which everything happens. And by that time, it also included an “absolute reference frame”, a universally unique point of view from which electromagnetic wave properties like the speed of light could be accurately measured.

Problem was, experiments suggested that if that uniquely-accurate reference frame (known as the “aether”) existed, all measurements made in labs were consistently in agreement with it. In other words, all those labs were stationary with respect to this spatial frame of reference. Which would be super, if we didn’t know that the Earth is constantly swooping around the sun (and the sun around the Milky Way, and the Milky Way hurtling through the universe), so it’s not really “stationary” compared to anything but itself.

Einstein dropped this “aether” concept down the nearest aelevator shaft, and that was just the beginning. He also decided that space and time were two great tastes that taste greater together, and mushed them together into something called “spacetime”. And he said no matter how fast you’re going (or not), the speed of light will always look the same. That let a whole bunch of crazy — but later experimentally verified — cats out of the physics bag. For instance:

Under special relativity, two people moving at different speeds may watch the same event happen, but observe it occurring at different times. And not just because one of them has TiVo, either.

If you watch two clocks — one moving and one sitting still — the moving clock appear to go slower. (And if it’s moving while you’re sitting in your office at ten minutes til five on a Friday afternoon, it’ll appear to go reeeeeeeeally slow.)

Mass and energy are equivalent, as given in Einstein’s famous special relativistic equation, E = mc2. This is obvious to anyone who’s eaten a four-ounce chocolate eclair and felt the kajillion-calorie jolt to their metabolism as the mass is converted to energy… and then seen six pounds of flab appear on their ass as it converts back to mass.

(I don’t know why it gets bigger in the conversion. What am I, some wild-haired German genius math guy?)

Basically, Einstein’s special relativity theory made some predictions crazier than drunk old Cousin Lem on an eggnog bender, but they turned out to be true where Newtonian relativity did not. Either theory will get you through the day for normal stuff — but if you’re zooming around near the speed of light, then you’d damned well better listen to Einstein.

He may not be your relative. But believe me — he’s special.

Actual Science:
LiveScience – What is relativity?
American Museum of Natural History – Special relativity
HowStuffWorks – How special relativity works
io9 – Get pelted every day with particles that confirm special relativity
The Physics Classroom – Relativistic length contraction

Image sources: QuickMeme (it’s all relativity), Telegraph (UK) (blurry Bolt), Food Navigator (food faceplant), London Evening Standard (an eclair and present danger)

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