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: Astronomy, Physics
What I’ve Learned:

Fast radio burst: and you thought Sex Pistols songs were short and confusing.
“Fast radio burst: and you thought Sex Pistols songs were short and confusing.”

If you’re like Fox Mulder, you believe the truth is out there.

That’s great and all, but what happens if you’re not fast enough to read it when “the truth” finally whizzes by?

That’s the sort of problem astronomers have faced since 2006, when the first “fast radio burst” (or FRB) was detected in radio telescope data recorded five years earlier. Poring over archived pulsar survey data, they found a brief spike in the signal across a range of wavelengths. It lasted less than five milliseconds, quick as a Ruby Rhod *bzzzzzz*. And then it was gone.

That may seem weird. But pulsar-hunting astronomers are used to this sort of now-you-see-it, now-you-don’t radio signal Whack-a-Mole. Pulsars are rapidly spinning neutron stars that emit radio signals, and their twirling makes the detectable signal come and go at regular intervals. Only with this particular fast radio burst, it came once… and it never came back.

Kind of like Jesus. Or Nelson Muntz’s dad.

Oh, no, wait. Nelson’s dad did come back eventually. Scratch him.

That was just the beginning of the mystery, though. The spread of the signal across wavelengths suggested that this fast radio burst had traveled across space and through interstellar gas, which can spread signal out, the way a prism does with light. Based on the spread, astronomers calculated that the signal had come from more than five billion light years away. Which meant whatever had created it must have been ginormously powerful, for the signal to make it so far through the cosmos.

That opened up a whole new can of WTFs. So far as we can tell — meaning as far as we can see with our various telescoping gadgets — there’s nothing in the region where the fast radio burst came from. No stars. No black holes. No outposts with Marvin the Martian plotting our destruction. Nada. If there’s something — or somethings — there, we’re not able to see it with our equipment. And we have no idea why it would scream at volume 11 for an instant, and then stop seemingly forever.

I mean, sure — Obi-Wan would tell you it was Alderaan. But what does he know? He doesn’t have an astrophysics degree.

The first fast radio burst was weird enough to make people skeptical. When we didn’t see another one for a few years — and when one team discovered they could make similar signals by opening a microwave door just right — astronomers wondered whether it was a technical glitch. Flying bird farts. Space voodoo. Something.

But in the past few years, ten more fast radio bursts have been detected. Now, there’s corroboration from a second radio telescope — and the last one, in 2014, was detected live as it happened. Now, scientists calculate that if we could point radio telescopes at the entire sky, full-time, we’d see hundreds — maybe even ten thousand — of these fast radio bursts per day.

That still doesn’t tell us what causes them — but there are some pretty cool theories. Each source is calculated to be no more than a few hundred kilometers wide, so these big (and quick) things are coming from some pretty celestially small packages. Some think it might be colliding black holes, or neutron stars collapsing together. Or black holes exploding, if that can even happen. Others blame them on blitzars — though why we have to bring Santa’s reindeer into this, I don’t know. We’re trying to do real science over here.

Whatever it is making fast radio bursts, astronomers are now agreed that they exist and are doggedly looking for more. Someday, with enough evidence, no doubt they’ll finally find “the truth” behind these weird astronomical aberrations.

Or they’ll find the Death Star. And I’m pretty sure Mulder wasn’t looking for that.

Image sources: PBS (fast radio burst [artist’s rendition, apparently]), QuickMeme (truthy Fox), Simpsons Wiki (Nelson and papa, haw haw!), Giant Bomb (Alderaan, we hardly knew ye)

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· Categories: Biology
What I’ve Learned:

Retrovirus: when it comes back, you don't really want to be there.
“Retrovirus: when it comes back, you don’t really want to be there.”

“Retro” is in right now.

Of course, retro is always in. In the ’70s, people pined for the ’50s. In the ’90s, they wanted the ’70s back. And now, it’s ’90s nostalgia. So is a “retrovirus” just a cold bug that dresses like Blossom and listens to Nirvana CDs?

No. For the love of everything holy in this world, it is not.

A retrovirus is instead a virus that uses a process called reverse transcription. Because retroviruses — like Blossom, but without the goofy hat — just had to be different.

Nearly every organism on the planet follows what biologists call the “central dogma”. That’s the rule that says genes coded in DNA get converted to RNA, and that RNA is then read to make proteins, which are the building blocks for cells, people, animals, plants, Joey Lawrence and the cotton inside grungy flannel shirts. Among other things.

That’s the way life works — DNA to RNA, in a process called transcription, and RNA to proteins, which is called translation. It’s a solid system, and everybody follows the same rules.

That includes most viruses, who are little more than a few scraps of DNA and maybe a protein shell to hold it all together. These viruses infect cells, get their DNA converted to RNA by the cell’s machinery, then to protein, package themselves up and look for the next cell to invade.

Nobody ever said viruses live fulfilling lives. They’re like an old retired couple with an RV, wandering aimlessly in search of early bird dinners and cheap campground fees. There’s no point, exactly, but it keeps them busy.

And in the virus’ case, it also keeps them causing flu, smallpox, herpes, warts and sometimes cancer. It’s not a perfect analogy. Old people aren’t quite as harmful as all of that. Mostly.

Retroviruses, though, refuse to play by the rules. A retrovirus doesn’t pack its DNA on road trips; it bundles up RNA instead. It also packs a special type of enzyme called reverse transcriptase. This protein flips the central dogma upside down, and can make DNA out of the retroviral RNA. This new DNA then worms itself into the host genome, where it gets converted to RNA and protein, as usual.

So retroviruses aren’t so much like the retired RV couple scoping out campsites. They’re more like a biker gang that invades your neighborhood, squats in your house and drinks from all your toilets. And not in the nice way.

Because they randomly insinuate themselves into chromosomes, retrovirus DNA can sometimes cause cancer by disrupting an important gene. And that’s on top of the diseases they cause to begin with, which include AIDS and related diseases, equine infectious anemia, avian wasting disease, encephalitis in sheep and goats, and several others.

Not all retroviral infections are harmful, though — or even active. Sometimes, a retrovirus inserts its DNA into a “silent” stretch of DNA and it’s never heard from or activated again. Like Ugly Kid Joe and Starter jackets. These “endogenous” retroviruses are so common, in fact, it’s thought their sequence makes up 5-8% of the human genome.

So when it comes to retroviruses, they’re much like “retro” trends: better left buried and forgotten than dug up, reawakened and unleashed on anyone or anything you care about. And if a retrovirus should get loose? Hide the Blossom hats and Nirvana CDs; you’re in for a rough ride.

Actual Science:
HHMI / BioInteractiveRetroviruses and viral diversity
The ScientistRepurposed retroviruses
Small Things ConsideredRetroviruses, the placenta and the genomic junk drawer
Virology BlogRetroviruses R us
QuantaKiller virus is invading koala DNA

Image sources: MedPageToday (HIV virion), StyleBlazer (big-hat Blossom), RantGizmo (RV retirees), Crudely-Drawn Filler Material (Hell’s Satans commode chugger)

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· 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 TodayRadioisotope
Carleton CollegeRadioactive decay
American Chemical SocietyProduction and distribution of radioisotopes at ORNL
NatureRadioisotopes: the medical testing crisis
WHOI / OceanusRadioisotopes 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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· Categories: Biology, Physics
What I’ve Learned:

Scanning electron microscopy - almost as exciting as... well, you know.
“Scanning electron microscopy – almost as exciting as… well, you know.”

“Scanning electron microscopy” is one of those sciency terms that looks a lot scarier than it actually is. To make sense of it, you just have to break it down, word-by-word. I start at the end and work my way backwards.

(Science is usually more fun that way. Like Harry Potter novels. Or nine-layer dips.)

So, start with “microscopy”. This is just “microscope” with a fancy-sounding “y” glommed on the end. Scientists sometimes add “y” to words to make them sound more impressive — like oncolog or rhinoplast or chemistr, for instance. But don’t be fooled; “microscopy” just means “doing stuff with a microscope”. And “microscope” means “machine that makes tiny things look bigger”.

And if you ask what “tiny things” means, we’re going to talk about your sex life. Don’t be a smartass.

Next is “electron”, which is an especially tiny thing that zips around atoms. Electrons have other properties, of course, like spin and charge and favorite How I Met Your Mother episode, but the important things right now are these: electrons are fast, unbelievably tiny — like, seriously, sextillions of the things in a grain of sand tiny — and can be shot in a tight beam like a skinnier, less murderous laser.

That just leaves “scanning”, which brings everything together. The beam of electrons is shot at the sample inside the microscope.

(Technically speaking, these electrons are said to “bombard” the target. Or in the words of one esteemed science educator:

Bombardment! Life is pain, son! Bombardment!! My post-doc lasted seventeen years! Bombardment!! Science is a cruel and less-lucrative-than-anticipated mistress! Bombardment! BOMBARDMENT!! BOMBARDMENT!!!

Yes. “Bombardment”. Thanks.)

Then the beam scans back and forth across the surface, like a printer over a piece of paper. Only instead of shooting ink (or dodgeballs), it’s electrons. These electrons excite the atoms they hit, which sends other electrons pinging off the surface. Scientists detect these “secondary” electron signals to determine the contours of whatever’s being scanned.

Sort of like a hot blind girl feeling your face to figure out what you look like, only with electrons instead of fingers. Also, most microscopic targets are more attractive than Kenneth Parcell. Which is probably good.

This technique is often used to view fixed biological samples (think “teeny critters in formaldehyde”) or the surfaces of materials like crystals or computer chips. But you can see almost anything in a scanning electron microscope, provided you can suck all the water out of it and, if needed, micro-coat it with a conductive material to provide lots of surface electrons.

(For instance, some scientists want to look at spiders. And gold is conductive and easy to layer on. So our universe now contains an actual, once-living gold-plated spider, like a villain in some arachnoid James Bond flick.

Science says, “you’re welcome“.)

By using electrons instead of light, scanning electron microscopes can magnify up to 500,000 times. So you can view bacteria and snowflakes and insect feet and grains of rice in stunning detail, down to a scale of one nanometer.

Which is a little better resolution than the monitor you’re reading this on. Yes, even if it has that “retina thingy”. Trust me.

So don’t get tripped up by the long words and fancy syllables. “Scanning electron microscopy” isn’t something frightening. After all, who’s afraid of a little bombardment?

Bombardment! Bombardment!! BOMBARDMENT!!!

Actual Science:
NanoScience InstrumentsScanning electron microscopy
How Stuff WorksHow scanning electron microscopes work
Smithsonian National Museum of Natural HistorySEM Lab gallery
WiredAbsurd creature of the week (tardigrade [w/SEM images])

Image sources: NPR (sperm and egg), Kissing Suzy Kolber (“Bombardment!!”), 30 Rock / NBC (via Netflix) (Kenneth face), Wikipedia (Goldspider)

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