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:

Very Large Array: My, what a big telescoping instrument you have!
“Very Large Array: My, what a big telescoping instrument you have!”

Reasonable men and women can disagree — and lord, they often do — about what qualifies as “very large”. Reasonable astronomers, however, agree that the Karl G. Jansky Very Large Array of radiotelescopes in the plains of New Mexico is indeed “very large”.

It’s right there in the name. No debate or overcompensation or embarrassing pumping equipment necessary.

To be fair, 27 x 25 sounds pretty darned big, and the Very Large Array backs those numbers up: it’s comprised of 27 separate telescopes, each with a 25-meter diameter dish. The antennae are arranged in a Y-shaped formation, with a total collection area covering more than thirteen square miles. That’s some girthy science.

What’s more, the Very Large Array dishes sit on tracks, so they can be moved around into many different configurations. Given that the array is located in New Mexico, I assume several of those configurations spell out “BEAT ARIZONA” — but still. Moving the component parts around is pretty nifty. It’s like Puppetry of the Radio Antennae over there.

All of those dishes and formations give the Very Large Array remarkable telescoping power. The data from each dish is combined and calibrated to give the resolution of a single dish 22 miles across, and the sensitivity of a dish more than 400 feet in diameter. Some people say that “big things come in small packages”. Clearly, these people aren’t packing a Very Large Array in their arsenal. Because with these telescopes, a bunch of reasonably small packages add up to find some really big things.

How do they do that? By multiplying the radio wave signals captured by each antenna and studying the interference patterns that emerge from the combined data. This technique of interferometry relies on the Fourier transform — which sounds very French and very complicated — to accurately find and track radio sources throughout near and deep space.

And by “radio sources”, I don’t mean Bill and Marty on the KBBL morning show.

Rather, the Very Large Array has been used to study star formation at the center of our galaxy, explore galactic gas clouds, track electron beam bursts in the sun and investigate black holes, quasars, pulsars, gamma ray bursts and more. In 1989, the array was even tuned to listen to radio signals coming from the Voyager 2 space probe as it zoomed past Neptune. I wasn’t even aware NASA had imprisoned a ham radio buff on Voyager 2, but apparently so. Hey, good for them.

But being “very large” doesn’t help you do everything. Even though the Very Large Array featured prominently in the movie Contact, it’s not actually used on a regular basis in the search for extraterrestrial intelligence (SETI).

(That’s okay, though. I’m starting to suspect Jodie Foster isn’t a real astronomer, either. We know she’s not a poet, obviously. But past that, I have my doubts.)

Limitations aside, the Very Large Array’s radio-based interferometry has uncovered a number of fascinating scientific discoveries since coming online in 1980, from the presence of water ice on Mercury to the first detection of radio waves accompanying a gamma ray burst to the discovery of the first “Einstein ring” gravitational lens. A complete overhaul and digital upgrade in 2012 — when it also added the Jansky name to the official title — prompted the National Radio Astronomy Observatory (NRAO) overseers to declare the system significantly improved, and dub it the Expanded Very Large Array.

Me, I would have gone with “MAGNUM“. But what do I know? My array isn’t nearly as large, and can’t even pick up local FM stations.

I’m blaming shrinkage.

Image sources: Big History Project (Very Large Array), Portigal (“Giiiiiirthy!”), QuotesGram (Jodie, not a poet), The Ruddy Duck (shrinkage!)

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· Categories: Biology
What I’ve Learned:

Yersinia pestis: A plague on pretty much ALL the houses, really.
“Yersinia pestis: A plague on pretty much ALL the houses, really.”

Science has helped us to cure a few infectious diseases over the years, like smallpox and polio — and measles, if you live far enough away from Jenny McCarthy. But many dangerous diseases remain, and threaten us all in one way or another. Influenza, for instance. Tuberculosis. Adam Sandler movies.

Also on that list is a name you may not recognize, but which has terrorized the earth for thousands — and humans for hundreds — of years: Yersinia pestis.

That may sound like the name of a Bond villain’s girlfriend, or that animated Disney lady with a grudge against spotted dogs. But it’s actually worse. Much worse.

Yersinia pestis is a species of bacteria, and the disease it causes has been called many things through the centuries. The Plague of Justinian in the 6th century AD. The Black Death in late Middle Ages Europe. Then the Great Plague of Seville, the Great Plague of London, the Russian Plague of 1770-72 and the worldwide Third Pandemic, among many others. At any time, the name changes based on where in the body Yersinia pestis makes its home: pneumonic plague in the lungs, septicemic plague in the blood and bubonic plague in lymph nodes.

Today, we just call it “plague”. Maybe we got lazy with the naming in modern times. I blame Twitter.

No one knew exactly what caused all of these outbreaks until 1894, when Pasteur Institute scientist Alexandre Yersin discovered the culprit bacterium during a plague epidemic in Hong Kong. The species was later named after him; that’s where the Yersinia comes from.

(If the pestis part comes from being a “pest”, that seems like a colossal understatement by whomever is naming these things. A housefly is a pest. Rob Schneider is a pest [who apparently lives too close to Jenny McCarthy]. Yersinia pestis has killed tens of millions of people and once wiped out a third of the European population.

It seems like that rates at least a “Yersinia bothersomeis“. I’m just saying.)

As a bothersome-at-least pathogen, Yersinia pestis has been the subject of much study by modern scientists. Genomes of two of the three known subspecies have been fully sequences, and the genes making these bacteria more virulent than closely-related Yersinia species are well understood. The cycles of infection have been studied, as well — from the fleas harboring bacteria that spread the disease among animals via bites, to rodents like rats and prairie dogs that serve as “reservoir hosts” maintaining bacterial populations, to humans — where Yersinia pestis really gets nasty.

In people, the bacteria survive by following the “best defense is a good offense” strategy. Rather than hiding from our immune system cells, Yersinia pestis meets them head-on. It invades white blood cells, and suppresses the body’s ability to mount an immune response. The bacteria can also kill certain immune cells by injecting proteins directly inside that form pores in the outer membrane, so the insides leak out. Even at a subcellular level, Yersinia pestis plagues are horror movie-level gruesome.

As a final insult, the bacteria often set up shop right in lymph nodes, centers of immune system function. You’d think it was enough to spread all over your body and possibly kill you, but no — Yersinia pestis also wants to rub it in your face.

Luckily, modern science also has a fairly good handle on how to treat the plague. Caught early enough, Yersinia pestis infections respond to antibiotics, and research is ongoing using specific bacterial proteins to make a preventative vaccine.

Still, we’re unlikely to wipe Yersinia pestis completely off the map any time soon. Cases are still reported occasionally today, and recent DNA sequencing performed on material from a 20 million year old fossil flea turned up Miocene Era Yersinia pestis sequence. It seems the world has suffered this “pest” for many, many years and probably will for many, many more to come.

Just like Adam Sandler movies. Sigh.

Image sources: IFLScience (Yersinia pestis micrograph), Wired (Sandler, shocked), Mickey News (Cruella, looking cruel), ETrueHollywoodNonsense (a grinning clueless pesky baboon — and also, an orangutan, I think)

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· Categories: Physics
What I’ve Learned:

Joule: like a newton, with more juice.
“Joule: like a newton, with more juice.”

My introduction to the joule was unkind. I was sleeping peacefully through an applied physics class when the professor slammed my textbook shut and growled:

Well, you must know all of this already. So please, oh bored one, define joule for the class.

I was still waking up, but I thought I heard what he said. Seemed an odd request, but I gave it a shot:

How can you define her, really? Is she a songwriter? A singer? A poet? She covers all the bases, really.

Prof: “Not Jewel, you ninny. Joule, the unit of energy.”

Me: “Yes, exactly. She’s a big unit of energy. A real force of nature.”

Prof: “Oh, go back to sleep. I’m tenured; I don’t need this shit.”

In my defense, this was physics class. No one told me there’d be homophones.

Later — after failing the test it was on, obviously — I learned something about the joule. And I discovered I wasn’t that far off, after all. As a unit of energy or work, a joule really does cover all the bases. It’s something different to everyone, defying definition. Or at least, requiring lots of different ones. Like these, for instance:

  • a joule is a force of one newton applied over one meter
  • a joule is also one coulomb of electrical charge moved through a potential difference of one volt
  • too, a joule is one watt of power produced for one second
  • or if you prefer, the kinetic energy of a two-kilogram mass moving at one meter per second.

The joule is other things, too. Anything that takes work or energy can be expressed in joules — it’s just as versatile as Jewel herself. Singer-songwriter. Poet-feminist. Yodeler-snaggly-teeth-owner. It’s all there.

Of course, you should also know the scientific unit conversions — very handy when talking to someone in a different field. For instance:

0.738 Jewels = 1 Alanis Morissette
1.402 Jewels = 1 Sheryl Crow
1 Jewel + 1 Tom Waits / 1 Joni Mitchell = 1 Melissa Etheridge
1 Jewel + an excess of poor decisions + a truckload of meth = 1 Courtney Love

Okay, maybe these aren’t “scientific” conversions, exactly. But it’s a roller coaster of a Spotify playlist, anyway.

Back in actual science — and around the household — the joules get passed around a lot, too. A dietary calorie is equivalent to 4.2 thousand joules. One kilowatt hour of energy is 3.6 million joules. One of your air conditioner’s BTUs is just over a thousand joules. And a ton of TNT will release a hair over four billion joules, if not treated with care.

(Unlike Jewel, who would just release a song or two complaining about being wronged. This is why you never see TNT in the recording studio.)

Because the joule is a part of the International System of Units, it’s the go-to nomenclature in scientific circles for quantifying work or energy. It’s named after James Prescott Joule, a 19th century British physicist, brewer and early researcher of thermodynamics. So he was pretty versatile himself.

On the other hand, nobody’s nominating James Prescott for a Grammy Award, so I stand by my mix-up in class. But the link to pop culture led me to learn more about joules, at least, so that’s something. If they ever name a unit of measurement after prominent Siberian researcher Nikolas Minaj, or early Swedish physicist Sven Bjornson von Foofighters, then maybe we’ll all learn something.

Actual Science:
Science WireWatt’s a joule?
BBC / GCSE BitesizeWork and power
Physics CentralHow long would you have to yell to heat a cup of coffee?
Magnet AcademyJames Joule

Image sources: WikiHow (joule calculation), Oh No They Didn’t (sparkly Jewel), WikiHow / Redbook / Fact Mag / Wall Street Journal / Concrete (Jewel calculation), 3 News/Australia (less-than-sparkly Love)

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

Wild type: tame on the outside, tamer on the inside.
“Wild type: tame on the outside, tamer on the inside.”

You would think the term “wild type” would describe the craziest, wackiest, furthest-out-there members of a species. Teen wolves. Mutant carny folk. Donald Trump.

But no.

In genetic terms, “wild type” refers to what you’d find “in the wild”, meaning the usual, most common, textbook examples. The ho-hummers. Been there, seen that.

When biologists describe things as wild type, they’re typically referring to one of two things: genotype or phenotype. The words look and sound nearly the same, but there’s an easy way to keep them straight:

Genotype starts the same way as “gene”, and indeed refers to DNA sequence, where genes live. A wild type genotype is one that matches the sequence most commonly found in the population. So what are you called if you have a different sequence, and your genotype varies from the norm? A mutant.

Not in a bad way, necessarily. But a mutation — either in one of your cells, or in one of your ancestors’ cells which was passed on to you — is how variation gets into genetic sequence, and those variations are tremendously important. Without mutations, we’d all have the same DNA. We’d all be susceptible to the same diseases. We’d have no flexibility as a species to survive. And we’d only have Teenage Ninja Turtles movies. Who the hell would watch those?

(Of course, according to Gattaca, we’d also all look like Jude Law and Uma Thurman. I’m sure there are downsides to that, somehow. I’ll let you know if I think of any.)

Then there’s phenotype, which starts with “phen”, so the easy way to remember that is “it’s not the ‘gene’ one”. Or make up something about “phenomenal”, maybe. Or “phenylalanine”. I don’t know. What am I, your mnemonics coach?

What phenotype refers to is outward appearance or traits. One or more DNA sequence changes (or genotypes) may lead to noticeable physical changes, or phenotypes. In fruit flies, for instance, there’s a gene that controls eye color. Certain genotypic changes, or mutations, in that gene lead to a phenotypic change: instead of beady little red eyes, the flies have beady little white ones.

Not as dramatic a physical change as you get from frappe-ing a fly’s DNA up with Seth Brundle’s, perhaps. But still, a distinctive phenotype — one for wild type, and one for mutants.

In the phenotypic sense, there is no single “wild type”. No one set of characteristics is standard, with offshoots of eye color and skin shade and curliness of hair radiating from it. You can compare variations to each other, but there’s no reference person or animal or bacterium to call ideal.

Likewise, you can come up with a “reference genome” for a species — and people have, for humans and fruit flies and rats and plants and plants and hundreds of other species. But each of these is just an average of the DNA that’s tested. One particular genotypic locus might have a certain sequence in fifty-one percent of the population, so it becomes “wild type”. But everyone else is then a “variant”, and none of us have the same set of millions of variants currently known. We’re all mutants, if you compare our DNA to the human reference genome, though we’re considered wild type in the majority of genomic positions.

Well, most of us are. Not counting Teen Wolf. Or carny folk. Or Trump. The only “wild type” of thing about them is their hair. Their scary mutant hair.

Actual Science:
Science EncyclopediaWild type
University of MiamiWild type vs. mutant traits
The ScientistGM mosquito cuts wild-type numbers
UCSCThe biology of the banana

Image sources: IJMM (wild type vs. mutant sequence), Geek History Lesson (Michael J. Wolf), Junkee (Teenage Wild Type Ninja Turtles), More Than Words (hairpiece with a Trump problem)

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XOR


· Categories: Computers, Mathematics
What I’ve Learned:

XOR: 'THERE CAN BE ONLY ODD NUMBERS OF THINGS!'
“XOR: ‘THERE CAN BE ONLY ODD NUMBERS OF THINGS!'”

If you look closely enough, even really complicated mathematics breaks down into simple logic. And if you look at simple logic closely enough… well, it’s really freaking complicated.

Take the word “or”. We use “or” between things all the time. Cake or pie. French fries or onion rings. Coffee, tea or milk.

(And also between things that aren’t food, probably. I skipped lunch, so I’ve got a bit of a one-track stomach right now.)

Mostly, our “or”s mean you can have one thing or the other — but that’s not always true. This is the 21st century, and we’re in ‘Murrica, dadgummit, so if you want half fries and half rings, you can have it. Milk in your coffee? No problem. You want a pie baked inside a cake, on top of another cake with a pie in it?

Well, of course you do. Because ‘Murrica.

These ambiguous “or”s are fine in conversation — and in diners, bakeries and burger joints, apparently — but they won’t do when it comes to math and logic. For that, you need something more specific. More restrictive. You need XOR.

XOR — or “exclusive or”, if you like — is a logical operator that denotes the less generous sort of “or”. XOR is “or” with a mean disciplinarian streak. It’s the Ebenezer Scrooge of “or”. The angry ruler-wielding Catholic nun of “or”. And when separating two choices, XOR is the big ugly punk highlander of “or”: THERE CAN BE ONLY ONE!

In logical terms, a pairwise XOR represents the choice of “A or B, but not A and B”. But this is logic, so it’s not that simple. You can slip XORs between any number of items — Bob XOR Carol XOR Ted XOR Alice, for instance — and in the general case, XOR is true when an odd number of things are true.

So XOR isn’t totally stingy, but you might not like the results. You can have any one of coffee, tea or milk — or you can have all three mixed together, because three is an odd number. Wake up and smell that in the morning, I dare you.

Outside of pure math operations, XOR has some interesting practical uses. It’s used when generating random numbers to ensure that “random” really is random. XOR is also used in cryptography, sometimes alone as a simple “XOR cipher”, but usually as part of a more complicated system.

And there’s something called an “XOR swap algorithm”, which I don’t actually understand at all, but I assume has something to do with Bob caking Alice’s pie while Carol milks Ted’s coffee. Or something.

The important thing is, there’s “or” and then there’s XOR. So if you’re offering someone a choice and feeling particularly stingy, Scroogy or Highlander-y, remember the “exclusive or” that the math and logic types use. Because “or” is fine — but XOR is delicious.

Actual Science:
University of Maryland CSThe magic of XOR
MalwarebytesNowhere to hide: three methods of XOR obfuscation
Logic.lyXOR gate
CCSIThe XOR problem and solution

Image sources: PSU / Teaching with Databases (XOR Venn), Flying Monkey Philly (pumpple cake, which is somehow actually a thing), The Daily Banter (shiny happy Kurgan), 429 (B, C, T, A)

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