a-ha: Take On Me (1985)

The video has held up surprisingly well over twenty years, despite the female lead’s tragically 1980s hair. It’s a mix of rotoscope and live animation that has lived longer in cultural memory than the movie it’s in part aping, Altered States. Family Guy has even replicated the video’s look, though given how fast they chew through random references, it’s no surprise that they’d eventually have to borrow from the Norwegians.

Gorillaz: 19-2000 (2001)

I really like the animation on the early Gorillaz videos. And I must confess that I never get tired of “objects in the rearview mirror are closer than they appear” riffs. Except when Meatloaf does it. Brr.

Earlier we mentioned that we bought Eli a toy guitar to carry for Halloween as part of his Guitar Hero costume. In the picture below you can see a Guitar Hero guitar/controller for the PS2 game on the left and Eli’s Kidz Beats guitar on the right.

They resemble each other, yes? But a closer look turns up some notable discrepancies.

I had no idea Harmonix and Red Octane were ripping me off like this.

Jessica got me hooked on a crafting blog a while back and I’ve been reading it and several others like it. It’s fun to see what other people are making and what’s out there. Several of the blogs I read are European and there’s even one from Australia so it’s always interesting to see what’s trendy elsewhere and what craft is popular where.

Whipup.net is the one that Jessica originally showed me and they have just completed a couple of posts on teaching prisoners in Britain to quilt. I found it both interesting to see how people are using their crafting abilities to make people’s lives better and incredibly moving to hear the prisoners talk about their new skills.

You can read the two part series here and here.

I got a new red chair for Baby TBA’s room but for now it’s living in the living room. Eli got a new guitar for a Halloween costume prop. Guess which one he’s more excited about?

In this photo, Baby TBA is about three inches big.

Here the heartbeat is 162 beats per minute.

Baby TBA all normal and here’s hoping that I will return to normal shortly. I’m thinking of cooking, so things must be getting better.

I’ve gotten some questions in emails and comments on other sites regarding my EMP discussion. The science is all well and good, but give some practical advice!

See, there’s your problem. You know what we call the practical side of physics? Engineering. And it’s those engineers that build weapons of mass destruction and my orbital death lasers and the like, not physicists. Anyway, I’ll see if I can give more practical answers, but don’t hold your breath.

Does it matter if an electrical appliance is plugged in or not?

Ooh, good question. If you’ve got something plugged in, it’ll likely get more EMP. Power lines can act like antennas and conduct the EMP right into your appliance.

What if the electrical appliance is running?

Mmm, I wouldn’t expect that to make much of a difference.

Hey, in Jericho that lady’s Rolex died from the EMP. Would that really happen?

Most cheaper watches are electronic, and keep time by measuring the piezoelectric oscillation frequency of a little chip of quartz. EMP is likely to zap those kinds of watches. But a Rolex? Those are normally mechanical rather than electronic. The EMP shouldn’t do anything to them.

Would my car still work?

Depends on how old it is. Your fancy-schmancy CPU-controlled electronic fuel injectors are likely to die, as are any other electronics in your car. Older cars are more likely to be okay, since their electrical systems are mostly just wires, like the starter.

Can you fix stuff that an EMP has damaged?

For the most part, no. Well, let me back-pedal some: you can’t fix the individual components, but you might be able to fix the whole device by swapping out undamaged parts. Semiconductors such as transistors and diodes fail by melting internally and causing a short, and there ain’t no fixing that. Capacitors will fail when the EMP-induced voltage is more than the capacitors’ dielectric breakdown threshold, and then they’re useless. If plain vanilla wires are damaged, it’ll be from them shorting through their insulation and into neighboring wires. That’ll mostly happen when the wires are coiled up, like in transformers. Replace the insulation (or, heck, the entire wire) and you should be okay.

Come on, can’t you just tell us what will survive and what will fry?

Not easily. It depends on too many variables. How strong was the bomb? How high was the detonation? Is the equipment inside a building that has a lot of metal in it, which will shield stuff that’s inside? Is the equipment near an unshielded power line?

I can tell you what’ll be zapped first. Semiconductors are the most susceptible, especially low-power transistors. Capacitors are next, then film resistors, then wire-wrapped resistors, then wire-coil devices like transformers and inductors and car starters. So anything computerized or that has a circuit board in it is most susceptible, but your old-fashioned toaster is probably okay.

But if the EMP is strong enough, everything’s going to go. Fuses will blow, circuit breakers will trip, wires will arc, and everyone is out of luck.

The following story contains references to vomit. In fact, the very first sentence of this blog post proper contains the word “vomit”. Read on at your own peril.

At the end of last week we were the House of Vomit. On Thursday Eli got some kind of stomach bug that involved him throwing up every thirty minutes or so. He threw up so much that we had to make a game of it. “Grab your bowl! Can you hit it? Can you keep it all in your bowl? Good job!” And then Misty would run off to have a sympathy vomit of her own.

A number of our friends have been kind enough to supply us with food in this, our time of trouble. Amy and Rick and Jessica and Remy and Hallie have given us dinner, since the smell of food being prepared brings on Misty’s hurling. There’s a narrow window of opportunity for her to eat before, like the Bay of Fundy’s tides, the flow of food will reverse.

Aren’t you glad I keep talking about vomit? Thrill with me, Internet, at our tales of gastrointestinal distress!

Thursday Amy came over with soup. Eli decided to charm her by putting his brain on speakerphone and connecting all of his thoughts together with the word “and”. “I have cars and there is a track in my room and you put them down and they go VROOM and they drive around and around and around and and and you wait and then the light is green and green means go.”

Amy, bemused, asked, “And what does red mean?”

“Red means STOP!”

“And what does yellow mean?”

Eli looked puzzled. “No, not yellow, orange. Orange means GO FASTER!” And he pumped his arms like he was running very fast.

Since I grumbled about how Jericho dealt with fallout and nuclear weapons, I should be happy that the CBS show mostly got electromagnetic pulses correct. Right? Right?

You must be new here. As long-time readers know, I’ll lecture at a drop of the hat. Jericho may have gotten EMPs right, but that’s not enough — you must know why their treatment of EMPs is right.

Yes, I used to get paid for teaching physics. Why do you ask?

Electromagnetic Radiation

To start with, let’s discuss electromagnetic waves, since they’re at the heart of how electromagnetic pulses work. Those of you who remember this stuff from high school or college physics classes may skip down to the next big heading.

Anything that has an electrical charge produces an electric field. Anything that is magnetic produces a magnetic field. Broadly speaking, electricity and magnetism are related. For example, electricity flowing through a wire causes a magnetic field, which is how electromagnets work.

You know how, if you take a rope, tie one end to something, and wiggle the other end up and down, you’ll make waves? You can make waves in the electric field and the magnetic field. The easiest way to do this is wiggle something charged up and down. If you take an electron, which is negatively charged, and move it up and down, up and down, it will make waves in both the electric and magnetic field, just like wiggling the end of the rope makes waves along the rope. In fact, you can just move the electron in a straight line and it will make waves in the electromagnetic field. Those waves are called electromagnetic waves or electromagnetic radiation.

Even if you don’t know it, you’re familiar with EM radiation. The light coming from your computer screen is a type of EM radiation. So are the microwaves that your microwave oven puts out. There’s a whole bunch of those waves. What kind of wave they are depends on how fast the wave is wiggling. If the wave is wiggling slowly, you get radio waves that you can listen to in your car. If you wiggle a little faster, you get microwaves to cook your food. Faster still and you’re into infrared that the Predators use, then visible light, then the ultraviolet light that gives you your tan, and on and on through x-rays and eventually to gamma rays. The faster the wave is wiggling, the more energy the wave has. We call this rate of wiggling the wave’s frequency, and we measure the frequency in Hertz. One hertz means one wiggle per second.

(Note that I’m talking about how fast the wave wiggles back and forth, not how fast the wave is moving. All EM waves move at the speed of light.)

Nuclear Weapons Make EM Radiation

When an atomic bomb goes off, you get EM radiation. The most dangerous are the gamma rays. That’s the radiation that will fry you dead.

The gamma rays also do something else: they knock electrons off of atoms in the air through a process known as Compton scattering. The gamma rays have enough energy that, if they smack an electron, they rip the electron out of the loving embrace of its atom’s nucleus. The end result is a bunch of electrons running free in about the same direction as the gamma rays were originally going. Since the electrons are moving, they make electromagnetic waves. But they don’t just move in a straight line: they spiral around some because they’re in the Earth’s magnetic field. They look kind of like those seeds that helicopter around as they fall. What you end up with is a big pulse of electromagnetic radiation that’s moving out spherically from the nuclear bomb, and that radiation has all kinds of different frequencies. It’s mostly radio waves, which is why the EMP doesn’t really do anything to people.

Why is this a problem, then? Because all of this EM radiation is carrying energy, and it whacks into electronics very very fast. The EM radiation causes voltage spikes that happen in a millionth of a second or faster. Those voltage spikes do very bad things to unshielded electronic components, like heat them up. Semiconductors are toast. Transistors and diodes melt across their junctions. Capacitors explode like popcorn. You can even fry resistors.

Location, Location, Location

So why didn’t this happen to Jericho when the first bomb went off? As in real estate, it’s all about location. If you’re near the ground — 200 meters up or lower — a lot of your gamma rays go into the ground. You get an intense EMP up to around 5 kilometers from the bomb’s location, and less EMP out to 10+ kilometers.

Go higher, up to around 40 km, and you get a different story. I mentioned that the EMP’s radiation travels out from the bomb in roughly a straight line, which is why you have to have direct line-of-sight to the bomb itself to suffer EMP effects. Up higher, you can see it from further away.

But if you really want a strong EMP, you need to get your bomb 40 km high or higher. That’s the high-altitude burst region. The atmosphere is thin, so gamma rays travel far before they start smacking electrons around. The gamma rays that are headed down produce the EMP starting at around 40 km high and continuing down to a height of 20 km. You can blanket a lot more of the ground with EMP if you’re that high, and the EM radiation is very strong.

If you were a mad scientist bent on screwing the US over, you’d need to go really really high. A big hydrogen bomb detonated about 400 km above Kansas would blanket the continental US with an EMP. Of course, the International Space Station orbits some 360 km up, so it’s not the kind of thing small terrorist cells are going to be able to do.

Electrical Shielding

At one point in the episode, Hawkins says that his laptop’s okay because it’s ruggedized. He probably meant that it is shielded, since ruggedization is what you do to mil spec equipment so that it doesn’t break when grunts drag it through mud and over rocks. Of course, Hawkins also said that the EMP would fry anything with a wire, which also isn’t true — your 1966 Ford Fairlane is probably going to be just fine, though you may have to replace some fuses.

Anyway, how do you shield electrical equipment? Mainly with Faraday cages. You make a mesh out of metal that is a good conductor, and the EM radiation is kept outside through the magic of physics. That’s probably how Hawkins’s computer is shielded, though it looked a little thin to be well-shielded.

Nowadays the government is more worried about people spying on their computers by monitoring the EM radiation that it gives off. You can eavesdrop on the radio waves that a computer gives off and reconstruct things like the data being displayed. If you shield a system from emitting such signals, a process known as TEMPEST shielding, you can shield it from EMP damage with a minimal amount of additional work.

Notes for the Picky

Some technical notes for the super-nitpickers. The type of EMP I’ve described above is called HEMP. There’s a secondary effect called magnetohydrodynamic EMP, or MHD-EMP. MHD-EMP occurs because the bomb’s plasma and scattered gamma radiation take the Earth’s magnetic field and gives it a shove, like shaking a taut sheet on a bed. The shove sets up EM waves over two time scales: around ten seconds long and around a thousand seconds long. You’ll sometimes hear that referred to as heave waves or the heave effect, because the Earth’s magnetic field is heaving like a drunken sailor in a storm.

Technical notes for super-super-nitpickers: HEMP isn’t just caused by Compton scattering. The photoelectric effect and pair production also contribute, but Compton scattering is far and away the major source of HEMP.

Heh, heh, I said “hemp”.

So even though I can’t stay awake for more than an hour while sitting, I have managed to read two books about God. One is Mudhouse Sabbath, by Lauren Winner, and the other is Searching for God Knows What, by Donald Miller. These are two of my three favorite religious writers writing right now (the third is Anne Lamott).

Mudhouse Sabbath
Lauren converted to Judaism, but was, in her words, “sneaking around to read the New Testament”, so she became a Christian. This book is 11 chapters on how, if we let it, Judaism can add some very fulfilling meaning to our faith practice. While I enjoy being a Baptist, I do sometimes long for the more ritualistic habits that we just don’t have. This book is a good look at what is different, what Judaism does right, and a bit of how we can add that back into our practice. Lauren is an enjoyable writer and I have also read her book Girl Meets God, in which she details her struggle to become Jewish and then her struggle deciding to become a Christian. I have a lot of admiration for her ability to articulate her choices on faith and I highly recommend both of her books.

Searching for God Knows What
Definitely the harder of the two reads. I actually got a bit bogged down in the middle and I took a break to read Mudhouse Sabbath. The fault, however, wasn’t with Don’s prose but with my inability to stay awake. Did I mention that my awake attention span is that of a gnat’s entire lifespan? (Ok, even shorter than that because they live up to four months.)

Don is particularly gifted in reminding me that our culture is wrong. Everything about the system is messed up and when we focus our attentions on that, we will be messed up too. His gift in this book specifically is that our religion is relational. It is not charts and graphs and systems, it is a personal relationship with God. And any effort to reduce that relationship to charts and graphs and systems takes away from our focus on the relationship. My favorite chapter is the one on morality, and it is a must read no matter what religion you subscribe to. But my favorite section of the whole book comes in the last two pages:

And I go back to Eden, in my mind, to imagine what it is going to be like for you and me in heaven. I suppose it will be a new and marvelous paradise, where love will exist in its purest form, where the beauty of diversity will be understood for the first time, where self-hatred will fade into an agreement with God about the splendor of His creation, where physical beauty will no longer be used as a commodity, where you and I will feel free in our sincere love for others, ourselves, and God. And I suppose it will be heaven that you and I actually understand each other, all the drama of the lifeboat a distant memory, all the arguments we had seeming so inconsequential, and the glory of God before us in all His majesty, shining like sunlight through our souls. This will be a good thing, my friend.

The Pinker Tones: Karma Hunters (2006)

Get this out of your head. I dare you. Then remember: you gotta vote for the Instant Karma Party right now.

The Decemberists: Sixteen Military Wives (2005)

The genius of this video is recasting UN-style political wrangling as a battle among high school cliques. Watch how sanctions, weapons inspections, and more are translated into school events.