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Tuesday, December 19, 2006

Where the satellites are...

Check this out.

http://science.nasa.gov/realtime/jtrack/3d/JTrack3D.html/

A window will pop up and ask you if you want to run it. Click yes. You will get a real-time display of all the satellites orbiting the earth. The ring of satellites is the ones in geosynchronous orbit - they stay in the same place in the sky so that you can aim your DirectTV dish once and then forget about it.

You can zoom in and out on the earth and roll it around to find where you are at. Of greater interest is that you can click on a satellite and see its orbit. If you happen to be out shortly after sundown or just before sunup, you can look to see if you can watch a flyover. This is when the sky will be dark, but the satellite will still be illuminated by direct sunlight. It's very cool to watch.

Anyway, it's a cute program and I like to fire it up from time to time.

Monday, December 18, 2006

Polonium 210

I've been meaning to post about the fascinating poisoning of former Russian spy Alexander Litvinenko.

The political ramifications are a bit beyond my understanding, other than the obvious consideration that someone was bold enough to assassinate a political enemy on foreign soil.

Why instead of radioactive poison didn't they just shoot him, disappear him, or run him over? Curious stuff...

What I find fascinating about this case is the technical challenges and genius at the nature of the poisoning, as well as the choice of the radionuclide, Polonium 210 (or Po-210 for those in the nuclear biz).

I've done a bit of reading on Po-210 since the news of Litvinenko's poisoning hit the wires. It's quite an interesting and quirky nuclide.

Let me start by sharing a little about radioactive decay. There are four basic decay mechanisms for radioactive nuclei, each with distinct mechanisms for releasing the energy of decay. As the mechanisms are distinct, so must be the means for detecting them.

Gamma rays are ubiquitous. These are elecromagnetic waves with very short wavelengths, somewhat shorter than hard x-rays. Gamma rays are usually associated with a neutron decaying to a proton and an electron, or just being fired out of an unstable nucleus. 90-95% of all decays release a gamma ray, and it's probably responsible for most of the background radiation everyone is exposed to, either indirectly from cosmic rays, or naturally occurring radioactive elements.

Biological damage due to gamma rays is not bad, as these things go. They create ions by photoelectric effect, pair production, or by compton scattering. The upshot is that charged electrons (or positrons) are knocked loose and are available to ionize (damage) internal tissues. I think of these as little BB gun shots. A few are not so bad, but a shotgun blast of them is quite harmful. Gamma rays have a biological damage factor of x 1

Sheilding: High density metals are best at absorbing gamma rays. The greater density of the metal increases the likelihood of the above interactions attenuating the gamma ray before it reaches you. The amount of sheilding required depends on the intensity (decays per second), and incident energy of the gamma rays.

Detection: Exept for the weakest gamma rays, which are rare, gamma is easily detected. A simple geiger detector can identify an energetic gamma emitter 10-20 feet away.

Beta particles (also known as electron emission) are also ubiquitous. Most of the known decay mechanisms are beta decays, and are usually accompanied by a gamma ray. Beta emissions are mostly associated with the two highly unstable nuclei remaining after a heavy nucleus is split (fissioned).

ASIDE: The highly radioactive spent fuel from nuclear plants undergoes a phenomenal amount of beta/gamma activity. In fact these unstable fission products generate about 7% of the heat of a reactor at full power immediately after it has been shut down. This heat tapers off over the course of several weeks, but without cooling, this decay heat can melt the a reactor core long after it's been shut down.

Back to beta particles. They are basically exceedingly fast-moving electrons, and because gamma rays cause damage by creating these particles, their biological damage mechanism and severity are the same, x 1.

Sheilding: Beta particles have quite a bit of penetrating power, though nowhere near the power of gamma rays. A 1/4 inch sheet of aluminum is the textbook example of what will stop beta particles from reaching you. Obviously this approach will not work if the beta emitter has entered your body.

Detection: Beta particles are easier to detect than gamma. A gamma ray can pass right through a geiger detector without interacting with a molecule of the gas. A charged beta particle is quite likely to have several interactions as it passes through the gas.

Neutrons: These particles are rare, except within the confines of a nuclear reactor, so I won't go into them in depth. I did want to mention them, as they are what cause atoms to become radioactive, (e.g. emit alpha, beta, and gamma radiation) and cause them to fission. This is important, because this part of what makes the Polonium 210 story so interesting.

Alpha particles are most often associated with heavy nuclei (think Radium, Thorium, Uranium, Radon). An unstable heavy nucleus usually kicks out an Alpha particle and a gamma ray as it seeks a lower (more stable) energy level. The alpha particle is actually just a helium nucleus (two neutrons and two protons), that dropped the electrons as it was blasted out of the nucleus.

Here's what's bad about alpha particles biologically: They have a large +2 electrical charge, and compared to the other decay particles, they are massive. Due to their mass and charge, they ionize tissue quite readily, doing a great deal of damage. In many respects, they are like little nuclear hollow-point bullets. They do not penetrate very far in skin tissue or in air, but are lethal when taken internally.

Sheilding: In general an alpha particle can be blocked by a piece of paper. Taken internally, there is nothing to prevent an alpha-emitter from doing truly massive damage. Alpha particles have a biological damage factor of x 20.

Detection of alpha emitters is not normally difficult. Since most nuclides emit a high energy gamma ray at the same time as the alpha particle, the gamma ray gives away the presence of a radionuclide. Interetingly Po-210 is one of the few alpha-emitters that does not emit a gamma ray during decay. Direct detection of alpha particles is more difficult; due to their large charge, they tend to come to have very short flight paths, even in air. Detectors must have thin windows (mylar) and be very close to the source. Geiger detectors and scintillation counters in close proximity to the source are your best bet for detection of alpha particles

Now that we have the primer on radiation, sheilding, biological damage, and detection taken care of, lets look at how Litvinenko was poisoned:

1) Polonium-210 is an alpha emitter that has a half-life of about 138 days. That means that 138 days after you take it from a reactor, only half will remain, after another 138 days you'll only have 1/4 of it, then 1/8, 1/16, etc, etc. There is no gamma ray associated with this decay.

2) Polonium is exceedingly chemically toxic. Weight-for-weight, polonium is around 5 million times more toxic than hydrogen cyanide, the gas used in state's gas chambers. 50 nanograms will kill 50% of those exposed to it. It accumulates in the liver and spleen where it chemically attacks them.

So what can we deduce about the poisoners' technological infrastructure from the above information?

They have a nuclear reactor (or access to freshly spent nuclear fuel) to even produce Po-210.

They have access to a hot cell which gives them the ability to remotely handle and chemically process highly radioactive spent nuclear fuel to separate the Polonium.

They realize that once the Polonium 210 is ingested, the victim's body will act as a shield to prevent alpha particles from reaching external radiation detectors. No gamma rays will give away the existence of the Polonium.

They understand that the dose of Polonium 210 will kill Litvinenko either chemically or due to the the alpha radiation effects.

Which leaves us with the question of who did it... all I can say for certain is that they have highly developed nuclear technology: Nuclear reactor, fuel handling, and isotope separation. There are a handful of countries and companies that could do this, but only one that had all of that plus a grudge ;)

Yahoo Searches

OK, now I know why I've never fit in socially...

From Yahoo:

Top Searches of 2006
By Mike Krumboltz
Fri, December 08, 2006, 3:40 pm PST

"Yahoo! users searched on all sorts of stories this year, but Britney was the biggest of them all. Despite (or perhaps thanks to) her trainwreck of a personal life, Ms. Spears took home the title of Yahoo's top search of 2006.

While the former Mrs. Federline may have been the most popular, she was far from Search's only story. "American Idol" dominated as expected, the untimely death of Steve Irwin shocked us all, and the Iraq war remained on the minds of many."


I've never really given a damn about celebrities - I don't attach any more importance to their lives than anyone else's. Perhaps less so in in the case of "Idol", Britney and Irwin. Idol and Britney are without substance, and Irwin spent a lot of time provoking wild animals to further his career. It finally caught up with him. His crocs likely would have been happier and better off in their natural surroundings.

That the Iraq war is #4 on the list behind these others isn't surprising. What is surprising is that this horrific event made the top 5. Amazing how ill-informed we are as a nation. With all the information of the world available on a PC, we use it to see what the tabloids are saying in real-time about Britney... and so I'm happy to say I'm not a well-adjusted member of this society ;)

Saturday, December 09, 2006

Favorite quotes

I'm a big fan of the simple wisdom (and humor) expressed in quotes. So just for shiggles, I'm going to post a few of my favorites. I've probably paraphrased and butchered a few of them. In no particular order and certainly not comprehensive:

"Everybody wanna be big, but ain't nobody wanna lift no heavy-ass weights." - Ronnie Coleman

"Only two things are infinite; human stupidity and the universe. And I'm not certain about the latter." - Einstein allegedly said this.

"Two things a man should never be angry at: Those things he cannot change, and those things which he can" - Unknown

"Never take a crap until you get on the clock. Don't break a sweat until you are off the clock. Never get your pussy and your paycheck from the same place" - Blue collar worker's axioms.

"In theory, theory and practice are the same; in practice, they're not" - Yogi Berra allegedly said this.

"A man with one watch always knows what time it is. A man with two watches is never certain" Unknown.

"Economic history is a never-ending series of episodes based on falsehoods and lies, not truths. It represents the path to big money. The object is to recognize the trend whose premise is false, ride that trend and step off before it is discredited." - George Soros

"Hyperbaric surgery (gastric bypass) is the biggest cop-out since suicide was invented." - unknown

Monday, December 04, 2006

Toys for tots and long wheelies

On Sunday a few rider friends and I went on the Toys For Tots ride. It was cool, although us sport bikers were outnumbered about 20:1. The ride sadly was a bit lame. Stop and go on the freeway, and no fast curves. Even getting up to speed on the freeway was a bit dull with 500 hogs cruising up to freeway speed right ahead of us. But hey, it was for a good cause.

After the ride there was a barbeque and sodas were served. It gave me an opportunity to meet some previously unknown sport bike riders, a few of whom also happen to be stunters. The are a group known as the 'bako boyz'.

They have a website that has some pretty wild video clips. Their tutorial "Guide to Wheelies" is a tongue in cheek howler.

The guy we got talking to, named Chris, was quite friendly and outgoing. Toward the end of the gathering, he said "I feel like doing a wheelie". I said "I feel like watching that!" So we all got on our bikes and got the tires warmed up for a few minutes, then he took it out on the freeway, slowed to 45 mph, and popped it up on one wheel and rode for about half a mile. Then he did a stand-up wheelie for us. Cool! Chris BTW is in the video link above, riding the lime-green bike.

Then he told me to do one. So I did a little one - there's a point (well shy of the balance point) where the front wheel really starts lifting quickly, which is where I always back way off and let it drop. He suggested that I back off less and try to find the balance point. And I said, well it's the consequences of not getting it right that scares me the most :) He laughed and we agreed to meet at one of their gatherings soon. Nice guy - really outgoing and likeable. Engaging and fun.

He did mention that once you learn to ride a wheelie you won't be able to stop doing them... He's probably right. I find myself getting bored commuting to work and wanting to blast off real fast or take a corner or something... anything. There's something about having a 400lb vehicle with 150 horsepower that makes you want to use it in excessive ways.

Speaking of which, at one point I was riding quite tamely in heavy traffic, but letting the bike rev a bit over 5000 RPM (about half of what it's capable of), when this little Toyota next to me apparently thought I meant to race. So he stomped on the gas and lurched ahead of me. I didn't bother to snap the throttle open, as I was laughing so hard I nearly peed myself. Unless that Toyota sedan was able to go 0-100 in 5 seconds (something that Ferraris can't do), then he was wasting his gas.

Saturday, December 02, 2006

Guitars

Re-reading that last post brought to mind another thought about music. Namely that for about 25 years I've had an on-and-off thing with playing guitars. Mostly off. I struggle to play well; it's something that doesn't come naturally at all to me. It shows: No Bands, albums, or groupies ;)

In the early nineties I was probably at my best, and tried out for a small garage band. Nervous as all hell (with an uncritical audience of four, hahaha), I didn't perform very well. And not having played much since then, you might call me "Rusty".

But what this post is really about is the guitars I've owned in the past, the guitar I have now, and the ones I'd like to have in the future.

The first one:



A white fender Stratocaster or just "strat". As built, these have three single-coil pickups and a five position selector switch so that you can use any pickup by itself or get a dual input from any two adjacent coils, for a sort of phasing effect. To my ear, selecting two pickups seemed to "muddy" the sound.

I nearly always prefer the bottom pickup, the one closest to the bridge. This is the one that gives that classic biting high and clear Fender sound. Pink Floyd and Clapton solos are a vivid example of the awesome sound these guitars are capable of in the right hands. Man, I think I'm gonna play Floyd's "Wish you Were Here" album whilst I continue to write... ah man. That's almost giving me a buzz! :)

Back to the white strat though. I never did like it much. The intonation wouldn't hold. I don't think that particular one was very good quality. To make it right would have taken quite a bit of expensive professional work and money that I didn't have. In any event I was just a beginner and didn't feel such a big invesment had much merit. So I sold it.

I've since played Strats in stores, and friend's instruments. I liked them better, but never quite as much as the sunburst colored Les Paul, which was the next guitar I bought.


I liked the way this guitar played a lot! It had a nice wide neck that let my fat fingers hit the strings without touching the other strings. That's a good thing if you want to play chords without strings buzzing on you.

What I didn't care for too much about it was the muffled sound. As built, these guitars come with "hum-bucking" pickups, which have dual coils wound counter to one another to cancel out the hum you get feeding back from some amps. A very clean sound, but to my ears it sounds quite muddy. Jeff Beck favors these guitars (kicks butt with them!!!), and I think they're great rhythm instruments. I probably should get another one, because I'm never going to be a great solo player.

The third guitar, a 1985 or 86 sunburst-colored Telecaster "tele" - has a fascinating story.


This guitar has an interesting background. One afternoon while I was still in the Navy and the submarine was in port, my roomate Buff (Big Ugly Fat F**ker - yes he liked to be called that) and I were getting drunk. This was not so unusual. What was unsual was that I decided that I needed a guitar and that he needed to learn how to play the Bass :) Unfortunately for him, he needed no persuasion whatsoever, so we went to a used music store on Broadway street in San Diego. The place had a feel very similar to the famous Ray Charles scene in the Blues Brothers. Back in the 80's, Broadway was quite seedy.



I loved this guitar! Man that thing could ring clear and true and hold a note forever.


Me and Buff spent a lot of time practicing together and actually had guys interested in playing/singing with us! Then I got out of the Navy and we drifted apart. Shortly after this, I got out of the Navy and moved to La Jolla and into an apartment with a guy who'd gotten out a few months earlier... (I'll do a long post on him later - he's an important person in my life).



I ended up meeting a neighbor who worked in construction who also played the guitar. He showed me some interesting licks, and I showed him a few that I'd picked up over the years. I wento over to his apartment and we played together a few times. He was very, very good - which caused me to become discouraged. I was ready to quit, and told him so. (He played a Les Paul) He offered to buy the Tele from me, and I agreed.



15 years later my roommate ran into the guy I'd sold the guitar to. He asked how he was doing. Turns out he was no longer working in construction and was making money as a professional musician. His name is Dean DeLeo. He's the guitarist for the Stone Temple Pilots. I want my damn guitar back... signed :)



The guitar currently own was purchased new down on Sunset strip in Los Angeles. It's a 1990 black tele. I love it except for the color. Teles are frequently used in the new country music scene, much to my dismay. This is a genre of music that's a little too formula for my liking. Johnny Cash and Hank Williams are probably spinning in his graves over what 'country' music has become.

Moving on now to Floyd's "The Division Bell" Friggin' awesome.



My current amp: A Fender Twin Reverb. Cool classic sound. And I have a Morley Fuzz-Wah pedal for when I attempt to play Tocatta and Fugue.


Guitars that I'd like to have someday:


#1 A Rickenbacker 330 or 360 in fireglow color. These are semi-hollow bodied guitars, and give a totally cool sound. Think surf music, or the Byrds. George Harrison played this one. For me, the Romantics "What I like about you" is another example of the classic sound this guitar puts out.

Semi-hollow body guitars look huge to modern eyes, but they have a sound that can't be duplicated by digital signal processors. I think they are fabulous instruments.




#2 on my wish list, The Gibson ES-335 in sunburst color. Another semi-hollow body. BB King made this one famous. I like the sound this one makes. It's clean, if not very biting. I've been to a few jazz concerts and they seem to be favored by the guitarists. I think Spyro Gyra would be a good example of this sound.



All this crap might lead you to think I'm a musician. I'm not. Unfortunately, I don't have natural talent for playing, and have to struggle to learn even the simplest things. But I love music, love guitars, and love playing them.



Friday, December 01, 2006

The THX sound

I use the THX sound for the windows start sound on my PC... Gets me in the proper frame of mind for enjoying gaming or surfing. I try to avoid doing serious work on a PC because there are *way* too many distractions, and I'm easily distracted by shiny objects ;)

As an amateur musician (lousy guitarist - no albums, bands, or chicks) I was absolutely fascinated by the sound, and decided to learn more. So with full credit, here is where I learned about the "Deep Note", as it's called in the industry.