You're Welcome

Sunday

My mom contacts me to tell me that my sister, Naomi, and her band The Arbitrarys are in trouble. It was pretty much the same trouble that they were in a few days before: the transmission in their van went kaput in Merritt, and they needed another vehicle to get to their gigs. They had already borrowed a vehicle from our aunt Sandy and uncle Joe in order to go to Vancouver Island, but now they needed a new vehicle fortheir trip back north. That's where I came in. . .

Monday

I drive 730 kilometers from PG to Surrey in our Suburban, which I am to give to Naomi. I leave PG at about 10:30 and arrive at a quarter to seven. Excluding bathroom breaks, snack breaks, and lunch, that leaves roughly eight hours of actual driving time. Everyone at Sandy and Joe's is surprisingly impressed by how "fast" I got to Surrey-- I'm more impressed by the fact that I managed to do this trip on 80 litres of Diesel, about half a tank on the Suburban. It was not an especially fun drive. I was so concerned with getting to Surrey at a reasonable time that I couldn't really sit back and enjoy the view (I considered visiting Chasm, about fifty kilometers north of Clinton, but decided against it.) One thing that struck me, though, was the absence of snow caps on the mountains of the Fraser valley, something I've noticed in a mountains near PG as well. In all the years I've gone down that stretch of road, never have I seen the mountaintops so bare. Maybe there's something to this global warming thing. . . .

I arrived just in time to join the gang for dinner. My cousin George recounted how he flipped over his quad and broke his left arm, and injury that required him to have pieces of metal surgically inserted into his arm to keep the bones of his forearm in place. Apparently, this is only the latest in a series quad flipping accidents of which George has been a part. George. . . he's a character!

After dinner and conversation, me, Naomi, Josh and Robin took the Suburban on a drive to Vancouver. After visiting Stanley Park we went downtown, where we got Starbucks and ice cream. While I was waiting for everyone else, a charming older lady with a large bruise across the right side of her face asked if I would like to buy her a pint. Romance.

Owing to Naomi's shitty directions, we didn't get home until midnight. . .

Tuesday

Once we did, Sandy set up our beds for the night. I had been under the impression that I would be getting a guest room, but unfortunately, all that Sandy could manage was foamys and sleeping bags far too small for my frame. I realize Sandy was on very short notice and did her best with what she had, but that said, putting a blanket on the carpet would have done just as well as the foamy that I had been given. Of course, Naomi and Josh got the big inflatable thing. You know, they needed rest after their long day of driving a distance roughly equal to Germany.

Joe got up at five in the morning, and since I was sleeping in the living room next to the kitchen where Joe was preparing his breakfast, I did too. Sandy took me to the airport and by 10:00 in the morning I was home. Fifteen hundred kilometers in twenty-four hours.

So, yeah. You're welcome.

(Note: Naomi did thank me numerous times.)

(Also: A.J., I got you're comments, and replied to them in the same comment thread.)

Tycho Crater Imaged

Remember Selene/Kayuga, that probe Japan sent into lunar orbit? Well, using photographs and altitude measurements taken by the probe, scientists at the Japanese Space Agency have constructed a 3D map of the lunar crater Tycho.

Click here for a video. It's a big file, but it's worth it.

(Thanks Bad Astronomy)

Free Electron Lasers, Part 1

One of the complaints that could be made about my blog-- if I had any readers to complain in the first place-- is that I don't blog about physics. Well, that's about to change*.

This past semester I took a course in laser sensor technology, with a focus on the industrial applications of lasers. The professor of the course, Dr. Matthew Reid, has developed technology that uses photonic radiation in the terahertz spectrum to scan pieces of wood and measure their density, moisture content, fibre structure, etc.. This info can then be used to determine the quality of that wood. His work has attracted attention from companies like Boeing, as well as local and provincial media. I only mention this to give background on why the course is being offered in the first place-- though being taught by a minor celebrity is worth mentioning as well.

Anyway, one of the course requirements involved writing a report and doing a presentation on some new laser technology which can be applied to industry. I gave my presentation on Wednesday the 9th, and I won't get my mark on the presentation and report until Monday the 14th. Still, I thought I'd blog about the technology that I looked at-- the free electron laser.

The difference between a conventional laser and a free electron laser, or FEL, boils down to how each device generates light. All lasers rely on a "gain medium" to produce light. In conventional lasers, the gain medium consists of some energized material that emits photons through a process called "stimulated emission." See the picture below(Source)

Light emitted in this manner is coherent, that is, all the photons have pretty much the same frequency(the photons can never all be at one and only one frequency-- this violates the laws of quantum mechanics-- but the spread or "bandwidth" is relatively narrow). This is what differentiates laser light from normal light.

FEL's also generate coherent light, but with a process completely different from stimulated emmission. First, some backgorund. The laws of electromagnetism say that whenever a charged particle, like an electron, is accelerated, it will emit a photon. One way to accelerate an electron is to use a magnetic field. Any electron travelling through a magnetic field B with some velocity v will undergo an acceleration a(using B to refer to Magnetic fields is just one of the many useful conventions we physicists have adopted). The magnitude of the acceleration-- and hence, the frequency and intensity of light emitted-- depends both on the velocity v and the magnetic field B, as well as their relative directions(for best results, v and B should be perpendicular; it doesn't work at all if v and B are parallel). In other words, if we can control the magnetic field strength and the speed electrons, we can determine what kind of light is emitted.

One can get high intensity light when the electron speed v is very, very close to the speed of light. Light produced this way is known as "synchrotron radiation", because it is most commonly generated by synchrotron accelerators that are used to push electrons to near-light speeds. To get even higher intensities, the ultrafast electrons are forced through an insertion device, which subjects the electrons to an oscillating magnetic field. In other words, the electrons are "wiggled" to produce light. See below for a picture(soruce)


The wiggly yellow line is the electron stream. The cones coming out of the wave's peaks and troughs are the emitted photons. As I mentioned before, the light produced this way is coherent, so it can be used to produce laser light.

So why use this process in the first place? There are a few reasons.

Remember when I said that the frequency and power of the light emitted this way depends on the electron velocity and magnetic field strength? Well, the magnetic field strength of the insertion device can be controlled by outside operator. This means that the frequency of the laser can be adjusted or "tuned," along an entire spectrum, depending on the laser design. The frequency of light emitted by conventional lasers, on the other hand, depends on the material used in the gain medium, and cannot be changed. This gives the FEL a huge advantage over conventional lasers.

Using this process also allows light to be generated at frequencies that could not be reached by conventional means. For example, x-ray laser light can only be produced by FELs. This type of lasing has been demonstrated at the Spring-8 accelerator in Japan(here's the link).

As well, the laser light is very intense. The Jefferson Lab FEL, for instance, produces light at an average intensity of 15000 joules per second (here's the link to Jefferson).

Finally, FEL's are able to generate very short width laser pulses at a very high rate. What does this mean? Well, many laser applications depend on the ability to generate very brief bursts of laser light with extreme intensity, as opposed to a constant stream of photons. By using pulses instead of a continuous photon stream, one can generate huge peak power(millions to billions of joules per second(!), depending on how short the pulses are). Conventional lasers need special devices(Q-switches, mode-lockers) to generate pulses, but FELs can do this on their own. And when I say they generate "very short width" pulses, I mean pulses less than 0.000000000001 seconds long! This amount of time is so short only an incredibly silly name can describe it: "subpicosecond". By comparison, Q-Switching a conventional laser can produce pulses on the order of "only" a nanosecond (0.000000001 s).

That's the basics of the FEL. I'll post up a blog entry on the FEL's applications sometime next whenever-the-hell-I-fell-like-it. For now, I'll close with a video of the Jefferson FEL burning a hole through a slab of plexiglas. Enjoy!

*Hear that sound? That's the sound of critics being silenced!


(OtnqJUXZLjM)

Blog Surfing

Whenever I sign into Blogger to write another one of my incredibly insightful blog posts, I notice a sort rolling list of blogs which have been updated within the past minute of my logging on, give or take. So I decided to click through some of these random blogs. This is what I found:

Turkish Anti-Israel Islamic Terrorists!

(After thinking about it, I decided not to post the link. I don't wanna endorse these guys. . . or look to whomever is watching like I endorse these guys.)


Some family by the name of Shakespear.

http://theshakespearpeople.blogspot.com/


Ceramics and Violinists.

http://digitalliz.blogspot.com/


Russians.

http://kabinetist.blogspot.com/


Either a news blog or a porn porn blog.

http://mlm-riset321.blogspot.com/


English language site of someone who appears to a Chinese business student.

http://haohan888.blogspot.com/


The Negro Diaries?

http://lilulandia.blogspot.com/


A picture a day.

http://veggiewannabe.blogspot.com/


A site called "Oscar Video" that seems to just link to a streaming video site.

http://osnewsboargin.blogspot.com/


Scandinavian!

http://morslillaolle.blogspot.com/


Liberta-- That's Spanish. That's all I can tell.

http://futurovegetariano.blogspot.com/


A porn site.

No link. I'm not linking there. It's boring anyway.


Movie News. In English AND Spanish! They seem to be really interested in a Neil Armstrong movie.

http://novidadescinema.blogspot.com/


Cancer.

http://mesothelioma23.blogspot.com/


A Swedish(?) website with an English title: Dancing in an Ocean of Roses!

http://kiimbeerly.blogspot.com/


That's MISTER Forex!

http://misterforex.blogspot.com/


Thai.

http://downmerngc.blogspot.com/


Someone who wonders why he's not a failure.

http://viewfromvantucky.blogspot.com/


Chinese site, English Language.

http://lovetheworld999.blogspot.com/


Virginia Real Estate. No, really.

http://estate.focusfinal.com/virginiarealestate/index.html


Pharmaceuticals!

http://viafrailaellis.blogspot.com/


His Mobile Blog.

http://toybet187.blogspot.com/


Another turkish one, but this time not radical Islamists.

http://yelkencilerlokali.blogspot.com/


Someone from Israel.

http://ferociouspixie.blogspot.com/


David Lindsay.

http://davidaslindsay.blogspot.com/


Alright. Enough is enough. I think we can all agree that I have officially wasted your time.

Greatest Assignment Evarz!1!

One of my duties as a grad student is to mark undergraduate physics assignments. This is usually a pain in the ass, but every so often I get an assignment that not only sucks, but is actually entertaining.

In this case, it was a doodle in one of my Phys 111 assignments. It shows two situations, one in which two boys are writing on a chalkboard, and one in which one boy and one girl are writing on a chalkboard. In the first case, one of the boys has claimed that the indefinite integral of x^2 is Pi (it's not, just so you know). The other boy then says "Wow, you suck at math!"

In the other case, the girl has written the exact same thing. The boy in that case says "Wow, girls suck at math!"

Simple. Beautiful. And with logic perfectly applicable to many other situations.

For example:

#1

MAN HOLDING BIBLE KICKS PUPPY.

MAN #2: You're an asshole!

#2

MAN HOLDING THE GOD DELUSION KICKS PUPPY.

MAN #2: Atheists are assholes!

(Note: Replace "The God Delusion" with "The Koran", "Atheists" with "Muslims" and, if you like, "Assholes" with "Terrorists" and it works just as well)

Or how about:

#1

WHITE MAN ROBS BANK.

OLD WOMAN: What a horrid fellow!

#2

BLACK MAN ROBS BANK.

OLD WOMAN: Oh, those Negroes.

OLD WOMAN CHCUCKLES.

#3

ASIAN MAN ROBS BANK.

OLD WOMAN: INTERN HIM!!!

Don't you just love it when your entire worldview comes in "Fill-in-the-Blank" form?

On the Eve of Your Birthday. . .

This post is directed toward my sister, Naomi. But y'alls welcome to read it if you like.

Hi, Naomi. This is normally the post where I would post up stupid YouTube videos of idiots doing birthday raps. But today, I have a confession to make. It's a confession of a secret kept by the entire family, and they won't be happy that I told you, but goddamn it, I love you too much keep this from you any longer.

Here it goes. For the past twenty years you've been told that you were born on the late evening of February 28th, 1988. This is a lie; you were actually born a few minutes after midnight, February 29th. With the help of our doctor, who aided in falsifying your birth certificate, we faked your birthday to prevent you from having to face the stigma of being. . . a Leap Year Baby.

All your life, we've tried to convince you that you were bon on the twenty-eigth of February, going so far as to hold fake birthday parties and give fake birthday presents. Mom, Dad, the doctor, and me were the only ones to know about this. . . until now.

Naomi, you would be twenty today. On the eve of your birthday, February 29th, I think it is time for you to know. . .

YOU'RE FIVE!!!

Star Wars. . . Nothing but Star Wars . . . Give me Those Star Wars. . . Don't let them E-e-e-e-e-e-e-e-e-end!*

I'm in my mom's office, pissing away reading break and waiting for word on our cat Cedric, who's undergoing balldectomy getting neutered at I speak. To pass the time (which I could've been spending doing marking. . . or something-- anything-- out in the open air) I thought I'd write about the lastest bit of space news I've come across.

Sometime last night, while the rest of the western hemisphere stood in the freezing air waiting for a lunar eclipse, the US Navy shot down one of its own country's spy satellites. The satellite was in a decaying orbit, and some believed that it might be able to partially survive re-entry and crash somewhere on Earth--more specifically, somewhere on Earth that's Russia, China, North Korea, or Iran. There's also speculation that the spy satellite contains large amounts of unconsumed hydrazine rocket fuel, which might pose an environmental hazard (indeed, the fact that the fuel was unconsumed, and hence unable to laung the satellite to higher orbit and greater velocity, might explain why it is falling in the first place).

Naturally, the United States government is keeping mum about this whole affair. After all, government and military secrets are at stake, and besides, the whole thing is so embarrasing that. . . oh look, the Department of Defence posted a video of the Navy blowing up the satellite:



Apparently, the cloud of gas that appears after the explosion was indeed unburned hydrazine, according to a spectral analysis.

Now, I can understand the DOD posting the video in order to quell the public's worries of, how shall I put it, a KILLER FUCKING SATELLITE:



But, being the paranoid sort that I am, I couldn't help but wonder if there was something else going on here. Then I remembered that China, just one month ago, also blew up a satellite with a ground-based missile:

WASHINGTON (CNN) -- China last week successfully used a missile to destroy an orbiting satellite, U.S. government officials told CNN on Thursday, in a test that could undermine relations with the West and pose a threat to satellites important to the U.S. military.

According to a spokesman for the National Security Council, the ground-based, medium-range ballistic missile knocked an old Chinese weather satellite from its orbit about 537 miles above Earth. The missile carried a "kill vehicle" and destroyed the satellite by ramming it.

The test took place on January 11. (There was a link to a video here, but I cut it out. You can find it at the main site.)

Aviation Week and Space Technology first reported the test: "Details emerging from space sources indicate that the Chinese Feng Yun 1C (FY-1C) polar orbit weather satellite launched in 1999 was attacked by an asat (anti-satellite) system launched from or near the Xichang Space Center."

A U.S. official, who would not agree to be identified, said the event was the first successful test of the missile after three failures.

The official said that U.S. "space tracking sensors" confirmed that the satellite is no longer in orbit and that the collision produced "hundreds of pieces of debris," that also are being tracked.

So. . . is all of this just an outer space pissing contest between China and the United States? Are we about to enter a new Cold War in Earth orbit? The U.S. has issued diplomatic protests, and President Bush has been waving that little of sabre of his over issues of American outer space policy for some time now:

The United States logged a formal diplomatic protest.

"We are aware of it and we are concerned, and we made it known," White House spokesman Tony Snow said.

Several U.S. allies, including Canada and Australia, have also registered protests, and the Japanese government said it was worrisome.

"Naturally, we are concerned about it from the viewpoint of security as well as peaceful use of space," said Yashuhisa Shiozaki, chief cabinet secretary. He said Japan has asked the Chinese government for an explanation.

Britain has complained about lack of consultation before the test and potential damage from the debris it left behind, The Associated Press reported.

The United States has been able to bring down satellites with missiles since the mid-1980s, according to a history of ASAT programs posted on the Union of Concerned Scientists Web site. In its own test, the U.S. military knocked a satellite out of orbit in 1985.

Under a space policy authorized by President Bush in August, the United States asserts a right to "freedom of action in space" and says it will "deter others from either impeding those rights or developing capabilities intended to do so."

The policy includes the right to "deny, if necessary, adversaries the use of space capabilities hostile to U.S. national interests."

Low Earth-orbit satellites have become indispensable for U.S. military communications, GPS navigation for smart bombs and troops, and for real-time surveillance. The Chinese test highlights the satellites' vulnerability.

"If we, for instance, got into a conflict over Taiwan, one of the first things they'd probably do would be to shoot down all of our lower Earth-orbit spy satellites, putting out our eyes," said John Pike of globalsecurity.org, a Web site that compiles information on worldwide security issues.

"The thing that is surprising and disturbing is that [the Chinese] have chosen this moment to demonstrate a military capability that can only be aimed at the United States," he said.

Again, maybe I'm being paranoid, but isn't it also strange that just a month later, the U.S. destroys one of it's own satellites, for all the world to see?

But Anyway. . . as long as you're here, read My Story II and give me some input, dammit! I plan to do this for money and acclaim and girls one day!

Links:

Bad Astronomy Blog Article

BBC Online Article on Spy Satellite

CNN Online Article on Chinese Missile Launch


*The title is based on Bill Murray's "Star Wars Song" from the early years of Saturday Night Live. I couldn't find the original clip, but I did find this video by DickSharpe80 which has the song on it.