What makes a rifle a rifle?

I recently learned what the term “rifle” means. It turns out that it’s far more interesting than “gun with a long barrel,” which was my previous definition. Instead, it represents a mechanical innovation. The long barrel contains spiraling grooves on its inside, such that the raised parts of the grooves make contact with the bullet and impart spin to it.

“Like throwing a football?” I wondered, and sure enough, wikipedia uses that exact analogy! The spin gives the projectile additional stability and therefore range (and precision targeting).

The term “rifle” comes from the French rifler, a verb that means “to graze or scratch”. The rifles, then, are the spiral grooves or scratches — and the gun originally was called a “rifled gun.”

So a rifle does have a long barrel, to accommodate the spiral grooves and enough time to spin the bullet (>100,000 rpms!). But it’s what’s inside that counts.

Earth’s quasi-satellites

How many moons does the Earth have? Just one, of course. But I recently learned that right now the Earth also has five natural quasi-satellites. The companion bodies orbit the Sun with the same period that the Earth does, but with a different eccentricity. Our five quasi-satellites are 3753 Cruithne, 2002 AA29, 2003 YN107, 2004 GU9, and 2010 SO16.

Here is a depiction of 3754 Cruithne’s orbit:

These orbits are not stable over the long term (with respect to the Earth) because they lie outside the Earth’s Hill sphere, its region of moon attraction. Eventually they’ll move on to other orbits. But for now, we have these five extra companions in our journey around the Sun.

Olympian wonders

Last weekend, I took the train north to Olympia, WA, to visit my friend Marcy. She put together an action-packed weekend with tons of new experiences and fun times. The list of “firsts” for me included:

  • Eating Voodoo Doughnuts that I picked up in Portland during the train’s stopover there, at Marcy’s suggestion. My favorite was the butterfinger one. Yum!
  • Attending a punk house show (that’s when a collection of bands show up at someone’s house, set up in the living room, and play for the benefit of a group of strangers who’ve also shown up). Imagine a house painted completely black (with some wood trim), decorated with things like a poster of Shirley Temple with “SHIRLEY’S FIRST BLACK EYE” written on it, a slouched crowd of smokers out on the stoop, and punk music booming from inside. A sign on the bathroom door urged you to pee outside. There were three bands that evening, the best one being TacocaT — aside from scoring points for their palindromic name, they write cute/edgy songs mainly from a girl perspective. Check them out!
  • Playing Urban Golf through the streets of Olympia. This involves dressing up in your best argyle, tweed, or houndstooth and hitting nerf balls with golf clubs on a predefined course. Marcy and I set up the course she’d scouted by duct taping squares of astroturf (to tee off from) and then marking “holes” to aim the balls into. It was an absolutely hilarious time. We got lots of strange looks but only a few comments, and no one called the police. Hooray!
  • Waving my hand through the water of Puget Sound to trigger bioluminescence. This is completely awesome. Too bad the water’s so cold. I can only imagine how phenomenal it would be to SWIM while glowing blue!
  • Attending a rock concert in hipster bar. I only recently learned what a hipster was! But this place apparently sold the right beer and attracted people with the right fashion sense. The highlight of the evening was a Japanese band called Mugen Hoso, which consisted of two too-cute Japanese guys in the middle of their “BIG BANG! BANG! BANG!” tour. They’d driven 40 hours from Austin, TX, to arrive 5 hours before this concert, but were buzzing with energy and played their hearts out. So charming, so rockin’, so cute!
  • Climbing up on a bench to escape a moshing crowd. At first I thought Mugen Hoso had inspired some massive brawl, but it turned out that the people were intentionally slamming into each other and apparently enjoying it. Beer quickly slicked the floor, and it got harder to pay attention to the band. Even though I had a great view from the bench, I had to be ready to catch and push back on random bodies that came flying at the bench. Headbanging I’d seen before, but this? Wow.
  • Picking blackberries and eating them with vanilla ice cream. Mundane for many, perhaps, but a marvelous treat for me :)
  • Attending a roller derby match. I didn’t know anything about roller derby, so was grateful to have an informed friend along! Basically, it’s two teams of super-athletic women racing to score points by passing the other team’s members around the rink. It’s quite a spectacle, with players decked out in fishnets and face paint, but what really steals the show is the amazing skating (on old-fashioned four-wheel skates, no less). Olympia has a world-class team, and they demolished their opponents from Cincinnati with a final score of 299 to 81! (Check out this picture from the match.)
  • Watching salmon prepare to head upstream, and seeing a “fish ladder” that helps them get past a dam. Wow, those salmon are huge! We also saw seals swimming around them ready to catch a meal, and blue herons winging all over — beautiful.
  • Cutting someone else’s hair. I got to use a comb and scissors, just like a pro! Marcy is a brave, brave woman.
  • Attending a party where I was the only one without a tattoo. Well, okay, I think Marcy is also tat-less, but we were definitely the only ones. Turns out that tattoos don’t keep people from wanting to play croquet, though!
  • Mutton Bustin’. Technically I didn’t actually get to see this, although we did call up some videos. Marcy and I met up with a high school friend of mine who talked about how her son had just won 3rd place in a Mutton Bustin’ competition at the fair. This is a sport in which small boys are put on sheep (yes, sheep), then the sheep is tickled and prodded into a frenzy, and then they are let out into a yard where the boy tries to cling to the sheep and not get bucked off. Wow!
  • Being in a comic strip. That’s right, one of Marcy’s friends who also golfed with us, Chelsea Baker, is an illustrator and comic artist. She created this summary of Urban Golf, and I ended up in it!

    That’s me with the hat and argyle sweater over my shoulders.

Now that’s an incredible, learning-filled weekend!

Train-based history of Oregon and Washington

Yesterday I had the pleasure of riding the Coast Starlight train north from Albany, OR, to Olympia, WA. As always, I was entranced by the stunning views, the vast comfortable ease of travel, and what interesting things there were to learn and see. From Portland north to Seattle, the train has volunteers from the National Park Service who sit in the observation car and offer interesting bits of history or explanations about what you’re seeing outside those huge picture windows. This is brilliant! I learned a variety of interesting tidbits:

  • Portland got its name as the result of a coin flip. The two founders, Asa Lovejoy and Francis Pettygrove, each wanted to name it after their favorite back-East city, respectively Boston and Portland (Maine). They flipped a coin and Pettygrove won. (Speaking of names, ever wonder how Oregon got its name? The wikipedia article on this is disappointingly inconclusive, but the various hypotheses are interesting.
  • A Columbia River drawbridge was open when we arrived, so we had to wait for it to finish letting some ship through. The Columbia has been dredged multiple times to permit the passage of deep-sea ships up it.
  • The Coast Starlight’s running speed is 75-79 mph. (It doesn’t feel that fast because it’s so smooth and quiet on the inside!) That speed limit is dictated not by the trains but by the track system, which was designed to accommodate the (much slower) freight trains. Apparently if the CS ran any faster, it would outpace the signaling system (e.g., the triggers prior to an intersection that sound the bells and lower the gates).
  • Wheat grown in Washington is soft/winter wheat, mainly used for noodles and doughnuts. 90% of it is shipped to the East. Wheat from Montana is harder (heartier?).
  • As a southbound train went by, full of grain cars, our guide commented that each train car holds 100 tons of grain; there are 110 cars in 1 train; and the contents of 6.5 trains fill 1 ocean carrier.
  • We passed several artificial mounds and hills as we passed through Washington, which are formed from clearing ash from the 1980 Mt. St. Helens eruption. Ash had to be scraped off of hundreds of miles of roads and tracks.

Now I’m in Olympia, where more things to learn await. :)

How I run

Have you ever watched yourself run? Beyond simple vanity, examining how your feet strike the ground can help determine whether you have the right support (and can also help pinpoint causes of foot, knee, and hip pain). Sole Sports, a shoe store in Arizona, has taken this to heart with their free Video Gait Analysis. My sister stopped in to see if she might learn something useful, and my mom and I tagged along.

We all ended up jogging on a treadmill while a small camera recorded us from behind from the knee down. It was fascinating to see a view that is otherwise physically impossible to achieve, and we did learn some things. My mom and I both run in a mostly neutral position, while my sister has some pronation. My mom and sister both run with their feet in parallel tracks, while I run in-line, with my toes slightly turned out. The Sole Sports guy said that both ways of running are common and neither one is better than the other.

The goal of the analysis, of course, from the store’s perspective is to recommend a particular shoe for you to purchase. My sister was recommended the “stability” shoe which helps compensate for pronation. After testing several options on the treadmill, she went home with a shoe that performed admirably the next morning during a run. She said that her knees felt much better than they had with her old shoes, which is great! Thumbs up for Sole Sports.

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