You can derive them by working out the inertial rate of change of the moment of inertia tensor in the body frame. The equations you want are called the Euler equations. Check out photojourneys.ca for their amazing photography! If you’ve seen the video, you know what I did. I wound up watching videos on FortNine.įortNine has hundreds of videos but one, as if inspired by the universe, set me on a new path. The universe would tell me what to do.Īnd the universe did know what to do. I’d started with a Canadian ( Michael and his charming dog Esme) driving an Argo (made in Ontario), through Urals (made in Russia), test drove several Polaris (made in Minnesota), almost lit on a Rokon (made in New Hampshire) until I fell on the ice, and then had nightmares over my final decision to finance a Can Am (made in Ontario). Also, it felt like somehow this had to do with Canada. I’d given up all hope of buying anything like/near to/related to/of a kind to an ATV. In mourning for my dog, I sought solace in the simple joy of learning new things in this case geography. I mean, who would look for sand dunes that far north? Who can fail to be amazed by our friends to the north? Those clever buggers squeezed a piece of Morocco into a spare section of the frozen North. Walking on giant dune, William Dune Field, Athabasca Sand Dunes, Saskatchewan The retreating glaciers trapped behind them a small cold piece of something that you’d associate with camels. Milankovitch and his space math it’s due to the secondary effect of ice sheets retreating (which definitely had something to do with space math!). This isn’t directly caused by our Serbian braniac friend Mr. These are photos of the Athabasca Sand Dunes of Canada. Well what have we here? The universe never fails to amaze. We were too busy having every living thing utterly obliterated by massive unending sheets of ice. Of course, I live in Northern North America, none of that shit went down in my area. I had a desire to see the Sahara… to touch the Earth in a place that’s gone from Steppe to Death. A desert that bloomed out of nowhere and kicked the shit out of whatever humans inhabited the region. With my dog dead and my heart set on sandy beaches, I thought of the Sahara. (Note: I mentioned this whole Milankovitch thing last fall.) The drier portion of what we now call the Sahara desert was steppe:ĭue to orbital eccentricities it turned to dunes This is the Sahara right now:Ĭompare those photos. Roughly 6,000 years ago about half of what we call the Sahara desert was savanna: This is cute and all, but Milankovitch Cycles cause a side effect that most folks don’t know. If you’re steeped in modern eco-think you might have to let this one settle a bit we’re still in the ice ages. Long before Al Gore roamed the Earth, Milutin Milankovic worked out that eccentricities in the earth’s orbit may have something to do with cycles of ice ages. Remember my last snowflake warning? Well here’s another one. If you’ve been steeped in a modern college and think driving an SUV in August kills penguins in January… you may want to sit down for this next part ’cause this is going to hurt your delicate noggin.Ībout a hundred years ago. OK fine, so what? Well if a few degrees of tilt, staying exactly constant in the scale of years and decades is the reason my lakes are frozen now and I’ll be swatting mosquitoes in a few weeks… what about variation in the tilt over centuries.Įnter Milankovitch Cycles. What I didn’t know was that the tilt has a periodicity. Think about it a couple degrees of tilt is why I hit -40 in winter and 100 degrees in summer… and never the opposite. Unless you went to college for something that’ll never merit your student loan bills, you probably did too. He certainly made clever arrangements to provide North American deciduous trees with a reason to go out in a yearly blaze of glory. Then again the tilt, as we all know (or should know) is the root of our seasons. If I welded a Subaru axle that badly, the damn thing would blow up. The axial tilt (Earth’s obliquity) is somewhere around 23 degrees. It would make sense that the earth’s rotation be exactly perpendicular to the plane of its orbit. All things that spin, rotate about their axis. So here goes the Earth hangs in the void, spinning. If I missed something significant, tell me in the comments. As I understand it, I’m more or less telling the truth. I’m going to oversimplify here because I’m a dumbass blogger trying to tell a story and not an astrophysicist. Time would pass and I would recover, but for a while I just held on and let the planet rotate. I couldn’t afford even a tiny bit of worldly concerns. I put all thoughts of buying anything out of my head. My dog died and I lost all sense of time and space, proportion or reason.
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