Almost 6 months ago to the day, I did a post called “Dark Week”, where I talked about the Winter Solstice, hours of daylight and sun angles. (A couple days later I followed up with a post explaining changes in azimuth between the solstices.) In that post, I suggested marking your calendar for this Saturday or Sunday to check out one or more aspects of the Solstice- the length of the day, the sun angle at noon, and/or the azimuth at sunrise/sunset.
Note: Yes, I recycled some of the graphics from that post for this post. Hey, I spent enough time doing them, I can damn well re-use them if I want…
It seems remarkable that 6 months flew by so fast. Each winter when you think about the coming year, you always think about all the time you’ll have and all the things you’ll do, and then before you know it, the time’s gone by and you’re setting your sights on the next year, and all the things you’re sure to get done then…
All About My Dentist
Tangent: The passage of time is foremost on my mind right now because yesterday I went to the dentist. I’ve been seeing the same dentist twice a year for nearly a decade. (pic right = actual photo of my dentist’s office, from his website. I think the lady in the photo is a model; I’ve never seen her, and the usual receptionist is about 40 years older…) Because I see my dentist only at long intervals, we have a weird relationship. We’ve spent maybe 6 or 7 hours together total, but it’s been spread out over a decade. Our relationship is kind of like one of those science fiction stories where people meet again after years-long interstellar journeys where, due to the effects of time-dilation at near-lightspeed travel, only a short time has passed for the travelers, but back on Earth everything’s different. Over the course of our basically single, 6-hour conversation, I’ve changed jobs once, presidents twice, had 3 children, and broken and mended my back.
Nested Tangent: Since I am going to pick on my dentist in a just a moment, I should say that both he and his hygienist are outstanding. This guy gives a novocain shot so smoothly you would not believe it. If you’re local and looking for a dentist in the Salt Lake Valley, let me know. He and his staff provide outstanding, high-quality service.
All About Pizza And Stoners
Speaking of customer service, this is a good opening for me to talk about something else that’s top of mind for me right now: Legalization of Drugs.
As you no doubt are aware, the whole issue of the “War on Drugs” and possible legalization of drugs is a big topic in the US right now. And for many years there have been a number of people who have proclaimed the War on Drugs a failure, having led to record incarceration rates and the creation of violent cartels, while failing to effectively curb drug addiction and dependency.
Now I should say that on the whole I am at least moderately sympathetic to these arguments. As long-time readers can probably ascertain, I tend towards liberal end of the political spectrum, usually vote for Democrats, and am supportive of things like wilderness protection, universal healthcare, and true, non-xenophobic, immigration reform.
And, if we’re going to be completely honest here, in my younger/college years, I did on a number of occasions, smoke my share of marijuana, and- I will confess here and now- enjoyed doing so thoroughly.
So you might think that I would be favorably inclined toward the legalization of (at least some) drugs, and yet at a gut level, I’m not. I’ve sort of half-wondered why this is, and last night, when our dinner was delivered, it suddenly dawned on me: Pizza.
Awesome Wife and I have a favorite local pizza place. They make great, high-quality and creative pizzas, deliver to our neighborhood*, and generally manage to find our house. But at least 50% of the time, the order is screwed up, and the pizza is made wrong.
*Unlike another well-known Pizza Place- let’s call it “The Pie”- who refuses to deliver to any address East of Foothill Blvd (we are 2 blocks past the limit) having determined everything East of this thoroughfare to be “the canyons.” Those guys are total geogratards.
We’ve discussed at length why this is so often the case with our orders, and have come to the firm conclusion- supported by numerous interactions with the employees of this establishment- that the majority of their staff is stoned the majority of the time. And this, right here, is what lies at the heart of my resistance to liberalization of US drug laws- the certain knowledge that if drugs are legalized, I will never ever get a pizza made right again.
Much of our continuing conversation has revolved around our common interest in biking. In years past, my dentist- let’s call him “Bill”, was also an avid cyclist. (pic right = actual photo of my dentist. I am telling you, he is awesome- best dentist I’ve ever had.) Like so many 40-something former cyclists, Bill doesn’t ride much anymore, and through our entire, decade-long single conversation, he has been talking about buying a new bike. Seriously, it’s been 10 years, and he’s still procrastinating over buying a new bike. Every visit he asks me my opinion about various brands and such, etc. Finally this time I just said, “Bill! It doesn’t matter. Any bike you buy today is going to be infinitely better than whatever circa-1980-elliptical-ringed-rusty piece of crap that’s sitting in your garage. We’ve been talking about this for a decade- just go buy a bike already!”
Nested Tangent For My Coworkers: Yes, I know that at least a half-dozen of you regularly read this blog (though by and large you are all too chickenshit to ever comment.) Anyway, you know what? There’s a guy in our office with whom I’ve been having the exact same, “I’m-gonna-buy-a-bike” conversation for 7 years. 7 years! Hint: he works on the 4th floor.
I keep hoping that my dentist will have the same kind of 40-something realization that I did a couple years back, shortly before I started this project: I’m 40-something. I’m a [dentist/salesman/whatever-the-hell-it-is-I-do]. I’ll never be an astronaut or rock star or Secretary-General. This, right here, is my life, and instead of just striving and hoping and procrastinating and thinking “gee, maybe someday…” all the time, I’m going to start living it.
Part Of The Post Where I Get To The Point Already
So yeah, the solstice. That’s something you can easily blow off every year, and plan on checking it out the next year, but then one day you’ll be on your death-bed and you’ll be like, “Oh shit, I never really checked out the solstice…” Think about it- you live on this giant, tilted spinning ball that is whipping around and around this giant star at a ripping 66,000 mph. You may think, well I can’t see it because I’m not an astronaut, but you can see it- you just have to look up.
At around 1:30PM Saturday and Sunday in Salt Lake, the sun will be up at an astounding 72 degrees in the sky. We don’t look up at the noon-sun much (and we certainly shouldn’t look directly at it) but if you check it out, you’ll be startled with just how darn high* it is. And if you look around you at noon, check out the shadows- they’re teeny!
*Almost as high as the guy working the phones at Wasatch Pizza.
Even cooler than the sun’s up-down angle, check out it’s “side-to-side” angle, by which I mean the path it travels around the sky. Between sunrise and sunset, the solstice sun in Salt Lake will cover an astounding 244 degrees of the total horizon. (I explained how this works in this post, and won’t repeat it here, seeing as I spent too much time already going on about my dentist and stoner-pizza-guys.)
Although the noontime shadows may be teensy, if you pay attention to early morning and late afternoon shadows around your home or office, you’ll notice light and shade in places you rarely see them the rest of the year (including sunshine on the North side of your house!)
Monday the days will begin to get a little shorter. But interestingly, although the sunrises will start to get a bit later each day, the sunsets will still keep getting later for about another week. How can this be?
This Part Is Not Really That Complicated But Is Super-Hard To Explain
Because the Solar Day is longer at the solstices than it is at the equinoxes. The Solar Day is the time from one Solar Noon to the next, and this time varies slightly over the course of the year. Remember, each day, the Earth travels ~1/365th of its path around the Sun. And because the Earth orbits the sun in the same direction as it rotates (counterclockwise) this orbital travel adds a little teeny bit of time to each solar day. From the standpoint of a non-rotating Earth, the Sun is creeping gradually East; from the standpoint of an Eastward-spinning Earth, it has to spin slightly more than a full rotation to “catch” the sun at noon each day. Our calendar of course is a solar calendar, and so accounts for this daily “catch-up”, which takes up about 4 minutes per day.
Side Note: A purely rotational day that ignores the position of the Sun is called a Sidereal Day. A Sidereal Day is roughly 4 minutes shorter than a Solar Day. Who cares about sidereal days? Astronomers, who want to know at what time which stars will be where…
OK This Is The Hard Part
But that’s 4 minutes on average; more time is added to the Solar Day at the solstices than at the equinoxes because the Sun changes its position relative to any given point on the Earth’s surface more each day around the Solstice than it does around the Equinox. The reason for this is the Earth’s axial tilt. At or near the solstices, the rotation of any point of the Earth’s surface at noon is pretty much parallel to the Earth’s orbital plane around the Sun, making the noontime change in relative Sun position effectively due East. But at or near the equinoxes, the rotation of any point of the Earth’s surface at noon is at around a 23.5 degree angle to the Earth’s orbital plan around the Sun, making the daily change in relative noon position is effectively Southeast (Fall) or Northeast (Spring.)
This greater effective change makes the Solar Day (which again, is Solar Noon to Solar Noon) a titch longer, because a bit more “catch-up” is required, causing our Average-Solar-Day calendar to get just a bit ahead of itself around the Solstice, resulting in a slightly later sunset. Closer to the Equinox, the calendar “falls behind” a little bit in relation to the then shorter Solar Days, and over the course of the year it all averages out. Get it?
There’s a second factor at work, and that’s the elliptical nature of the Earth’s orbit. Aphelion*- when the Earth is closest to the Sun and traveling fastest- is around January 4 (close to the Winter Solstice) and perihelion- when the Earth is furthest from the Sun and traveling slowest- is around July 4 (close to the Summer Solstice.) But the axial tilt accounts for the vast majority of variation in Solar Day length.
*I explained aphelion and perihelion in this post.
So this next week- the post-Solstice week- is probably the best week of the year to do stuff after work, whether it’s bike, hike, run, play in the yard with the kids, or just smoke pot and deliver pizzas.
Happy Solstice everybody!
Final Serious Note: In some other parts of the world- mainly northerly places, like Scandinavian countries- the Solstice is a big holiday. I think that’s really cool, and I wish it were a big holiday here as well. But here in the US, there’s an even cooler holiday that we should all be celebrating in a really big way, and it’s today, June 19th. It’s Juneteenth, a holiday celebrating the passage of the 13th amendment and the emancipation of the slaves.
The 13th amendment didn’t make everything right of course; African-Americans continued to get (and to a certain extent still do get) a shitty deal in this country for at least a century more. But the single best, coolest, most progressive thing this country ever did was abolish slavery. That’s something every American should be proud of, and a pretty great reason for a holiday. Unfortunately it doesn’t get the recognition it deserves*, but that doesn’t stop you from celebrating it, and maybe telling your kids why it’s so cool.
*Except in Texas. In my real life I have, many times, made fun of Texas, for everything from its kooky anti-science politics to its dismal zoning practices. But Texas is the one state which celebrates Juneteenth as a full state holiday (though several other states recognize it in varying, lesser degrees.) Way to go, Texas.