Wednesday, September 30, 2020

Nature in the City, Part II: Chicagohenge, 2020

 


After visiting my mother one day last week after work, I hopped aboard a bus which turned west on Randolph Street and this is what I saw. 

I'm not sure when the term "Chicagohenge" was coined, but it describes the phenomenon of the sun rising and setting close to the horizon at the vanishing point of the city's east-west streets during the vernal and autumnal equinoxes. It's not unique to, but is particularly spectacular in Chicago because of the canyon effect created by the skyscrapers in Chicago's Loop and the fact that the direction of our streets correspond almost directly to the cardinal points of a compass, unlike say the streets of Manhattan. 

The "henge" part as you can probably guess, is after Stonehenge, the prehistoric stone circle in Great Britain whose arrangement was very likely designed to line up with another significant astronomical moment of the year, Summer Solstice, the longest day of the year and the first day of summer. On this day in the Northern Hemisphere, the sun reaches its highest point in the sky before it begins its gradual descent which culminates with the Winter Solstice, the shortest day of the year roughly on the 21st of December, when the cycle begins anew. To the ancients, the reversal of the sun's downward slide became noticeable around December 25th, which became a day of great rejoicing to people who had no practical explanation for the motions of celestial objects, other than the will of the Gods. This day conveniently morphed into the day when much of Christendom celebrates the birth of Jesus. Credit for that goes to the Roman Emperor Constantine who in the process of converting his empire from paganism to Christianity, he likewise converted the day of celebration devoted to the figurative re-birth of the Sun into the day celebrating the literal birth of the Son. 

Smack-dab between the two solstices, the equinoxes are the two moments of the year marking respectively the beginning of spring and autumn, when the sun appears directly above the earth's equator. Because of the tilt of the earth's axis combined with the planet's continuous revolution about the sun, the solstices and equinoxes are moments which can be measured  to the second. This year, autumnal equinox occurred at 8:31 AM CDT on September 22, about 10 hours after this photograph was made. Had the setting of the sun in Chicago occurred precisely at the moment of the equinox, the sun would have appeared right on the horizon. Well not exactly because of the effect of refraction (bending) of light which makes the rising and setting sun and other celestial objects appear to be not where they actually are, but for the sake of argument, let's just assume that statement is true. 

The change of seasons is important to us modern day city slickers primarily because it marks the time when we change our wardrobe. Obviously the seasons are far more important to people who make their living off the land such as farmers. In this part of the world, it's harvest time and another astronomical event has for millennia, serendipitously aided farmers during this busy time for them. That event is Harvest Moon, which is the first full moon after the autumnal equinox. During Harvest Moon which will take place tomorrow, Thursday, October 1st, the particular relationship between the relative angles of the sun and the moon means that the lag time between moonrise from day to day is less than usual, resulting in the moon rising for several days, very close to the time of sunset. This provides extra illumination and is a boon to framers, giving them extra light to reap their harvest after the sun goes down. 

As an architectural photographer for many years, the significance of the equinoxes for me is that between them, the sun spends some of its time in the northern hemisphere, meaning that if I want to photograph a north facing facade of a building illuminated by the sun,  I can only do it in the time after sunrise or before sunset between roughly March 22 and September 20. The picture above marks the last day until next March when the sun will be visible between the tall buildings in the east-west streets of Chicago's Loop.

It was dumb luck, literally being at the right place at the right time, that allowed me to witness Chicagohenge first hand. I noticed dozens of photographers with serious gear snapping away as the sun made its last appearance above Randolph Street for six months.  

Strangely enough, my being aboard the bus gave me a slightly better vantage than the more prepared photographers as I was in the middle of the street and several feet higher than they were.

Life isn't always fair as they say and sometimes it's better to be lucky than good. At least it made up for missing that damn tornado lat month. 




Monday, September 28, 2020

Nature in the City, Part I: Tornado!

Living in the city, one can easily forget that no matter how much we think we are in control of our destinies, we all live under the forces of nature. Here are two posts about recent close encounters with Mother Nature, one terrifying, the other exhilarating. 

Chicago is one of those places that usually stays clear of nature's wrath. We're not near the ocean so we're spared the threat of hurricanes. Even though we are in the vicinity of a major fault line, The New Madrid Fault, the few earthquakes we get are generally too weak to notice. I slept through a recent quake and probably the most severe one in my life took place while I was riding the subway so while many friends felt the tremor, all I could feel was the normal vibrations of the train. 

Poor California not only has earthquakes to deal with but extreme draught conditions make much of that state vulnerable to wild fires such as those which are ravaging the Golden State as we speak. And the Gulf Coast constantly has to be on notice this time of year, hurricane season.

One thing we do get in this part of the country are tornadoes. I spent much of my childhood in fear of them, often being awoken in the middle of the night by air raid sirens which doubled as tornado warnings whenever a twister was spotted nearby, Fortunately we were always spared their wrath because those terrifying and unpredictable storms hardly ever make their way into the city and when they do their path of destruction is narrow. I have no idea why tornadoes typically avoid cities. My guess is that it's simply a matter of the luck of the draw, cities take up only a small part of the entire land mass of the country so the chances of a city being hit by a tornado is far less than everywhere else that is not a city. But that doesn't explain why some places seem to get more than their share of them, Plainfield, Illinois, a distant suburb of Chicago being an example.  

Anyway, our luck ran out last month when a tornado ripped through our neighborhood. Not only that, the storm's path ran directly along Jarvis, the street that dead ends into our building, then continues east to the lake. 

That morning I was a little excited because they predicted severe storms were heading our way. I guess I was just looking forward to a little something to break the monotony of quarantine. Besides I like storms, that is to say the ones we usually get in this area which involve thunder and lightning, a lot of rain, and this being Chicago, some wind. The storms we usually get are seldom accompanied by any destruction worth noting. 

I had to do some grocery shopping so I headed to the store earlier than I normally would have in hopes of beating the storm. As I headed back to my car with the groceries the sky looked ominous. The phone rang and I could see it was my daughter calling. As soon as I answered, a downpour started. Then came a sudden gust of wind. I couldn't hear her and as I was getting drenched and the wind was blowing everything all over the place,  I told her I'd call her back. At that point I was a little annoyed as I assumed she was calling to ask me to get her something from the store which I had just left. 

What I was experiencing, unpleasant as it was, didn't seem to me at all unusual. After I got in the car, I called my daughter back. She was frantic. "Get inside immediately" she told me. Foolishly I asked her why. It took several interrupted telephone conversations to put the pieces together, 

It turned out that she, my wife and my son, along with our cat, had left the apartment and were in the lobby of our building with several of our neighbors. Before departing, they saw trees bending in ways they shouldn't, small objects swirling about in a large circle, and a sickly green color in the sky. The whole nine yards.

"Holy shit..." I thought to myself, "...a tornado". By the time my daughter got a hold of me, the worst of it was over for them, they were just worried about me. They didn't need to because even though I was only a half mile away to the west, the twister was headed east toward the lake.  

Our building, a massive late 1920's luxury apartment building was unscathed by the storm, as were most of the buildings in our neighborhood. As you can see by the photograph, most of the damage was suffered to cars parked underneath trees that were uprooted by the storm. 

My first struggle was trying to get home as several streets were completely blocked by the fallen trees. But as I said, the path of destruction with these beasts is usually pretty narrow, and once I got back on the major through street, I was able to find alternate streets that were untouched. 

The other struggle not too surprisingly is that our electricity went out. The electric company told us we could expect to be without power for about five days. So much for most of the food I had just bought. 

Fortunately it didn't come to that and in the middle of our second dark night while we were all fast asleep, all the lights came on. 

Surveying the damage in the subsequent days, sure enough, street after street all the uprooted trees and squashed cars were within a swath probably no wider than the length of a football field. 

Given all the damage, it's a blessing that there were no serious injuries. Just lots of of survival stories which no doubt will get more and more harrowing as time goes on. 

Except for me that is as once again, I completely missed it.