Saturday, March 22, 2014

Then, I saw the light

In the words of my home town’s most famous son, Dylan Thomas, “To begin at the beginning”:

If like I, you have a desk calendar, you may have noticed this year (2014 on Thursday March 20th that these words appear in the box for that day: ‘First Day of Spring’.

[Note: Punxatwney Phil had (yet again) predicted ‘6 more weeks of winter’. Of course, by ‘winter’, he meant ‘winter-like weather’ – but there were actually 6 weeks and 4 days from Groundhog Day (February 2nd) until March 20th.  - so he was not quite chronologically correct!  Never trust a rodent]     

But, I have digressed (a little) – it is one of my many talents.

"First day of Spring - that means the Spring (or Vernal) Equinox, right?" I said to myself. [One can sometimes avoid confrontation that way – just talking to oneself - but not always!] ‘Equinox’, eh? That suggests that on that date, there will be 12 hours of daylight and 12 hours of darkness – ‘equi’ means 'equal' and ‘nox’ means ‘night’, see? I had this great idea that I would take a photograph of the sunrise and of the sunset, record the time(s) of day and also note the compass direction of each of the day’s events. But first, I should ‘consult the charts for St. Louis’. That is when my world became a little unglued and I contemplated seeking a refund on my calendar purchase.  

It seems that the charts would indicate that I had missed the ‘Equinox’ by a couple of days. "How could that be?" an inquisitive person may ask – perhaps not you, but an inquisitive person may. 

Look here

                                                     Source: Sunrise/set, Time zones and more

Did you see that a 9 minute (plus the obvious 12 hour) differential between sunrise at 7:04 am and sunset at 7:13 pm. The date on which the differential is closest to ‘zero’ (7:09 am and 7:10 pm) is March 17th. Yes – just as I thought, the blydi leprachauns had something to do with it!  Undeterred, I recalled someone saying (something akin to) "A compass will always keep you straight". Well, knowing that other adage "The sun always rises in the East and sets (British Empire excepted) in the West", I expected to see – for March 20th – an azimuth of 90 degrees for sunrise and one of 270 degrees for sunset. I’ll bet you would have, too. LO and Behold (leprechaun twins, I believe, intervened again), see what that chart says – NOT on March 20th (it shows 89 degrees and 271 degrees) - but on March 19th - but don’t be blaming that on St Joseph - he had enough trouble getting to Bethlehem in time for Christmas!    

To more practical matters: I was unable (from my house) to photograph the exact location of the either the sunrise or the sunset – some louts had decided to build a lot of other houses in the subdivision (for the folks in the UK, read ‘Estate’ for ‘Subdivision’) so that my view is somewhat obstructed. For that same reason, I was unable to get a precise azimuth reading with my iPhone. Now, I have many photos of spectacular sunrise and sunset scenes (from my back deck for the former and from my front porch for the latter) that I will be glad to share with you. Just send a request written on a $5 bill or even a £5 note to ‘Swansea Jack’, 2 . . . [well, just Google NSA for my mailing address]

Remember that ‘. . . rises in the East, sets in the West’ thing?  Don’t believe it. Here is a photo of a sunrise I took in mid December - looking to the West!

                                                Note the moon is also visible in the upper left

Let me refer back to those danged charts for a moment. It occurred to me (one late January morning as I paced the corridor of a nearby hospital while my infant grandson was being monitored for pneumonia - he recovered fine, thank you) that ‘sunrise’, and of ‘sunset’, are (pun intended) in the eye of the beholder. I’ll provide a couple of links here shortly that will explain it better than I could.

You all know that as the sun is 93 million miles away (give or take a few hundred thousand miles any week) and with the speed of light being what it is, it takes 8 minutes for the light to travel from ‘up by there’ to ‘down by ‘ere’ (as they say in Wales). Not only that, but, you’ll notice in this next series of photographs that it takes more 9 or 10 minutes for the sun to get out of bed! I mean, it poked its head out over the blanket at 7:09 am and still had not bared its entire rump by 7:18 am. And therein lies the reason why those charts are they way they are. It’s all in the definition of ‘sunrise’ and ‘sunset’, you see.

                                                                Peek-a-boo at 7:09 am


                                                                  then a little yawn at 7:12 am 

                                                                  half-way up at 7:15 am

                          this is all of his rump I could 'bare' - before I almost went blind - at 7:18 am

Best explained here ‘Equinox 101’

More than you may wish to know can also be found here: Wikipedia on Equinox

One parting practical matter: If you are (at least, at my latitude) wanting to know when sunset will be on a particular evening, perhaps watching your child’s ballgame, here is a rule of thumb (pun intended). Just fully extend your arm(s) in the direction of the sun, palm(s) facing you; sight your hand(s) so that the top of the sun just peeks over the top of your (uppermost) palm and count the number of fingers down to where the horizon appears. Multiply ‘fingers times 8’and that is how many minutes until the sun will completely set below the horizon.

If any of this technical stuff has still left you in the dark, good! Maybe you’ll have questions and will comment on this blog. Whether you do or not (have questions), please share it with others – that they too may see the light!        

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