Jim Johnson’s Total Solar Eclipse of the Sun Experience

At about 1327 CDT on August 21, 2017 near Gordonsville TN, I stood less than 100 yards off of the center of the path of totality, waiting for the moon’s shadow as it raced across the earth’s surface, and I stood within that shadow for about two minutes and 39 seconds. A combination of many things put me in that time and place. Perhaps luck, skill, and drive were among them. Many have asked me to describe the experience, and my first words have included the word “beautiful”, and something like “words cannot describe. This article will be of few and inadequate words.

Astonishment is the single word that is probably most descriptive of my reaction. I had read a lot about eclipses, and I thought that I knew what to expect. Nonetheless, I was completely astonished at how quickly and how deeply the final darkness set in from the time that I could last see stark shadows on the ground, and then no shadow at all. The reappearance of light and shadows at the end of totality happened equally as fast.  I was astonished at how bright and how large the sun’s corona appeared, and equally astonished at how vastly black and empty the moon appeared at the center of the corona. Gazing upon the combined effect felt to me as if a hole had opened up in the fabric of the universe. I actually felt a moment of panic.

I did manage to see Venus and Jupiter. I looked for, but could not see Mars nor Mercury. I could see parts of the “360 degree sunset” anywhere that I had a clear view of the distant horizon.

I made an effort to observe a phenomena called earthshine, where sunlight falling on the earth’s surface is reflected up to the moon, and back to the earth again. As I said before, I was astonished at how utterly black the moon appeared at the center of the sun’s rather bright corona.

I tried to observe the approaching umbral shadow of the moon, but could only see indirect evidence of it as light changed in and on the distant clouds. I also tried to view shadow bands against a white shirt that I had dropped onto the ground – nothing there either. All in all, no big deal.

I did not think to try to observe prominences on the sun. This is understandable as I had just lost my mind.

I visually observed first contact, the first bite that the moon took out of the sun, through a filtered telescope. I took peeks at it off and on in this manner, and with eclipse shades for the 90 minutes from first contact to totality. I did not observe anything after third contact when the sun emerged from the other side of the moon’s disk.

I managed to see the diamond ring effect just prior to totality and just after totality. I did not see anything that I could identify as Baily’s Beads.

I was able to observe solar crescents resulting from the pinhole effect of leaves in a tree just prior to totality. I noticed that the quality of the light changed, and shadows appeared to sharpen. And certainly, I could feel the sun’s intensity drop from early in the partial phase of the eclipse.

I did not notice any animals, so no behavioral changes were noted.

Secondarily to the eclipse, I devised an automated method of taking some images prior to and during totality. I clicked a Start button, and did not have to fiddle with the camera/telescope until after the imaging run was complete. Some preliminary, pre-processed images follow below.

The first image is of the diamond ring that appears in the final seconds before totality. In addition to the brilliant diamond, there are some features of interest to note in this photo. All three regions of the sun’s atmosphere can be seen. The white area from the reddish area just above the diamond to the reddish area just below the diamond is the photosphere. This region of the atmosphere is closest to the sun’s surface, and the white light that we observe from the sun originates here. The chromosphere is the next highest region of the sun’s atmosphere. It can be seen in the two reddish areas previously mentioned. Also, at about 2:30 and 4:30, promeninces rising out of the chromosphere can be seen. And finally, everything else, and the bright parts of the other two images are the outer region of the corona, which is the main event for a total eclipse of the sun. A final, processed image will be available shortly.

My travel plan was to arrive at Louisville, KY on the day before the trip, assess the weather, and choose an observing location on the morning of the eclipse.  This reduced my risk of being locked into a location that would be clouded out on the day of the eclipse. Gordonsville TN was the location that I choose and drove to that morning. They skies had been crystal clear all day but cumulus clouds rolled in just as the moon’s disk began to cover the sun. Since there was enough clear skies between the clouds, and they were moving along at a pretty good clip, I felt confident that I would be able to get a glimpse of totality, if not see all of it. As it turned out, the sky became crystal clear again before totality arrived.

The entirety of the driving was arduous, and I put a lot of effort into planning for the trip. In short, it was well worth the effort, and I will put myself in the path of the moon’s shadow at every opportunity.  The next total eclipse of the sun occurs on April 8th, 2024, just a little over six years from now. I encourage everyone to plan to travel to the path of totality to see this astonishing event.

The Great American Eclipse - Diamond Ring
The Great American Eclipse – Diamond Ring

 

The Great American Eclipse - Corona
The Great American Eclipse – Solar Corona

 

The Great American Eclipse - Solar Corona
The Great American Eclipse – Solar Corona

Going after 2I/Borisov – Solar System’s Second Interstellar Visitor

Introduction

2I/Borisov is a comet that originated from beyond our solar system, and is presently passing though it. Once it leaves, it will never return. This only the second interstellar visitor that we humans have detected.

Borisov is not likely to be brighter than magnitude 15.5, it is a diffuse object, and will not appear any higher than about 30 degrees above the horizon from my location. These three factors suggest that this object might not be visible at the eyepiece of even my 12″ Meade. Still, though, to point my telescope at this object to capture a few photons would be really cool!

Technical challenges

In order to do photograph this comet, I have three really big technical challenges to overcome, and I will not have the luxury of a practice session before attempting a photo. First, I need an ultra-precise polar alignment so that my slews will land spot on the target, and so that my tracking will permit long exposures (10 minutes?) with minimal autoguiding. I have accomplished this with PoleMaster several times this year and within the last month, so this should not present a problem. Second, I need to be able to autoguide on a star to compensate for any residual errors remaining after I have obtained my best possible polar alignment. I have not done this in over a year, but I have opened the software, connected it to the guide camera and to the telescope mount, so this should not be a problem. And third, since 2I/Borisov has a significant angular velocity, I need to be able to obtain offsets from a star based upon the comet’s Ra and Dec rates. This is a very complex task that I have not tried heretofore. I have walked through the instructions, and I have connected the planetarium software to the guiding software.

Ideally I would test the last challenge – feeding cometary rates to the mount – but the only way that I can test is with a comet. Also, The conditions for imaging the comet are worsening as time passes, so I want to take advantage of the first opportunity. So, I will ultimately be testing on game day. At first I wasn’t sure if I could pull it off. I have worked hard on this problem, and I think it is going to work.

Things to do before going to the field

Just a few more things to get done. I have written a brief guide for obtaining and feeding cometary angular rate data to the mount, so I want to practice running through a couple of times to tweak it. I also want to set up all of the equipment that I will be using. Practice is always good, and I can think of no better way to get everything that I need in one place.

Closing thoughts

2I/Borisov is viewable in the wee morning hours from my northerly location. Looking ahead at the coming weather forecast over the next few days, December 5th appears to be my first opportunity to image this object, so I will be watching the weather closely. I have lots more work to do over the next few days. More to follow shortly.