 |
| Texas is famous for a lot of things, including bluebonnets |
It seemed so, so far off, but, here we are in 2024 and I just got back from my second total solar eclipse that I watched with Caty and Scott. Yes, we invited Becca, but she declined and was able to see a pretty good partial from Oklahoma City.
In between, last year, Caty and I went to Nevada to a see an annular eclipse and Scott saw it in Texas.
 |
| 2023 annular eclipse, Great Basin National Park, Nevada |
In my earlier blog, I didn't explain a whole lot about eclipses, so let's dive in.
What is a Total Eclipse?
A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby obscuring the view of the Sun from a small part of Earth, totally or partially. In a total eclipse, the disk of the Sun is fully obscured by the Moon. In partial and annular eclipses, only part of the Sun is obscured. Unlike a lunar eclipse, which may be viewed from anywhere on the night side of Earth, a solar eclipse can only be viewed from a relatively small area of the world. As such, although total solar eclipses occur somewhere on Earth every 18 months on average, they recur at any given place only once every 360 to 410 years.
 |
| Straight line; Chart: timeanddate.com |
The Moon's orbital path around Earth is inclined at an angle of approximately 5° to the Earth's orbital plane around the Sun (the ecliptic). Without this slant, we would be able to see two eclipses per lunar month: solar at every New Moon and lunar at every Full Moon. But, that doesn't happen because to have a solar eclipse, the New Moon must be at or very close to one of the two points where the orbital planes meet, called lunar nodes. If the New Moon is not near a lunar node, it passes just above or just below the Sun as viewed from Earth.
 |
| This is how the nodes work; Chart: timeanddate.com |
On April 8, the New Moon was at a lunar node. But, that's not enough.
The Moon's path around Earth is elliptical, with one side of the orbit closer to Earth than the other. The point closest to Earth is called the perigee and the side farthest from Earth is known as the apogee. Earth's orbit around the Sun is also elliptical, with the Sun closest at perihelion, and farthest away at aphelion.
Earth's and the Moon's elliptical orbits mean that Earth's distance from the Sun and the Moon's distance from Earth varies throughout the year.
 |
| Fully covered |
It also means that from Earth, the Sun's and Moon's apparent sizes change during the year.
When the Moon is about 400 times closer to Earth than the Sun, the Moon's and Sun's apparent sizes roughly match, Total solar eclipses can only occur when the Moon is near perigee. This is the only time when the disk of the Moon is big enough to cover the entire disk of the Sun.
When that happens, the Moon's shadow creeps across the Sun, reducing it to a crescent (this is called the progression), slowly darkening the sky.
 |
| Just a few slices |
When the Sun is totally blotted out, the sky is dark, which allows you to see the corona: rays of light streaming out from the Sun. You can also see prominences: flares of flames exploding from the Sun's surface.
 |
| What you can see! |
As the relative positions of the Sun and Moon continue on their paths, the shadow pulls away and the crescent grows larger until the full Sun is revealed. This is the regression.
 |
| With eclipse glasses; Photo: Scott Stevens |
During both progression and regression, the Sun's full fury can be seen and you must protect both eyes and cameras from the intense light. We had several types of eclipse glasses and special filters for each lens.
During the total eclipse, none of the Sun's surface light is viewable, so you can remove glasses and filters and look at the corona with naked eyes.
 |
| The corona in full blaze |
When you photograph an eclipse, you can vary the exposures to get difference looks of the corona.
 |
| Nothing changed here except the camera settings and PhotoShop processing |
And, just before and just after totality, if you are fast you can see the "diamond ring," a burst of light that looks like, well, a diamond ring. I caught it both times.
 |
| I got better flare in 2017, left, and better focus in 2024 |
 |
| Scott got it coming in and Caty got a nice one going out |
 |
| Annular eclipse, 2023 |
An annular eclipse is similar, but because the Moon is not at perigee, the Moon only partially blocks the Sun, leaving a full viewable ring around it.
You can't take off the glasses for this because the visible Sun ring would burn your eyes.
The annular eclipse is cool, but nothing compared to a total.
During any total solar eclipse, totality lasts the longest near the center of the path, widthwise, and decreases toward the edge. The time in totality falls off slowly until you get close to the edge. Past the edge, you can see a partial eclipse, with only part of the Sun obscured and no chance for a corona.
 |
| Almost all of the U.S. could see some degree of eclipse; Chart: Celestron |
For both eclipses, we were right on the center of the totality.
 |
| More time to get the shot |
This year's eclipse had lots of pluses, making it even cooler than 2017 (plus, it was Scott's first total eclipse).
The 2024 eclipse had a longer time in totality than 2017. Back then, the maximum totality was 2 minutes and 42 seconds. This year's maximum was 4 minutes and 28 seconds in Mexico and just a few seconds shorter where we were.
The 2024 eclipse had a wider path than the 2017 one, making it more accessible to more people (plus it ran through much more populated areas).
 |
| Two very different paths; Chart: NASA |
This is because, as the Moon orbits Earth, its distance from our planet varies. During the 2017 total solar eclipse, the Moon was a little bit farther away from Earth than in 2024, making the shadow a bit smaller. In 2017, the path ranged from about 62 to 71 miles wide. In 2024, the path over North America was 108 to 122 miles wide.
 |
| Hot stuff! |
Immediately evident when the eclipse entered totality was a higher level of solar activity.
Every 11ish years, the Sun's magnetic field flips, causing a cycle of increasing then decreasing solar activity.
During solar minimum, there are fewer giant eruptions from the Sun, such as solar flares and coronal mass ejections.
But during solar maximum, the Sun becomes more active.
In 2017, the Sun was nearing solar minimum. The corona was more uniform and we could see only one major prominence and only when we looked at our photos. This year, the Sun is near solar maximum. The corona was more lopsided and there were numerous major prominences, visible to the naked eye.
 |
| 2017, left, and 2024, right |
The biggest one we could see was, according to NASA, the "size of several Earths."
 |
| Imagine a flare bigger than Earth! |
 |
| It just kept popping into my head |
Why Ennis?
Caty selected Ennis, Texas, as the best possible place because, as I mentioned, weather seemed more predictable than farther north and (a big AND) Ennis is famous for its spring bluebonnets (and other wildflowers, such as the very evident bright orange paintbrush flowers).
 |
| Caty loves her some bluebonnets! And, why not? |
Bluebonnets are the most beautiful aspect of Texas. And, despite that, we had never visited Ennis' Bluebonnet Trail. I will talk about the bluebonnets in my next post.
Ennis has a bluebonnet festival in late April and had added on to that with an eclipse festival of sorts.
 |
| A welcoming town obviously excited to be in the center of the action |
But, I do need to address weather. As the eclipse approached, weather forecasts kept getting worse and worse: rain, clouds and wind. Indeed, we drove through some horrendous wind (you know, the kind that topples trucks, sandblasts you with dust and requires an iron grip on the steering wheel to stay in your lane).
Then, when we got to Ennis, it was lovely: sunny with passing clouds and a light breeze.
 |
| Lookin' good! |
But, eclipse day dawned foggy and overcast.
When the eclipse started just after noon, we had full clouds. Rats!
 |
| Would everything be masked? |
But, as the Sun started eating the Moon, the clouds started to dissipate.
 |
| The progression through the clouds |
For totality, we had a clear sky except for one brief passing cloud that did nothing to dim the experience. And, it was a great experience.
 |
| We were afraid we'd miss the corona |
We had opted to watch from a field behind our hotel in Ennis.
Foreground didn't matter because the eclipse started just after noon, making the Sun so high in the sky that you can't capture foreground and have a big enough Sun image in your photos.
Being that high also made looking through the camera tricky (a stool made it easier).
Someday I'd like to see one early of late in the day, so the Sun would look bigger and there would be more color in the sky.
We ended up on the sidewalk behind the hotel next door and I actually set up in front of my car in the street because the pavement was more level and secure for a tripod.
 |
| Crescent-shaped shadows (caused by the progression) on "our" sidewalk |
A small group of people had gathered on lawn to watch and everything was blissfully uncrowded and peaceful.
 |
| Waiting for the eclipse; Photo: Scott Stevens |
Right before the eclipse started, a rather nasty woman came out from the Days Inn and demanded that everyone leave their field. It didn't affect us, but it was rude and uncalled for.
In a town that was inviting people to come to see the eclipse (and benefiting financially from that), this was oddly off-character for the town.
Shame on Day's Inn.
But that and some restaurants' inability to deal with crowds were the only issues.
Otherwise it was a lovely day.
And, even with all the predicted heavy traffic, we had no trouble driving back to Dallas so that Scott and Caty could fly home the next morning.
But, I'll talk what I did after that later.
In a town that was inviting people to come to see the eclipse (and benefiting financially from that), this was oddly off-character for the town. 
No comments:
Post a Comment