Thursday, August 17, 2017

Your memories of totality

If you talk to someone who has experienced a total solar eclipse, they'll tell you that it seemed to last just a few seconds. Some totalities are actually that short, but the effect happens no matter how long the totality is. Why is that? It's because the corona is so beautiful, so mesmerizing, that people tend to stare at it. The solution? Look at the corona, but also look at the other features of totality.

For more on this, see http://everythingintheuniverse.com/blog/sperlings-8-second-law-all-total-solar-eclipses-last-8-seconds

Make the most out of the experience!

Wednesday, August 16, 2017

Eclipse checklist: What to look for



The topic of this post is a checklist of what to look for if you are experiencing the eclipse. It’s primarily aimed at those who are in the path of totality, but some of this information can be used by people who will be experiencing a partial eclipse.

I’ll refer you to my earlier descriptive post on what happens during a total solar eclipse: http://eclipseaugust2017.blogspot.com/2016/05/what-happens-during-total-solar-eclipse_15.html

Also, of course, this assumes you know the eye safety rules. Before the eclipse begins, or during ANY part of the partial, you have to protect your eyes using proper methods and materials. But totality is COMPLETELY SAFE TO LOOK AT WITHOUT PROTECTION.

So, here is the checklist. These are in general order, but may not be exact. 

First Contact: you’ll see the silhouette of the Moon seem to take a bite out of one corner of the Sun

Projected images: ANYTHING with a small hole in it can be used to project an image of the eclipse onto the ground or other lightly colored surface. Turn your back to the Sun for this. Use a kitchen colander. A hat. Stand under a leafy tree and see dozens of eclipse images on the ground and walls! Be creative!

Light level drop: at some point, the light level will begin to drop. It’s really that the Sun’s glare is going away. Notice how the light level drop is slow and subtle at first, but picks up in intensity as the eclipse progresses. Also notice the coloration in the sky: it’s not the same as a normal sunset

Landscape coloration: how is the light level drop affecting the way the landscape appears?

Temperature drop: the temperature will begin to drop off, or at least stop rising

Strange shadows: the Sun will be a crescent: shadows of objects will look noticeably different than normal

Nature/ animal reactions: Look for flowers closing. See if animals seem to be doing strange things. If you’re not sure if the behavior is abnormal, make a mental note and ask a local later.

People reactions: during the early stages of the eclipse, most people will be only paying partial attention to the eclipse- conversations may be mostly about other things. But there will come a point when the eclipse is on EVERYONE’S mind.

Primal reactions: you know what’s happening- the Sun is being covered by the Moon and will return again- but people many years ago did not know that. As you approach totality, you’ll begin to understand why people would have felt so terrified back then.

Strange calmness: the air will feel very still and strange. This feeling increases in intensity as totality approaches

Other weather changes: is the wind picking up? Calming down?

Darkness building in the West: This is the shadow of the Moon, coming at you at about ½ mile per second (exact speed depends upon where you are) Can you actually see the motion of the shadow?

Sunset glow starting: look for a pink, orange or yellow glow starting to appear on the horizon

Rapid light level drop: at some point, the light (which is already dimmer) begins to drop with each passing second

Shadow bands: ripples of shadow running across the ground. They are rarely seen, and when they are, they are usually subtle. Use a lightly colored surface. Prominent displays are very rare.

Baily’s Beads: the thin crescent Sun breaks up into a string of beads- sunlight shining through valleys on the Moon.

Diamond Ring: the last 1 or 2 rays of sunlight before disappearing

TOTALITY!!!! It is SAFE to look without protection.

The Solar Corona: look for Coronal Streamers stretching several solar diameters into space. Look for intricate detail- loops, lines, strands. Look for brush-like features. The corona is generally white, but do you see any hints of color in it? What overall shape is the corona?

Prominences: reddish flares of hydrogen gas, at the edge of the Sun. You won’t see them move- so it will be like the freeze frame of a movie. Look for different shapes.

Disk of the Moon: is it really black? Many people describe it as a black hole in the sky. How does the color of the Moon compare to the sky around the eclipsed Sun?

Sky Coloration: is it deep blue? Purple?

360-degree sunset: all around the horizon, there is a sunset glow- light coming from areas outside of the shadow

Transition between sunset glow and darker colors above: is it abrupt? Gradual? Are there other colors in this area?

Stars and planets: Venus should be blazing high in the sky to the west of the Sun. You can spend a few seconds scanning the sky to see other stars but I wouldn’t spend too much time trying to find anything specific or identify them. Just get a general view.

Shadow motion: you may not be able to see it move in real time, but the shadow is shifted to the West as totality begins, more or less centered on you at mid-totality (maybe shifted a bit north or south, depending on how close to the centerline you are) then shifting to the East as totality gets closer to ending.

People reactions: how are people around you reacting? Cheering? Crying? Awed silence?

YOUR reaction: how do you feel?

Primal reaction: many years ago, people understood the patterns of weather. If it was cloudy and raining for several weeks, people did not fear that because they knew it was the rainy season and the Sun would return- like it did every year. But at a total solar eclipse, there is NOTHING visible during totality that would have reassured them that the Sun would return again. As far as they knew, the world would stay like that forever. Think about THAT during totality.

Animal reactions: are you hearing or seeing any strange behavior from animals during totality?

Natural changes: what is the wind doing now?

Temperature drop: it may drop between 5 and 20 degrees.

Brightening to the west: the edge of the shadow is approaching

Chromosphere: a thin red layer of hydrogen-alpha gas appears at the edge of the Sun

Diamond Ring: the first bright ray of sunlight coming back

GO BACK TO PROPER EYE PROTECTION

Everything basically plays out in reverse after this point, but you may be celebrating!

Realize that these changes don't even really begin until a large portion of the sun is covered, and that they are subtle at first. Then, they are noticeable but not dramatic. It's only shortly before totality that things become really dramatic. That's one of the many incredible things about totality- it takes a while for things to become very noticeable, but when they do happen, it's a big rush!

Happy (and safe) viewing!

Saturday, August 12, 2017

What to bring to the observing site



When you're at the eclipse site, it's a good idea to be prepared, so that you can make the most of the eclipse experience.
Here is a list of suggested things to bring:
Proper eye safety viewers (see my other posts about this) (remember that totality is safe to look at (but ONLY that phase, and ONLY when the Sun is completely blocked out.))
Something with lots of small holes in it (kitchen colander, for example)- you can turn your back to the Sun and project dozens of eclipse images onto the ground
Sweater or jacket (the temperature drops leading into totality)
Hat
Pencil and notebook (for sketches of the eclipse, and writing down your feelings during and after)
Bug Spray (if there’s a lot of equipment around, be careful where you spray it.
Sunscreen
Food/ drinks- make sure you stay hydrated! Also, you may or may not be able to eat lunch at the observing site. At the very least, bring good snacks (not junk food) to eat so that you’re not hungry as totality approaches.
Other things to do. You’ll likely be on site before the eclipse begins. From then, and even during the early stages of the partial eclipse, the pace may seem rather slow. Bring a book to read, go for a walk, play a game, throw a ball around (if there’s not too much equipment around), go swimming- or just chat with others there. You’re about to share an incredible experience together!
Chairs and/or tables
Umbrellas (for shade!- hopefully you won’t need them for other reasons!)
Checklist of what to look for (there’s A LOT!)- I’ll post one on this blog soon.
Camera- you can take pictures of the eclipse if you want (make sure you use proper protection during the partial phases)- don’t spend too much time taking pictures during totality. You can use the camera to document your activities and family/friends who are with you on that day. More tips on eclipse photography on a later post.
Audio recorder (or a video camera)- you’ll want to make sure that you record your audio reactions to totality. See the other eclipse videos on this blog for examples of that.
Extra batteries and memory cards
Medicine/Pain reliever: A headache, stomachache or muscle aches can come up at any time. Be prepared for that possibility.
Toilet Paper- better to have it, and not use it, then the other way around!
Electrical tape, or anything dark- to cover the flash of the cameras around you. People may not remember to turn their flashes off, or know how to do it.
Some other links on the same topic:
Feel free to comment below on anything that I missed. Happy viewing!