As I write this it's just two days until the "Great American Solar Eclipse" as a lot of people are calling it. This is the first total solar eclipse that I've had a chance to see without having to travel significantly and I'm pretty stoked I can tell you!
First of all, let me just say that if Monday comes and at my very carefully scouted location just south of Columbia SC, right on the centerline of the Moon's shadow, I end up standing under a densely overcast sky only to have it go dark as night for 2 minutes and 31 seconds at 2:47 PM I think my head will explode! I've been thinking about and working on this for literally months and very intensely for the last few weeks so it will be a giant disappointment if that's what happens.
But let's assume we'll have a nice clear sky (or at least broken clouds fairly far apart) for the eclipse. What kinds of things are there to see in your two and half minutes?
Cover Up
From my chosen observing location the Moon starts to pass in front of the Sun at 1:12PM becoming completely eclipsed at 2:40 so you've got an hour and a half of watching the Moon slowly creep in and cover the Sun–oh the anticipation! During that time the Sun will get dimmer and and as you get well past 50% coverage you're going to notice that, while it's still obviously "daytime" the Sun's light is obviously diminished. It's widely reported that during the run-up to an eclipse the birds are fooled into thinking it's becoming evening ("What already??? Feel like I've only been up for a few hours!) and start singing their evening songs (Stairway to Heaven no doubt)!
Moon Shadow, Moon Shadow
As the moment of totality approaches the Moon's shadow is sweeping across the Earth at a speed determined by it's orbital velocity around the Earth combined with how it falls on the spherical Earth–faster at the edges, slower in the middle. At my location the speed of the Moon's shadow will be coming at me from the Northwest at about 1500 miles an hour. But here's the deal: you can actually see it! The perfect vantage point for this would be from an elevated location with a valley to the NW. You'd be able to see the seventy mile wide shadow coming at you at 1500 MPH from 20 or 30 miles away, almost as impressive as the eclipse! When the shadow 'hits' you that's the beginning of totality.
Starry Starry Day
One of the things that a lot of people don't consider is that since the Sun is completely covered by the Moon it's dark enough to actually see the planets and bright stars that are normally obscured by the Sun's glare. What you'll see will look something like this:
There are two planets close to and on opposite sides of the Sun: Mercury on the lower left and Mars on the upper right. These aren't particularly bright but should be easy enough to see if you know to look for them.
However the planets Venus and Jupiter are quite bright and should be blazing away. Venus is about 4 times farther away than Mars on that side (bright as a plane) and Jupiter is a little farther than that on the opposite side of the Sun and almost as bright. You'll start to be able to see Venus 15-30 minutes before totality; the other planets will start being visible 30 seconds prior to and after totality.
You may also notice a bight star close to the Sun/Moon on the upper left; that's Regulus the brightest star in the constellation of Leo. Ever wonder what they mean by "the Sun is in Leo"? Well there ya go! As you look around the darkened sky you should be able to see some of the other brightest stars like Sirius.
Have a Corona
Yes, I will be enjoying a fine cold beverage during all of this (after all it's midday in South Carolina in August!) but the 'corona' is the name we have for the Sun's outer atmosphere, invisible unless you can block the bright disc of the sun, like with the Moon!
In this photo you can clearly see the corona streaming away from the Sun at a million miles an hour; we call it the "solar wind' as it travels through space.
Bead Dazzled
You could possibly see what are called "Bailey's Beads" which are caused by the fact that the Moon's edges are not perfectly smooth nor is it perfectly round; there are all kinds of crater walls of varying heights with gaps in them which allow some very tiny bright spots to appear all around the edge of the eclipsed Sun.
Whether or not you see this phenomenon is determined by the apparent size of the Moon and how closely that matches the size of the Sun.
Diamond Ring
You can also potentially see a 'diamond ring' as the very last bit of the sun is covered up or first bet is exposed. This is visible in the Corona photo above. The bright spot at the upper right is the 'diamond' and the Moon/Sun is the ring, get it?
Taking Stock
Well that is a lot to do in two minutes and thirty seconds I know but it only takes a few seconds to notice these things and let's face it, as much trouble as it is to get yourself in the Moon's shadow like this it would be a shame to only note 1/4 of the stuff that's going on.
A lot of people have asked me what I'm doing for the eclipse and I've decided to put up four cameras, one telescope (with a camera looking through it and a camera riding on the mount) and a pair of binoculars on a stand with a filter on one eye.
The camera looking through the scope will be my CCD camera hooked up to my laptop computer and I'm planning on having it take a picture every 5 seconds throughout the entire 3 hour event. The Sun is a bit larger than the field of view for this camera but you should be able to see some good detail in sunspots should there be some that day.
Riding on the mount will be my still camera with a wide view which will be set to take a set of seven bracketed exposures (3 too dark and 3 too light) every time you press the shutter button. The camera is controllable by WiFi so I'll just repeatedly press the shutter button on the phone app as many times as I can while the Sun is totally eclipsed. I should get around 400 shots of the eclipse this way, I'm hoping to get one great shot out of it.
I'm going to have a GoPro Camera on some kind of tall tripod pointed towards the northwest, possibly in time lapse mode to see if I can capture the Moon's shadow approaching and get a wide angle shot of my setup and any other people who might be around.
Lastly I'm going to have a video camera running, probably also on the telescope mount to capture the sound as much as a video. It's totally possible I could find myself in a throng of people (which would be cool I think) and I've heard that the collective sound of a crowd as the Sun becomes completely eclipsed is absolutely electrifying! Well as a 'sound oriented' type of guy I have to give this a shot.
I'm also considering streaming this live on Facebook, would you watch?
Wish me luck and I'll post as much of this as I can deal with in the days following.
Bill