How to view the solar eclipse with maximum safety and awe.

Should you take a photograph? Can you use binoculars? We've got answers. Plus, why this eclipse has special meaning for eclipse scientists and enthusiasts.

Substack AI.

On Monday, April 8th, the United States will experience a total eclipse of the sun. I’m hoping to view my first total eclipse! If you are in the pathway of totality—that is, the zone where the moon will be entirely blocking the sun for between 2 and 3 minutes—you should try to view it. Today’s newsletter is all about seeing an eclipse safely. Plus amazing tips from an experienced eclipse chaser/researcher!

Let’s break this up into three parts.

1. Can I see the eclipse from where I am?

Check out this map. It shows you the path of totality, and precise timings.

Keep in mind that the map uses Universal Time, which is +4 hours ahead of Eastern, +5 ahead of Central, +6 ahead of Mountain, and +7 ahead of Pacific time. You can check your time zone here.

If you’re wondering about the weather, here’s a link.

2. How can I safely view the eclipse?

Viewing a partial eclipse is dangerous. It can cause “solar retinopathy,” which can lead to permanent and significant damage. To look at a partial eclipse, you must wear protective lenses that are up to the task. Here’s a link to NASA’s site on this.

If you want more information, here is a link to a definitive resource from the American Astronomical Society. To be clear, here is a simple diagram about when you must use protective glasses (or a “filter”) and when not to:

Source: AAS.

During the few minutes of complete totality (again, here’s a map to know if you’ll be in that zone), not only is it safe to look at the eclipse with your naked eye, if you try to look at it using eclipse glasses, you’ll see nothing. Looking at a total eclipse directly is, apparently, life changing. That’s according to research, and, also, solar physicist Dr. Dan Seaton. Dan has seen four of these, and countless partial eclipses. (He also happens to be one of my closest friends from college.)

3. Tips for enjoying totality.

I spoke to Dan, an accomplished solar physicist who studies the corona during eclipses, about maximizing the experience.

Here are some tips and edited quotes from our texts.

1. Get as close to the center of the path as you can. The closer you are to the center of the path, the longer totality lasts. Avoid setting up at the edge of the band of totality (say, around 1 kilometer/0.6 miles). “There is a high degree of uncertainty about the edge of the eclipse path because we don’t actually know quite how big the Sun is, and the moon has mountains and valleys on its edge that could let a bit of light through. So don’t [set up] right at the edge of the path. Get as close to center as reasonable.” (Sidebar: I love that we don’t know how big the sun is. Also, per Dan, we are not even sure what the top of the sun looks like!)

2. Observe the world during the partial eclipse without looking at the sun itself: “Before totality watch carefully as the world darkens, notice the change in quality of the light, which becomes much sharper and appears more golden as the Sun disappears. Note the crescent shapes in shadows on the ground (which are caused by pinhole projections of the crescent Sun). Listen carefully to the sounds of nature; birds really do think it’s time to roost.”

3. View the partial eclipse with safety lenses on…but…. Okay this is a complicated one but it sounds really cool. “Just before totality: watch the sky darken in the southwest as the moon’s shadow races towards you.” What Dan is saying here takes some coordination. He’s saying to enjoy the partial eclipse with your eclipse glasses, but then, look away and take them off. Then watch the southwest sky.”

4. How to know when totality has begun. You can refer to the maps above and set timers on your phone or watches. But, per Dan, it’s pretty obvious. “If you’re not sure, keep looking with your eclipse glasses. When they are completely dark, it’s safe to remove them.” Interestingly, if you’ve removed your glasses to look at the shadows (as per tip #3), Dan adds that you probably don’t even need to put the glasses on again to confirm totality because “it gets so dark once the eclipse is total compared to even the faintest pinprick of Sun still showing. So, you should be able to tell.” Apparently, the difference between a partial and total eclipse is not the difference between “night and day” but between “day and twilight.”

5. What to do during totality. “During totality: take the glasses off as soon as the sun is fully gone. Take one photo of the sun and sky (it won’t be great but it’ll be your view) and one or two of the people around you. Then just look and listen.

   -Note the stars that appear as the Sun disappears.

   -Note the shape of the corona.

   -Pay attention to the weather too. All sorts of interesting things happen when you remove the sun from a 100-mile-wide chunk of atmosphere.

   -If you have binoculars, it’s safe (and worthwhile) to use those during totality too.

   -But mainly just notice the weirdness, the amazing sight of the Sun’s million degree atmosphere.”

Are you excited yet?! (In addition to being a wonderful scientist, Dan is also a great science communicator.)

6. What to do when totality is ending. “And at the end, same thing; as soon as you see a tiny pinprick of sunlight just look away [or set your timer, so you are warned]. If you’re using binoculars, maybe stop a few seconds before the end just for extra safety. After totality, look northeast to see the moon’s shadow racing away from you across the sky.”

7. Pray for good weather. Just kidding. But it’s always a gamble. Researchers like Dan—for whom the eclipse is an important opportunity to conduct science about the sun’s corona—chose their locations based on historical weather data. “We’re going to Texas, and the weather forecast is killing me. Could be fine, could be a disaster, but there’s no way to know right now, it’s just too far away. Every time I prepare for an eclipse I remember how stressful it is and how much I hate them — then as soon as I see the corona, I’m back in love.”

An historic eclipse.

How did Dan become a solar physicist who studies the corona? He met eclipse scientist Dr. Jay Pasachoff at Williams College (where Dan and I met and became good friends). As of now, Pasachoff has a unique distinction; he is tied for first among those who have seen the most total eclipses in human history. As it happens, Pasachoff’s career coincided with the dawn of affordable commercial aviation—meaning that scientists could fly anywhere in the world to see an eclipse. When Pasachoff passed away in 2022, he had seen 36 total eclipses. As a nice tribute in yesterday’s New York Times said, he inspired and mentored a generation of scientists, including Dan (who was quoted).

I met Jay a few times. The last time was memorable—and I have his family’s permission to share this. One day, I saw the name “Pasachoff, Jay” on the patient list in my ER here in Boston. I wondered if it was the Jay Pasachoff. I was not involved in his care, but I made a B line over to see him. It was indeed Jay and I make the connection. (It's always a thrill to meet people who have made special contributions to the world. I've treated famous orchestral conductors, Nobel Laureates, and, as it happens, the person who has viewed the most eclipses of any person in human history.) We briefly spoke about eclipses (and about our admiration for Dan) and that was about all. As an ER doc, when I get a chance to speak with a patient about something they care about (other than medicine), they really light up. Jay certainly did. I’d never seen one, I told him. He told me I just had to.

Weather permitting, I’ll see my first one next week—as will many of you. Keep in mind that the next one in the US will not be until 2033, and that only in a small part of Alaska. The next total eclipse that will occur in the continental US is not until 2044.

And the next one to hit Massachusetts? May, 1, 2079. It will be a month after my 100th birthday. I plan to attend.

Dr. Pasachoff (left) with some past and current students (2003). Dan is 4th from the left, looking destined to be solar physicist.

Images of the sun’s corona, made by Dan and his collaborators.

Dan and me, two months before Covid-19 hit, at which time I became interested in a different “corona.”

Questions? Comments? Experiences? Chime in!