Category Archives: eclipse

Total Solar Eclipse of September 10, 1923

A hundred years ago this month, the cover of the September 1923 issue of Science and Invention was celebrating the total solar eclipse that was to take place on September 10, 1923.

In the U.S., the path of totality covered only a tiny sliver of southern California, including the city of San Diego, as well as Santa Catalina and the Channel Islands. The best view, however, was in Mexico, since the path extended from Baja California to Yucatan. The Mexican National Government, as well as the governments of San Luis Potosi and Mexico City were heavily involved. The National Observatory and the Mexican National Railway were also assisting in preparations, and astronomers from around the world were preparing to descend upon the country.

Of course, we have two eclipses coming up in short order. The warm-up act will be the annular eclipse of Saturday, October 14, which will extend from Oregon to Texas, then into Mexico and Central and South America. It will also be visible as a partial eclipse in most of North and South America. Since the moon is currently too far from the earth for a total eclipse, the sun will appear to be a “ring of fire” along the path. While this phenomenon is certainly interesting, it’s not really spectacular.

The spectacular event is coming up on Monday, April 8, 2024, when a total eclipse will be visible along a line from Mazatlan, Mexico, and then in the United States and Canada, along a path from Texas through Maine. While the annular eclipse isn’t worth a special trip for most people, the total eclipse certainly is, just as it was a hundred years ago.

For the annular eclipse, and for all but a few minutes of the total eclipse, you will need eye protection to view the partially eclipsed sun. Our sister site, MyEclipseGlasses.com, has approved eclipse glasses available for only $3.99, with free shipping anywhere in the world. Just like eclipse glasses in 2017 (and just like toilet paper in 2020), they’ll be in short supply, so the time to order is now.

One Year Until the Eclipse!

Quick Links:

Hotel Rooms
Eclipse Glasses

One year from today, there will be another total eclipse in North America! As we did in 2017, we will provide full coverage of the April 8, 2024, total solar eclipse.

You might have remembered news stories about two big shortages in 2017: Hotel rooms and eclipse glasses.

Hotel Rooms

Many of the stories about hotels were exaggerated, with reports of alleged “gouging.” While a few run-down motels advertised astronomical prices, the reality was not quite that dramatic. In general, you were able to get a hotel room at the normal price, but if you didn’t make your reservations at least a few months in advance, most rooms were unavailable. We booked our room in Hastings, Nebraska, about 11 months in advance. So if you are planning to travel to the path of totality, whether it’s in Mexico, the United States, or Canada, it behooves you to make your plans now.

We haven’t made our final plans, but the official OneTubeRadio.com eclipse headquarters for the 2024 eclipse will probably be in Dallas.

For the 2017 eclipse, hotel rooms and other accommodations started becoming scarce a few months prior to the eclipse. A few rooms remained available up until two weeks prior to the eclipse.

In general, most hotels allow you to make reservations one year in advance, so if you want, you can make your reservations now.

Eclipse Glasses

The other item that will be in short supply will be eclipse glasses. You have plenty of time to order them online, so that you can safely view the eclipse. If 2017 (and other eclipses) is a guide, these will become totally unavailable in the weeks before the eclipse. People will be paying grossly inflated prices, and there will be rumors of counterfeit glasses. This time, we decided to get in on the fun, and we will be selling eclipse glasses. We have started a website, MyEclipseGlasses.com, where you can order safe American-made eclipse glasses at a reasonable price. Our glasses are made in the USA by American Paper Optics. Their website contains an excellent resource explaining eclipses, and includes a one-hour on-demand video presentation.

Schools and the Eclipse

If you have kids who will be in school, plan on taking them out of school that day. Unfortunately, the 2017 eclipse showed that some American schools had an irrational fear of the eclipse and actively prevented children from witnessing it. If you believe that your child’s school is more enlightened, then on the first day of the 2023-24 school year, or maybe now, you should have your children ask the science teacher if the school is planning a field trip to see it. If the teacher balks, then your children should let him or her know that they will be absent the day of the eclipse. At the very least, you should ask whether your children’s school has purchased eclipse glasses for the event. If they buy in bulk before the eclipse, they can be had for pennies. But if they fail to plan and wait until the last minute, they will be unavailable, or selling for outrageous prices.

A field trip to see the eclipse is an entirely reasonable request for most schools. For example, students in Chicago could be placed on a school bus and taken to see the eclipse only a couple of hours’ drive away in Indiana. The expense will be less than other field trips taken to amusement parks, movies, etc. This is true for schools in many cities. They have the opportunity to let the kids witness an amazing scientific event, but only if they do some basic planning.

But I predict that this won’t happen, since most schools won’t think of the possibility until after it’s too late to make the necessary plans, or they’ll have the same irrational fears that showed up in 2017. It’s the duty of the students to pester the administration so that the necessary plans are made sufficiently in advance. And as I explained in 2017, if the school fails to act, then it’s reasonable for children to skip school on April 8, 2024.

October 14, 2023 Annular Eclipse

Path of October 14, 2023 Annular Eclipse.

There is another eclipse, an annular eclipse, on October 14, 2023. That event, while interesting, is nowhere near as breathtaking as a total eclipse. So if you happen to be close, you should take in the 2023 event. But the 2024 total eclipse is in an entirely different league.

The 2024 total eclipse will be visible in parts of Texas, Oklahoma, Arkansas, Missouri, Illinois, Indiana, Ohio, a tiny slpeck of Michigan, Pennsylvania, New York, Vermont, New Hampshire, and Maine. The path of totality also passes through Mexico and Canada. Major cities in the path of totality include Dallas, Little Rock, Indianapolis, Buffalo, Cleveland, and Montreal.

Please don’t be confused when you hear about “percentages” of eclipse. Some people are lulled into believing that since they will experience a “90% eclipse” at their home, or even a “99% eclipse,” that there is no need to travel. This is a big mistake. Even with a 99% eclipse, the experience is completely different from a total eclipse. Unless you are paying attention, you might not even notice the 99% eclipse. But you’ll definitely notice the total eclipse just a few miles away, since it will become noticeably dark outside.

Partial Solar Eclipse of 25 October 2022

NSF image.

On 25 October 2022, there will be a partial solar eclipse over most of Europe, northern Africa, the Middle East, and western Asia. While not nearly as spectacular as a total solar eclipse, if you are in the area where the eclipse will be visible, it is certainly worth observing.

National Archives image.

Since the sun is never completely obscured, it is dangerous to look directly at the sun. However, you can view it indirectly by projecting it, as shown in this picture. You can use a pair of binoculars or telescope to do this. You do not look through the binoculars or telescope. Instead, you point the binoculars at the sun, and point the other end at the ground or other flat surface. You will then see a projected image.

While this picture shows a relatively expensive telescope, this is not necessary. A good image can be projected with even a pair of toy binoculars. See the NASA website for more ideas on viewing the eclipse. You can also view our page from the 2017 U.S. eclipse.

The eclipse will be visible first over Greenland at 08:58 UTC, and will end over India at 13:02 UTC. The peak eclipse will be visible over Siberia at 11:00 UTC. To find the exact times for your location, use this interactive map.

Those with an interest in radio will want to experience how the partial eclipse affects radio propagation. During the 2017 eclipse, I found that there was a very noticeable effect on propagation on 40 meters. Those with just a mediumwave or longwave receiver will probably discover that stations normally heard only at night can be picked up during the day, due to the eclipse.

Solar eclipses and lunar eclipses come in pairs, about two weeks apart. The corresponding lunar eclipse will be visible in North America on November 7-8.

Popular Science: 1872-2022

1972MayPS

This month marks the 150th anniversary of Popular Science, or at least the predecessor of what we know as that magazine. The original magazine, whose first issue was published in May 1872, was a scholarly journal of about a hundred pages, with about ten articles, and just a few illustrations. The rights to the name were acquired in 1915, and the October 1915 issue resembles the modern incarnation of the magazine.

The first issue contained articles on topics such as the study of sociology, an essay on science and immortality by Rev. T.W. Fowle, the source of labor, Quetelet on the science of man, and disinfection and disinfectants. One of the few illustration is this sketch of the sun’s corona, illustrating an article about the solar eclipse of December 12, 1871.

In April 2021, the paper edition of the magazine ended, and it exists now only in digital format. All issues from 1872 through the early 2000’s are available at Google Books for free reading.

The image shown above is the cover from May 1972, celebrating the 100th anniversary. The magazine used the occasion to publish a review of its first hundred years, and used copies are available at the followng links. As with many used books, prices can vary wildly, so be sure to compare prices at all of these links:

Current subscriptions to the digital magazine are available at the following link:

Some links on this site are affiliate links, meaning that this site earns a small commission if you make a purchase after clicking the link.

Eclipse of April 8, 2024

2024 Eclipse Path. NOAA image.

As we did in 2017, OneTubeRadio.com will provide full coverage of the April 8, 2024, total solar eclipse, which will take place two years from today.

For the 2017 eclipse, hotel rooms and other accommodations started becoming scarce a few months prior to the eclipse. A few rooms remained available up until two weeks prior to the eclipse.

In general, most hotels allow you to make reservations one year in advance. Therefore, if you plan to see the eclipse in an area experiencing totality, which we strongly recommend, then you should plan on booking a hotel room on April 8, 2023. For the 2017 eclipse, we booked a fully refundable hotel room, so there was no risk if we changed our plans. In 2024, we’ll probably view the eclipse in Texas, although our plans are not settled. For the 2019 annular eclipse, we had contingency plans that included both a hotel and campground in Canada, and a campground in the U.S. Since the border was still closed, we cancelled the Canadian reservations, since we made sure to get fully refundable ones.

Speaking of annular eclipses, there is one of those on October 14, 2023. That event, while interesting, is nowhere near as breathtaking as a total eclipse. So if you happen to be close, you should take in the 2023 event. But the 2024 total eclipse is in an entirely different league.

The 2024 total eclipse will be visible in parts of Texas, Oklahoma, Arkansas, Missouri, Illinois, Indiana, Ohio, a tiny piece of Michigan, Pennsylvania, New York, Vermont, New Hampshire, and Maine. The path of totality also passes through Mexico and Canada. Major cities in the path of totality include Dallas, Little Rock, Indianapolis, Buffalo, Cleveland, and Montreal.

Also, in late 2023 or early 2024, you should order your eclipse glasses.

If you have kids who will be in school, plan on taking them out of school that day. Unfortunately, the 2017 eclipse showed that American schools had an irrational fear of the eclipse and actively prevented children from witnessing it. If you believe that your child’s school is more enlightened, then on the first day of the 2023-24 school year, you should have your children ask the science teacher if the school is planning a field trip to see it. If the teacher balks, then your children should let him or her know that they will be absent the day of the eclipse.

This is an entirely reasonable request for most schools. For example, students in Chicago could be placed on a school bus and taken to see the eclipse only a couple of hours’ drive away in Indiana. The expense will be less than other field trips taken to amusement parks, movies, etc. This is true for schools in many cities. They have the opportunity to let the kids witness an amazing scientific event, but only if they do some basic planning.

Eclipse Report: June 10, 2021

Wikimedia Commons photo by Anthony Quintano from Mount Laurel, United States – Statue of Liberty Annular Solar Eclipse, CC BY 2.0.

As we previously reported, we travelled to near Grand Marais, Minnesota, on the North Shore of Lake Superior, to view the annular eclipse of June 10, 2021. You win some, and you lose some, and we lost this one, as the event was completely clouded out.

Local sunrise was at 5:05 AM, and we should have seen a view similar to the one above (but probably without the Statue of Liberty). Unfortunately, we awoke at about 3:00 to the sound of rain, and the weather within a hundred miles driving distance reported cloudy.

We set out in hopes of finding a hole in the clouds, but with no luck.

The photo above was taken by New Jersey photographer Anthony Quintano, whom we thank for releasing this image on a Creative Commons license. Prints are available at his website.

Annular Eclipse, June 10, 2021

Eclipse of May 31, 2003, Bavaria. Wikimedia Commons image by Sch, licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license.

On Thursday, June 10, 2021, much of North America will experience a sunrise similar to the one shown above. As we previously reported, on that day, there will be an annular eclipse of the sun. Normally, this isn’t a really big deal, since enough of the sun remains visible so that it doesn’t get noticeably dark outside. But this one is an exception, since it takes place at sunrise. Depending on your location, as the sun rises Thursday morning, the sun will be either a crescent or a ring.

The map below (courtesy of Michael Zeiler, GreatAmericanEclipse.com) shows approximately what the sun will look like at sunrise. In some cities, such as Minneapolis and Chicago, there will be a noticeable chunk missing from the sun as it rises that morning. Other cities, such as New York, Philadelphia, Washington, and Toronto, will have only a tiny crescent sun come over the horizon.

This map shows simulated views of the partial eclipse at sunrise. To get this view, you’ll need approved solar viewers. In general, you will get the most dramatic views of the rising eclipse along the middle curve of the three curves in this map.

As the sun is rising, it’s as safe to view as any other sunrise. But as it goes above the horizon, if you want to keep watching, you’ll need eclipse glasses or an indirect viewing method. If you still have glasses from the 2017 eclipse, you’re all set. You can also use indirect methods, as we discussed in 2017.

My original plan was to view the eclipse near Longlac, Ontario at Macleod Provincial Park. Unfortunately, the border remains closed, and it looks likely that the park will remain closed to camping due to COVID. Therefore, the official OneTubeRadio.com eclipse headquarters will be located at Cascade River State Park, near Lutsen, Minnesota. While there probably won’t be a good view of the sunrise from the campground, we will use the day before the eclipse to scout out a spot along the shore of Lake Superior to view the sunrise. That campground is fully booked, but the last I checked, there were a handful of sites available at Judge C.R. Magney State Park and Gooseberry Falls State Park. There are also some hotel rooms available in the area.

Similarly, if you’re in Chicago or Detroit, it’s worth the drive to Sault Ste. Marie to view the crescent sunrise. And if you live in New York, Philadelphia, Toronto, or Washington, all you need to do is set the alarm clock early, and find a good place to watch the spectacular sunrise.

Science Fair Ideas: Measuring the Moon’s Diameter

If Junior is looking for a science project that can be completed in one evening, the teacher will be suitably impressed when Junior announces that he will measure the diameter of the Moon. All that’s required is a window through which the moon is visible and a couple of pieces of tape. Masking tape would probably work the best, but you could also use a couple of Post-It notes. You’ll also need a card through which you cut a hole.

Place the strips of tape on the window 1-1/4 inches apart. Then, you move the card away from the window, and keep looking through it until the moon appears to fill the space between the two pieces of tape. Measure the distance between the card and the window. At this point, the proportion of the two distances is the same as the proportion between the moon’s diameter and the distance between the moon and the earth.

Let’s say, for example, that Junior measures the distance between the card and the window as 137-1/2 inches. (Ahem, and if he does the experiment correctly, that’s the number he should get, assuming that the moon hasn’t changed size.)

According to NASA, who has been there, the moon is 238,855 miles from the earth. So we have a ratio:

1.25 / 137.5 = X / 238,855

If Junior’s algebra is a little bit rusty, he can use this online calculator to get the answer of 2171.4 miles. According to space.com, the actual diameter is 2159.2 miles, so we would say that Junior’s method is pretty close.

The experiment appeared 80 years ago this month in the February 1941 issue of Popular Science, which also carried some other astronomy experiments and demonstrations. For example, shown here is a demonstration of a solar eclipse, using a lamp for the sun and a tennis ball for the moon. One of these would be an excellent project in preparation for the June 10, 2021 annular eclipse or the April 8, 2024, total solar eclipse, both of which will be visible in North America. The magazine even shows how to demonstrate the orbit of a comet using an electromagnet to simulate the sun’s gravitational pull on a steel ball simulating the comet.

Eclipse of June 10, 2021

Wikimedia Commons image by Sch, licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license.

The photo above was taken in Bavaria at sunrise during the eclipse of May 31, 2003. That was an annular eclipse, meaning that the sun is never entirely obscured by the sun. Because the moon is slightly too far away, there remains a ring of sunlight. It’s essentially the same as a partial eclipse, in that the world does not get appreciably darker. It’s an interesting phenomenon, but not particularly amazing. In most places, if nobody told you it was in progress, you might not even notice. For example, I drove to Springfield, IL, to see the annular eclipse of May 10, 1994. It was somewhat interesting, but there really wasn’t much to see.

There are two exceptions however, one of which is shown in the photo. At sunrise and sunset, the disc of the sun is visible. So if the annular eclipse (or a partial eclipse) is happening at sunrise or sunset, it will be quite apparent.

Path of June 10, 2021, eclipse. NASA image.

There will be an annular eclipse in North America on June 10, 2021. It’s drawn little attention, since most of the path of annularity will be over unpopulated areas in Northern Canada, Greenland, and Siberia. Much of the Canadian path is over Hudson Bay and James Bay. So unless you’re one of the few thousand Canadians living in the path, the event will be of little interest.

However, the one exception where the eclipse is visible over inhabited areas is also the one place where the phenomenon will be most interesting: The partial or annular eclipse will be visible at sunrise in Northwestern Ontario, near the city of Thunder Bay. In Thunder Bay, the sun will be about 70% covered by the moon at sunrise, and the sunrise should clearly show the partially eclipsed sun. Just a few miles northeast of Thunder Bay, there will be an annular eclipse at or near sunrise, which should result in a view similar to the one shown above.

I have two viewing locations in mind. I’ve already made a hotel reservation in Longlac, Greenstone, Ontario, which is 305 km from Thunder Bay along the Trans-Canada highway. The lawn in front of the hotel seems to have a good view of the sunrise. From my home in Minnesota, it’s about a 9 hour drive. That’s actually my backup plan, since I was already able to make a refundable hotel reservation. My primary viewing location is Macleod Provincial Park, where the campground is next to a lake, which seems to have a good view of the sunrise. Camping reservations, however, are only available five months in advance. So in January, I plan to make reservations, and after they are secured, I’ll cancel the hotel in Longlac (and I’m sure it will get snatched up quickly, since it’s one of the few hotels in the path of annulaity.)

It should be a spectacular view, but there are two possible problems. The first is the possibility of cloud cover, since there appears to be cloud cover about 60% of the time in this part of Ontario. As we did in 2017, we’ll just have to hope for the best, and perhaps plan to drive a few miles to a break in the clouds.

The other potential problem, of course, is COVID-19. Since March, the U.S.-Canadian border has been closed to non-essential travel, and this trip is clearly non-essential. Again, I’ll have to hope for the best. If the border remains closed, there will be about 16% coverage of the sun at sunrise at home in the Twin Cities. So it won’t be particularly spectacular, but it will be worth getting up to view.

But as one heads northeast, the coverage gets greater. For example, in Duluth, MN, there will be about 40% coverage of the sun as the sun rises over Lake Superior. Just south of the border at Grand Portage, the coverage will be about 70%. Anywhere along the North Shore of Lake Superior between these two points, the view should be spectacular as the sun rises over the lake. So if the border is still closed, that’s probably where I will be.

Other cities in North America will experience a spectacular sunrise that morning. In Toronto, for example, the coverage will be about 72%. Philadelphia, New York, and Boston will all have coverage of more than 70%. Winnipeg will have about 40% coverage at sunrise, and much of Saskatchewan will have at least some coverage at sunrise. Further west, Fairbanks, Alaska, is the only other North American city with anything to see, with about 24% coverage at sunrise.

October 1, 1940 Eclipse

Today marks the 80th anniversary of the total solar eclipse of October 1, 1940, which was visible in Colombia, Brazil, Venezuela, and South Africa.

One focus of research for this eclipse was its effect upon the ionosphere and radio propagation. As shown from the clipping above (Washington Evening Star, Oct. 1, 1940), scientific teams from the National Geographic Society and Brown University had travelled to Patos, Brazil, and had photographic equipment at the ready. Unfortunately, however, a thick layer of clouds prevented visual study. Other experiments, however, focused on radio propagation and were presumably unaffected by the clouds.

In preparation for the radio studies, the National Bureau of Standards had previously published data regarding normal ionospheric conditions on the date of the eclipse.