Thursday, 20 July 2017

Eclipse stuff galore!

The American eclipse this summer has produced one thing, more kitsch (stuff) than you can imagine. There is eclipse fever running in the market. So far I have come across Eclipse beverages (the best being Eclipse Moonshine), Eclipse foods, Eclipse shirts, Eclipse hats, Eclipse buttons, Eclipse tattoos, and virtually any marketing gimmick you can think of.

Cartoons - I have added over 200 cartoons to the eclipse nuts web page. Many are about the solar eclipse this summer. And I have been asked by several people if they could use the cartoons for t-shirts. As long as the application is not for commercial purposes, I am cool with that, just send me a picture of you wearing the cartoon shirt after the eclipse!

Art work - here is an example by Clare Casey of some very cool artwork associated with the eclipse. I am looking forward to seeing more examples after the eclipse as artists are inspired to try and capture the feeling of totality. A gallery of eclipse art can be viewed here.

Need new clothing? This year is proving to be a treasure trove of shirts and hats. All that is missing is eclipse pants, socks, shoes, shoe laces, and maybe even some underwear. In the picture below I am wearing a shirt and hat from GreatAmericanEclipse and I just recently got a newer shirt from them called "Occupy Totality".

Snail Mail Anyone? Even the post office is getting into the game with eclipse stamps that contain "magic" ink. When heated you can see the Moon! When cooled you can see the dark Moon eclipse. I bought mine in Florida. They were dark until I went out to my car. And they didn't turn dark again until I got them into the air conditioning. These stamps are unique, last forever, and very cool. Get them at the US Post Office while you can.

And there is more to come.... stay tuned for a later blog entry! If you know of anything cool related to the eclipse, please send pictures or a link or leave a comment below.

Monday, 17 July 2017

Eclipse 2017 - the big one!

I was talking with a reporter who asked how I felt about the "big eclipse" coming in August. I had to snicker. It isn't a big one. Let me explain.

Just how Big?

In terms of "big eclipses", the August eclipse isn't all that big. Eclipses are measured in time. The time that the Sun is completely blocked by the Moon is called totality and we measure the duration of totality.

From the perspective of duration the August 2017 will not be a particularly long eclipse. The maximum duration does not even crack three minutes. Eclipses can last up to seven minutes (for ground observers) so this one does not even make it to the middle of the scale. It is below average.

I suppose another way to measure eclipses is how many people may get a chance to see it. From that perspective, the August 2017 eclipse ranks up near the top. A lot of people could potentially see it, many with a relatively easy drive (under normal circumstances) to the central path.

In comparison, the eclipse of July 2009 was a really big one. Not only was that eclipse a long one in terms of duration (longest in the 21st century) it crossed heavily populated areas like Shanghai in China. The eclipse path started in India (also a highly populated place) before crossing the mountains into China and then out to the ocean.

An American Eclipse

This eclipse is unique in one big aspect. It crosses the lower continental USA and no other countries. That is a lot of land mass (an entire continental width) to cover and still only be one country. Of course, that is partly because the USA is a big country.

The USA has 50 states,  two of which are not directly connected (Alaska and Hawaii). The other 48 states are sometimes called the lower 48. They make up the familiar shape of the USA. This eclipse crosses the lower 48.

There has not been an eclipse path in the lower 48 since 1979. That makes it a big thing, especially if you are American. Hawaii did get to see a total, a rather long one at that, in 1991. By comparison that is a small population and land fall amount compared to the August 2017 eclipse. Still, that has been a long wait for many.

For people who reside outside the USA, this eclipse is a bit of a hassle. Especially if you come from countries under travel restriction or quotas. The USA is not always an easy place to visit for some. Visa application fees expensive (about $160 each time you apply) and he process can be difficult. An embassy visit might be required and so forth. Thus the "Big One" is not as attractive for some eclipse chasers that live outside the country.

Solar Minimum

The August 2017 eclipse is occurring at solar minimum. That means that the Sun has fewer sunspots than at Solar Maximum. Sunspots are storms or disturbances on the surface of the Sun. During a total solar eclipse they are seen along the edge in the form of prominences. Plus they can cause interesting shapes and twists in the solar corona.
1983 Corona shape near sunspot minimum - Bill Kramer
1991 Corona shape near sunspot maximum - Bill Kramer

Is solar minimum a bad thing for solar eclipses? No, it just means that the corona might not be as bright and rounded. In fact, the shape of the corona will most likely be quite interesting with short polar brushes and coronal wings extended out along the equatorial directions. The eclipse in 1983 (see image above) was nearer to minimum and it appeared as a butterfly in the sky. For comparison a very active corona can be seen in the 1991 eclipse. Eclipses at solar minimum often exhibit very complex coronas so it will be interesting to see what we get.

For a preview of the coronal shape, see the SOHO web site.

So it will NOT be big and great?

It is going to be great, don't get me wrong. All eclipses are great. It just won't be a particularly long eclipse. And there will be a big audience to see it. It is summer time and the chances of good weather along the path are quite high.

Trust me, it will be Great! It will be Big! You are gonna love it!

However I tend to think of this eclipse as the "Easy One". Since I am America I have no travel issues other than getting to the central path and finding a hotel. We booked a hotel quite a while ago that would be easy to reach for us and family and friends. That was easy. There were a lot of choices. By getting a hotel in advance we avoided the increased costs others are finding as they look now, nearer to the big event. So not only was it easy, we got a good discount by booking a block of rooms for our friends and family. This one was relatively cheap.

It was not like trying to find a hotel or lodge in the middle of some jungle or out in the ocean. No exotic transportation is needed, we can drive a car. This one is EASY! That makes it a Great American Eclipse indeed!

Now then, as to the name "The Big Eclipse" - it is a book for kids. A well done book at that! Check it out at

Saturday, 15 July 2017

The Eclipse Chaser Community

The eclipse this year has been interesting as numerous reporters are keen to get a scoop or some sort of unique angle on the story.

One question I am asked repeatably regards the "eclipse chaser community". It is because of the web site - - that I started back in 1999. My original intent was to simply put my own eclipse chasing experiences up on the web. The community aspect was never part of the plan, it was intended to be a tool to keep track of past eclipses and share ideas for future ones.

I had never thought about the community concept before the questions began to appear. Yes, we do have conferences and meetings, but a community?

Group photo at an eclipse conference

Do we have a community?

One could argue that the various astronomical societies serve as a type of community. The American Astronomical Society, the International Astronomical Union, and Astronomers without Borders are just a couple examples. These types of communities focus on astronomical things like research, education, and public outreach. These are not really communities as much as organizations. There are officers, there are rules, in some cases there are even dues to join. Within these organizations one finds communities of common interests, yet none really cover eclipse chasers.

Eclipse chasers are an amorphous collection of communities at best. I must qualify that statement as being from my perspective. As viewed by an outsider, a reporter for a newspaper looking for a story, we are all one big community.

So here is how I break it down for the reporters that have asked.

Shared Interest Groups

On Facebook and Yahoo you can find some eclipse chaser groups. They range in size from a couple of people on up to several hundred. Many overlap in that they are the same members in the multiple groups. On the mailing list oriented group discussion ranges from the absurd to the technical about eclipses. In general the conversation is very well controlled thanks to it being moderated by a true diplomat amongst people (thank you Mr Gill). The Facebook groups tend to get infiltrated by various lurkers and vendors making them less popular with the more technical crowd. They are fun in that some of the topics tend to be more about silly and absurd aspects of eclipses and travel.

The log at the web site includes over a hundred members and they represent a sizable fraction of the eclipse chasers out there. The list is by no means complete. There are some who refuse to be put on it for what ever reasons. As the programmer of the log, I just hope it is not because it didn't work for them and they got frustrated.


All eclipse chasers must travel. If you just wait for an eclipse to happen in your neighborhood, you might find yourself very limited. Even the luckiest neighborhood may see only one or two eclipses in a life time. Eclipses cross a place at an average rate of once every 350 years or more. Yes, there are lucky places. Like Carbondale Illinois where one can see an eclipse in August and again in April 2024.

Thus eclipse chasers have to travel to see multiple total eclipses. When traveling around the world to these events you do get to meet the same people over and over again. Of course, group rates can help at times too. If you have a band of eclipse chasing friends it is possible to secure excellent places to stay and methods of transport to get there. This can be very important when considering costs. Unlike the popular myth that all eclipse chasers are wealthy there are some who do have to struggle financially to get to the various eclipse locations. Obtaining a group rate saves a bit here and there, may even result in a few free rooms, and that helps everyone out.

In addition to the band of friends you can also find travel companies. They use the group rates and then package the entire thing into a product one can join. Loyalty to travel companies is common as they often bring astronomical expert/celebrities along and market to past customers aggressively. You don't save much money traveling with tour companies but you do develop good friends and find others who share your passion for eclipses. Most of the travel/tour companies do an excellent job at providing the type of experience one would want when going to different parts of the world chasing eclipses.

In my opinion there are traveler communities inside the eclipse community. Most are quite diverse in their make up. They may have serious astronomers, amateurs, families, retirees, friends, and who knows what else in their ranks. I have met a variety of people ranging from what some would call the super-rich to recent (unemployed) graduates spending their gift money. Many of us save up just for eclipse travel and don't bother with the more traditional types of vacations. (In my situation we did a lot of camping vacations to save from one year to the next before splurging on something special - a solar eclipse.)

The key to eclipse chasing travel is that it is travel with a purpose. Everyone shares the same goal, to see the eclipse. The other stuff is a bonus extra. Others might say something about always wanting to visit where ever as well as see the eclipse. Thing is, it all comes down to the common goal of seeing the eclipse. And that makes us a community. We travel with a purpose.

Calculators, Computers and Map makers

The other sub-community within the global eclipse chasers group are those of us that enjoy the challenge of calculating eclipse paths, making maps for others, and computing various details related to the eclipses. There is no real formal community here, just a bunch of people who share that interest.

There are quasi-professional groups such as the IAU WGSE (International Astronomical Union Working Group on Solar Eclipses). The IAU WGSE presents papers and has a goal of promoting eclipse knowledge. We don't have meetings. We mostly just use email to share information, even then not very often, and it is mostly consists of requests to check each others works.

This is a very small community at best. Some skills are required and then one must want to share with others.

Yes, we are a community

So in thinking deeper about the question, yes there is a community of friends, associates, businesses, professionals, and others who share a passion about solar eclipses. It really is something you need to see to understand how this can happen. A diverse group of people, some highly educated and others who never finished school are all attracted to one of nature's most amazing shows. It just goes to show how powerful the total solar eclipse experience can be for people.

A Follow Up

A question that was asked after this entry was published related to the number of eclipse chasers out there and if they are all Americans. Getting a count on eclipse chasers is difficult as it is not something everyone will admit to being. There are over 300 chasers listed in the log. Yet the Solar Eclipse Mailing List has over 500 members. So if we double that number we get about 1000 serious eclipse chasers.

Now what about the not-so-serious eclipse chasers but people who do go to solar eclipses. These would be people who have seen more than one eclipse. I'd estimate there are several thousand people in this category. During the eclipse of 1998 almost a dozen cruise ships carried over a thousand people each into the path of totality. The eclipse of 1999 had several cruise ships in the Black Sea along with eclipse chasers from England all the way to Iran.

And eclipse chasers are international. It is the nature of the game. Not only do Americans enjoy it, so do other nationalities. I host an English language eclipse chaser web site yet I get visitors from all over the world every day. There are eclipse web sites in other languages too. Solar eclipses are something every living human being can enjoy.

So how many eclipse chasers in this community? I don't know, quite a few is my guess.

Monday, 10 July 2017

Eclipses on other planets?

Is the Earth the ONLY planet to enjoy a solar eclipse?

Virtually any astronomer can assure you that eclipses are not an uncommon thing. An eclipse occurs when one object casts a shadow on another such as when the Moon's shadow hits the Earth. That is when a solar eclipse takes place. When the Earth's shadow hits the Moon, a lunar eclipse takes place. Using a modest backyard telescope one can see the shadow of the Jovian moons hitting the upper cloud decks of Jupiter causing a solar eclipse there. And if the angle is right one can also see the moons of Jupiter emerge or get engulfed by the shadow of the giant planet.

Thus the simple answer is that Earth is not the only planet to enjoy eclipses.

But do they see really good eclipses on other planets? A good eclipse is where the apparent size of the eclipsing moon is the same as the size of the Sun in the sky. Here on Earth the Sun and Moon appear to be about the same size in the sky. The reason is one of perspective. The Sun is massive. 400 times bigger than the Moon. Yet it is 400 times farther away making it look the same size.

You can see this effect by using two coins, a big one and a small one. Put the larger coin on your desk and hold on to the smaller one. Now block the view of the big coin with the small one by holding the smaller one closer. (It helps to close one eye.) Move the smaller coin back and forth until it matches the size of the larger, more distant coin. Now measure the distance to the larger and smaller coins. Also measure the size of the two coins. If you compare the ratio of the larger value over the smaller value you will find they match up. (Example, two coins, one is three times larger will match in size if the larger coin is three times further away. Try it!)

Now back to the question about the other planets. Do any of them have a moon that appears to be the same size as the Sun? There are over 180 known moons in the solar system and they vary in size greatly. There are moons that are very big and there are moons that are very small (kilometer or so).

To figure this out the first step is to determine how big the Sun appears from the other planets with moons. All of these planets are further away meaning that the Sun will look smaller to someone observing from that location.

The next step is to find out about the various moons of the planets and determine how big they appear in the sky.

Now we can compare the sizes to see if any match up or come close. Given the diversity of the solar system moons there will be some that appear to be many times the size of the apparent Sun as well as some that will be mere dots in the sky. And as we reach farther and farther away, the Sun itself starts to appear as a dot. This means we would need a powerful telescope to see the eclipse.

The results of one such analysis I did can be viewed at:

I created a table of just over 100 various moons with various sizes and found, as expected, that an exact matching ratio is rare. Just not as rare as I anticipated.

It was expected to find that only the Earth and Moon had such an arrangement of matching angular sizes. But what I found were two other moons, Pandora and Epimetheus both in orbit about Saturn, also has a near perfect fit just like the Earth and Moon! Check out the study to see which moon was actually the best.

The study revealed at least three more moons that create total eclipses where one could see the corona all the way around the eclipsing moon. I say at least because that is a subject open to debate. I set the test up to look for any circumstance where the moon was two times the size of the Sun or less. That means the corona must be visible out two solar radii, not an uncommon situation (the corona can be seen out to six solar radii with dark adapted eyes from inside the Earth's atmosphere, so one could increase this cut off level and see even more matching situations).

It turns out that such coincidences are not as rare as I had believed!

There is quite a range in sizes. The moon Triton  appears 26 times larger than the Sun from Neptune! Now this does not mean it fills the sky. Neptune is pretty far away from the Sun. Without a telescope, the Sun would appear as a bright dot in the sky. Triton appears to be about half a degree, the same as our Moon appears to us over Earth. On the other end of the scale some moons appear to be a dot against the solar disk. The worst case was the Sun appearing over 16,000 times larger than the eclipsing moon!

BUT - this is important!

The eclipses of the Sun as seen from the Earth are the best. Why? Earth is the closest planet to the Sun with a natural moon in orbit. And thus it has the closest view. From Saturn, we would need a 10x telescope to see the same thing we see with the naked eye from the comfort of Earth.

cartoon by Bill Kramer

Wednesday, 5 July 2017

Eclipse Book Review - American Eclipse

There are a lot of eclipse books suddenly available. Most contain maps and details about the eclipse this summer and I do have some recommendations on that subject. Fred Espenak's books are the best overall. You may have seen his web sites about eclipses, and are the most popular. Go to Eclipse Wise Publications page to see his books about the eclipse - great information and great maps!

And there are some fun books for nerds.

One I just finished reading is titled American Eclipse by David Baron. I was impressed with the amount of research that went into this book about the eclipse of 1878. Having little to no knowledge of the eclipse other than some referenced in books from that era it was fascinating to follow along as David tells the stories of several eclipse expeditions into the American frontier. The expeditions included some famous names of the day such as Edison who was testing a device to measure heat from stars and the solar corona. A charged political atmosphere of the time is highlighted putting the entire story into a neat perspective that left me feeling like I had experienced the journey myself. I cannot say enough good stuff about the writing style. It was fun. The descriptions of the eclipse were by someone who has been there. I liked the descriptive text and may end up borrowing some of the phrases in future eclipse writings and talks. If anything to add some variety to the descriptions I often use to convey the eclipse experience.

I picked up the book while in a Barnes and Noble book store. The number of astronomy and science books are few and rarely seem to change. I always check to see if anything new showed up any time I am in the store. This book was just published, obviously in time to market for the eclipse this summer. Anyone who likes history is encouraged to take a look at it. It is extremely well researched and written. Plus I found at the end a nice dedication to fellow eclipse chaser Jay Pasachoff who the author claims inspired him to do the project and see more eclipses. Good job Jay!

When I described some of the hardships the chasers in the book encountered to Denise she remarked that I should write up about our adventures in 2002. While we were not cold like some of the campers in Wyoming and Colorado in 1878, we did experience some "discomforts". But that's another story....

Friday, 30 June 2017

Just how fast do you need to go?

This question has come up more than once recently. And from some pretty strange sources. If someone wanted to view the eclipse from the west coast to the east coast, how fast do you need to go? There are those that have access to aircraft and wondered if it was possible to keep up with the shadow of the Moon as it raced across the continent from Oregon to South Carolina.

As a quick answer, you need to go pretty fast. Like in the range of 1400 to 2400 MPH. That is pretty fast. Supersonic!

The average overall speed would be just over 1600 MHP based on a distance of around 2500 miles in about an hour and a half. At first the speed would be higher, in the 2400 MPH range. That is because the shadow is hitting at an angle. It is more oblong in shape (like a football) but that doesn't matter much because we need to keep up with it. The shadow speed slows as the eclipse reaches the part of the globe that sticks out the most, near Illinois/Kentucky/Tennessee. At that point it is "only" doing about 1400 MPH.

Is there an aircraft that can do it?

Turns out yes, there are several aircraft that might have a chance. The problem is how far can they run at that speed. Most might need to slow way down to fuel up the tanks and by then the shadow has out run them.

In 1973 a prototype of the SST Concorde raced the shadow of the Moon across Africa. It was able to keep up for an astounding 74 minutes before breaking off. The thing is, there are no windows looking up from the Concorde, just a small area for instruments to be placed. They could see out the window, not the eclipse, but the shadow sweeping over the land below.

What about those super spy planes, can't they go that fast? Again, they can but not for long. They go even faster otherwise they might burn up the fuel too quickly. So while they can run at the speed for a short while they would either have to slow down and fuel up or jump way ahead and make a loop about the shadow thus not staying under it the whole time.

14 or 12 states?

If one wanted to see the eclipse from every state that touches the umbra the problem is one of geometry. Up in the air you are outside of the shadow! It is hitting the Earth at a slight angle and is shifted to the South the higher up you go. For 2 of the 14 states the umbra makes a glancing blow at surface level - but not up where the jets fly! I suppose now we need to see what states to the south of the central path might need to be added to the list of states crossed at jet elevations....

Thursday, 29 June 2017

Planning your eclipse day

It seems every journalist in the USA is taking a stab at writing a piece about solar eclipses. This is great! Finally we get to tell the story. You see, a total solar eclipse is an experience.

  • For some it starts years before the actual event. They are considered the eclipse chasers
  • For some it is just like any other day. They are innocent by standers
  • For the rest it is another day on vacation with an eclipse chaser. They are groupies.

I am writing this blog entry is for the eclipse groupies.

This is kind of what it will be like to experience your first eclipse in the company of an eclipse chaser.

Morning, sunrise:

Eclipse chasers have been frantic about weather and other secret contingency planning. They probably did not sleep the night before. Chances are good that this will be the first time you are actually looking at the weather with any real concern. You are wondering whether or not it will cooperate during the solar eclipse. The sleep deprived chasers will be the first clue. If they are frantically loading up to move, you should join in and help - after you have some breakfast and coffee maybe.

But let us assume the location is deemed good and proper so there will be no moving to a new one in the early hours. Now you can sit back and watch the dance of the eclipse chasers.

If the eclipse is in the morning, before noon, then the eclipse chasers have been set up since sunrise (if not hours earlier). 

If the eclipse is in the afternoon, then the eclipse chasers have been set up since shortly after sunrise (if not hours earlier). 

Generally the eclipse chasers will stake out an area to view the eclipse, sometimes days in advance. The location may be marked with tape or a small sign. Most will wait until eclipse day with the most concerned members being up early and putting up tripods or other equipment to define a boundary.

They will choose a location based on many reasons. Some want the landscape view, others want an unobstructed view, some want specific silhouettes visible, while others choose a space way bigger than they need so they can select who sets up near them. Other considerations may be a desire to be near a scarce resource like electrical power or to best observe shadow bands. What ever the reason, most will follow where ever the more experienced eclipse chasers in the group locate so they can see what they are supposed to do. They also like to be near the expert so they can ask questions should something come up (at this time it is either equipment set up or camera related).

First Contact:

First contact has a big build up with little to actually see. The Moon is just starting to cover the Sun. It is just a small arc of darkness against the edge of the Sun. You cannot see it with the solar glasses right away, the Sun will still look like a ball. But give it a few seconds and the anomaly will begin to appear. It will slowly grow covering the solar disk over the next hour.

Over the next hour each time you check the Sun with a viewer a through a solar telescope, more and more of the Sun is covered by the Moon. For most this eclipsing process seems to take a lot longer than needed. Kind of like waiting for anything, time just runs slower when you watch it carefully. Should you have the ability to completely ignore the partial eclipse phase you will not really notice much until the Sun is about half covered. The temperature may start to dip and the light of the Sun is starting to seem odd. It is not as bright as it should be (on a clear sunny day). You will hear eclipse chasers remark about the temperature at some time. If you don't have a light shirt or cover up of some type, now is a good time to consider getting one. The eclipse is still half an hour away and that may seem like eternity to eclipse chasers, it really isn't and thus a good time to get ready for the next parts.

As the total eclipse draws near the eclipse chasers will caution others not to move or jump around, a buzz will start as people say they see darkening on the horizon to the West or they spot shadow bands. Shadow bands are waves of light and dark that sweep across the surface making seem as if the ground or a wall is vibrating in light. They are kind of hard to see if you are not at the right angle.

Venus and other brighter planets may become visible at this time. The sky takes on a darker blue color similar to a clear sunset. You should notice the air feeling cooler and maybe the wind settling down.

Second contact:

With just seconds remaining the buzz of noise from your group will increase until there is a scream of joy or amazement and others yell out second contact. My advice is to wait another couple seconds before looking at the eclipse. The diamond ring at second contact will flash blind you and cause spots to appear in your field of vision. Much like a bright flash camera going off in your face, and having that happen right at the start of totality is really poor timing.

Looking up at the eclipse is amazing. An eye in the sky, a bright flower with a dark center, an angel, the open yaw of a dragon falling on you from above, and much more have been used to try to describe the view.

It does not matter once you have seen one. You are now part of that special group.

After Totality:

You have lost your eclipse virginity and are no longer a groupie. Now you know. There is a good chance some of you just might become eclipse chasers.

After totality there will be a celebration and much discussion about what was just seen. Pictures will be compared and shared. And plans will begin in earnest about the next one. It seems strange, but most will ignore the eclipse ending. Watching the Moon slip away and the Sun grow can be a very sad for eclipse chasers. It means another eclipse is over and it will be a while before they can see that amazing thing in the sky again.

- Wishing you have clear sky above your head for the eclipse in August!