Win Free Eclipse Glasses!

This contest how now ended.  We are running a Facebook contest, and two lucky winners will receive a free pair of eclipse glasses.  The glasses are similar to the ones shown here, and are ISO and CE certified as safe for direct viewing of the sun.  They are made in the USA by American Paper Optics.  (I purchased them directly from American Paper Optics, and they were shipped to me directly, so there’s no chance that these are counterfeits.)

Most retailers have now run out of the glasses.  This might be your only chance to get them, and they won’t cost you a dime!

To enter, simply follow these two steps:

  1. “Like” us on Facebook. Just click on this link and then click the “Like” button near top of the page.  (If it says “Liked,” then you already have this step taken care of.)
  2. Go to the contest announcement, which is the pinned post at the top of that page. I have randomly generated a number between 1 and 200. Post your guess as a comment to that Facebook post.  The two closest guesses will be the winners. I will contact the winners for their mailing addresses.

The winners will be the two who posted the numbers closest to the secret number.  In case of tie, the earliest post(s) will win.

The contest ends at 11:59 PM Central Time on Monday, August 14, 2017.  I will contact the winners by Facebook message, and you will need to send me your mailing address.  I will mail them by First Class Mail on Tuesday, August 15.  Glasses will be sent folded in a normal business size envelope.

If you want to purchase eclipse glasses, please see my post with advice on where to find the few remaining pairs.  Click here for more eclipse information.

The Dark Side of Sunspot Cycle 19

1967AugRadioElecSixty years ago, solar activity was at an all-time high, and the sun was plastered with sunspots. This was good news for hams, who depend on this solar activity for ideal radio communications on the high frequency bands. But in addition to being literal dark spots, this was, figuratively a dark time for the hapless TV repairman in fringe areas, because it fell upon him to explain to his customers that their interference woes weren’t his fault, but were instead caused by blotches on the sun.

Fortunately, the TV repairman got some sympathetic advice from this article in the August 1957 issue of Radio Electronics.

It starts by noting that Sunspot Cycle 19 was about to reach a peak, which was good news for hams and shortwave listeners, for whom shortwave propagation would be better than at any other time in history.

But the average TV owner “probably does not care about receiving Havana, Cuba, or some other distant TV station over his favorite local channel,” which was a distinct possibility in fringe areas. The article noted that this would be particularly an issue for channels 2, 3, and 4.

The article counseled the serviceman on how to deal with these calls. And unfortunately, there was little that could be done, other than to “explain to the owner what is happeninng and that the condition will probably pass in a short while. Ask him to call the next day if the trouble is still there.”

The article suggested that a good way to educate the customer would be to draw a sketch of the earth and ionosphere as shown above. While reorienting the antenna might help in some cases, the best advice was to hope that the owner understood what was happening. If the customer understood, it would make him “less likely to call a service technician and thereby leave the technician more time to devote to true television troubles.”

 



Alternatives to Eclipse Glasses

This page last updated Thursday, August 17.  It is now too late to get the glasses, but I list a number of alternatives that will work better.

Quick Links:

In most areas, it is now too late to get eclipse glasses at a reasonable price.  Just like happened during a recent eclipse in England, the glasses are now unavailable in most places.  They might be available in some areas at a reasonable price.  But don’t pay more than a few dollars, because you don’t need them.  If you don’t have them, don’t worry.  You can actually get a better view using other methods.

Whatever you do, don’t spend hundreds of dollars trying to find a pair.  They’re nice to have, but they are not essential.  You do have alternatives.   First of all, if you are around other people watching the eclipse, you can probably just borrow theirs.   You’ll only look through the glasses for a minute or two at a time.  Several people can use the same pair.

If you don’t have glasses (or even if you do, and want a better view, you can use a method of indirect viewing.

You can make a simple pinhole viewer, and instructions are available at the NASA website.  Many other variations are available, and you can get a  good view of the sun projected on a screen.

 

 

Other projection methods provide a view that is better than the eclipse glasses.  One extremely simple method uses binoculars or a small telescope or monocular.  (Use cheap binoculars, since the sun might overheat and damage them. Even toy binoculars like the ones shown here should work just fine.)  You do not look through the binoculars.  Instead, you point one end at the sun, and the other end at a white screen, or even the wall of a building.  You will see a very detailed image of the sun on the screen.  It’s amazingly simple, and you will see a much better view than you would with eclipse glasses.  It is described at this website.

Also, remember that eclipse glasses can be shared.  It’s somewhat interesting to look at the crescent sun, but most people will only look for a few seconds, and then possibly look again later when it’s gotten smaller.  In the meantime, others can use them.  If you are traveling to some kind of viewing event, it’s likely that other people will let you borrow their glasses.

 


Buying Online

Glasses are no longer available.  This page has been continually updated.  All of the websites listed below had glasses at a reasonable price.  As each one ran out, I removed the listing, and now it’s too late.

The following suppliers were previously listed here, but are now sold out:  American Paper Optics AmericanEclipseGlasses.comGreatAmericanEclipse.com and  Rainbow Symphony.  The GreatAmericanEclipse.com website remains an excellent source of information about the eclipse.  At this point, I do not recommend ordering from  Amazon, eBay, or other similar sites.  You will pay too much, they might not arrive in time, and the product might not be safe.


Local Retailers in Minnesota and Other Areas

Glasses are no longer available.  This page has been continually updated.  All of the stores listed below had glasses at a reasonable price.  As each one ran out, I removed the listing, and now it’s too late.  In some parts of the country, the situation might be different, and you might want to check some of these stores in your area.  In many cases, the link is to the particular set of glasses sold by that store.

The following retailers had glasses, but are now almost certainly sold out:  New York:  B&H Photo and Video.  Minnesota:  Radio City in Mounds View , Toys R Us,  Lowe’s, Walmart, AxMan SurplusGirl Scout Shop in St. PaulBest Buy .

Some public libraries were giving the glasses away free.  They are probably gone by now, but they might have some available at special viewing events.

 

 



1942 Mallory Wood Condensers

1942AugServiceWith wartime material shortages, replacement radio parts were hard to come by. And even when parts were available, the manufacturers had to adapt to wartime conditions.

This is illustrated by this ad from the August 1942 issue of Service magazine, showing the Mallory “Wood Neck” condenser (what we would call a capacitor these days).  Instead of an aluminum case and base, the capacitor had an impregnated paper case and a threaded wooden base.  The ad noted that “they are designed for the emergency but we predict they will be popular long afterwards.”



Science Fair Idea: How to Weigh Smoke

1937AugPS

Sir Walter Ralegh by 'H' monogrammist.jpg

Sir Walter Raleigh. Wikipedia image.

Sir Walter Raleigh is reputed to have won a bet with Queen Elizabeth that he would be able to weigh the smoke coming from his pipe. After she accepted the bet, he weighed a pinch of tobacco, smoked it, and then weighed the resulting ashes. He convinced the Queen that the difference in weight was the weight of the smoke.

Of course, the Queen could have won the bet by pointing out that the combustion products contained oxygen, and most of that oxygen originated not in the tobacco, but in the air. But she didn’t think of that, and instead paid the bet.

This little experiment, from 80 years ago, takes into account the amount of oxygen, and proves that the total mass doesn’t change during the combustion process. You do this by placing some matches inside a sealed glass flask. You carefully place it on a balance. Since the matches are sealed inside, you’re not able to strike them. To ignite them, you heat up the outside of the glass. Eventually, the matches will burst into flame and burn until all of the oxygen in the flask is consumed.

The balance won’t move, since the weight inside the container remains exactly the same. The weight of the matches plus the oxygen will exactly equal the weight of the burnt matches plus the weight of the smoke. Since it’s all sealed inside the same container, that weight won’t change.

If you wanted, you could take it a step further and repeat the experiment with the flask open.  In this case, the matches would burn longer.  Oxygen would be able to go in, and the smoke would be able to go out.  Therefore, the weight would change.  Would it go up or down?

You can easily adapt this idea to your next science fair assignment with a hypothesis along the lines of, “mass is conserved during combustion.”  While that other kid is busy fumbling with the paper mache volcano, the teacher will be suitably impressed that you’re smarter than Sir Walter Raleigh, and you’ll undoubtedly go home with the first prize.

The photo and experiment appeared in the August 1937 issue of Popular Science.



1917 Wireless Telegraph

1917JulyElectExpWirelessTelegraph

We’ve carried plans for other wireless telegraphs and telephones that relied upon ground conductivity, and here’s another one that comes from a hundred years ago this month, in the July 1917 issue of Electrical Experimenter.

This one is a bit mysterious for a couple of reasons.   First of all, the receiver appears to contain a crystal detector wired in series. (At least I think that’s what the component to the left of the capacitor is.) Admittedly, I haven’t tried making one of these, but I can’t really see the purpose of it, since the signal transmitted through the ground is essentially an AF signal that the headphones would be able to pick up.

Second, I can’t see any real advantage in burying one of the ground electrodes so deep (10 feet). Doing so does achieve 9 feet of separation between the two grounds, and this separation is necessary. But it seems to me that this could be accomplished much more easily by placing both grounds near the surface, separated horizontally. This would avoid the necessity of having to dig a 10 foot hole, which seems like a lot of work.

Finally, I can’t think of any good reason for making one electrode copper and the other zinc.

The accompanying text doesn’t answer any of these mysteries. The diagram was submitted by a reader, one O.M. Warren of Detroit, MI, who submitted it along with the question, “would it be possible to use the following scheme to telegraph a distance of a block or two?”

The editors answered merely: “Yes. You will have no trouble in transmitting considerably more than the distance you mention.” But they don’t even hint that Mr. Warren needn’t bother digging the two ten foot holes.

The reader also asked whether a tuning coil or loose coupler should be used, but the editors did say that they should not be used, since “it is impossible to tune any distant signal with this ground telegraph system, speaking generally.”

But since radio transmission or reception were forbidden during the war, Mr. Warren would be able to communicate.  Let’s hope that nobody told him his ten foot holes were unnecessary.



Think It Over, 1942

BC072742

This RCA ad, which appeared 75 years ago in the July 27, 1942, issue of Broadcasting, shows the warning label affixed to radios in Nazi Germany.  It contains this warning:

Think it over. Receiving foreign broadcasts is a crime against the German State. By order of the Fuehrer, it will be severely punished.”

The ad goes goes on to say that most will think it over. And perhaps, like a sensible Nazi subject, the radio’s owner will take the warning to heart.

And maybe you don’t. Maybe there’s a hunger for truth in you, that no threats can suppress. Maybe you still retain some sense of the inalienable rights of a decent human being.

Maybe you tune in far-off America: to RCA-NBC International Shortwave Stations WRCA and WNBI, hearing truths that are flashes of light in a world of darkness and despair.



Tips for Eclipse Camping Newbies

Path of Totality. NASA image.

Path of Totality. NASA image.

If you recently decided to travel to view the eclipse on August 21, you might have first checked to see if there were any hotels inside or close to the area of totality.  When you did, you probably discovered that there are none, or they would cost hundreds or thousands of dollars.  In many areas, the only option, if you need to stay overnight, is to camp.  Fortunately, many temporary campgrounds, some with very reasonable prices, have sprung up from Oregon to South Carolina.  I have a listing of many of these campsites.  Wherever you will be viewing the eclipse, it’s likely that you will be able to reserve a campsite in advance, and knowing that you have a safe place to stay Sunday night will relieve much of the stress.

 


Quick Links


 

stelprdb5325060If you have experience camping, then you probably won’t learn anything new from this page.  This page is devoted to the newbie who has never been camping before.  You’re going camping this time only because you have no other options.  There’s nothing wrong with that, and with a little bit of preparation, you’ll have a pleasant experience Sunday night, and you’ll get a good night’s sleep the night before the eclipse.  I’m an Eagle Scout, and my family regularly goes camping, so I might be considered an “expert.”  But it’s not necessary to be an expert to enjoy a short camping experience.  On this page, I show the preparations that are necessary for the newbie to have a pleasant camping experience.

In many of the areas I’ve checked,it will be possible to get a hotel room on Monday night, the night after the eclipse.  By then, most chasers will be headed home.  So even if you need to stay a second night at your eclipse viewing location, or stay overnight on the drive home, you’ll probably only need to camp one night, Sunday night.  On the other hand, some areas might be so congested that it will be best to arrive Saturday and wait until Tuesday before starting home.  Even if you need to camp two or three nights, the advice on this page should get you through the adventure.

You will need to go out and buy some stuff.  If you walk into your local outdoor store and tell them that you need to outfit yourself for camping for the first time, the salesperson will see dollar signs and offer to sell you expensive deluxe equipment.  While it would be nice to spend hundreds or thousands of dollars for the best equipment, it’s not necessary.  On this page, I have some recommendations of some of the things you might need.  Nothing on this page is the deluxe version.  Most of these recommendations are for the bare minimum cheap version of the various products.  But for one or two nights, they will prove adequate.  In many cases, the expensive versions are more durable and will last many years.  But for one use, the cheap versions will usually be just as good.


Tents

The first consideration is to decide whether you will actually need a tent.  Depending on what kind of car you have, it might work just as well to sleep in your car.  Trying to sleep while sitting on one of the seats, even if it reclines, usually doesn’t work very well.  There’s a reason why humans lie down to sleep, and they’ve done this for millions of years.  But if your vehicle has a flat surface long enough for you to lie down, then sleeping in the car might be the best option.  If your vehicle is wide enough, you might be able to stretch out on the back seat.  In a van or SUV, there might be enough room on the floor.  In a hatchback, if the back seats fold down, then you can sleep in the back.  The only way to find out for sure is to crawl in there and see if you can lie down.

If you do decide to sleep in your car, remember that it will get hot in there, so you’ll need to roll down some or all of the windows.  Therefore, you will need some kind of screen to cover them to keep the bugs out.

If you can’t find a large enough flat surface in your car, then you probably want to get a tent, and this will be your first purchase.  The most important advice about tents is:  Practice setting it up at home!  Most tents are relatively easy to set up, but there’s always a learning curve.  And every tent is different.  While you’re still at home, you want to make sure you know how to set it up, and that no parts are missing.  In campgrounds, I’ve witnessed many unhappy couples taking out a brand new tent and then realizing to their horror that they don’t know how to set it up.  If they had practiced a couple of times at home, they would have saved themselves a huge amount of frustration and stress.

When shopping for a tent, you will see that they are marked with how many persons they sleep.  However, almost without fail, these numbers are the absolutely maximum number of people you could possibly squeeze in.  So for a “two person” tent, yes, you could cram in two people if you really had to.  But it would be a lot more comfortable with just one person.  So if you really have two people, then you would probably be better off with a three or four person tent, even for just one night.

Normally, I have an important piece of advice when shopping for a tent.  That advice is to get a tent that you can stand up in.  If you’re going to be camping regularly, this is extremely important.  At home, when you get out of bed, you stand up.  Right before you get in bed, you are standing up. When you change your clothes, you stand up.  You don’t normally notice it, but the sleeping process involves a lot of standing.  So normally, I recommend getting a tent that allows you to stand up.  It really makes camping a lot more pleasant.

Unfortunately, however, the cost of tents gets exponentially higher when you get one big enough to stand up in.  If you’re really getting a tent that you’re only going to use once, you’ll save a lot of money by getting a smaller one.  And the smaller tent will also be a lot easier to set up.  So in this case, I’ll modify my normal advice.  It’s annoying having to crawl around on the ground while you get in bed.  It’s annoying having to change your clothes while crawling around.  But it’s also only one night, and you want to save money.

With that in mind, a tent similar to the one shown here is my recommendation for one person.  Two people could probably squeeze in, but it wouldn’t be particularly comfortable.  The primary advantage of this tent, the Stansport Scout Backpack Tent, is that it is cheap.  It is also lightweight and won’t take up much space in your car.

The other big advantage, though, is that it’s easy to set up.  As you can see, the A-frame style of this kind of tent is very “old school.”  It doesn’t look futuristic like many of the dome tents that you see.  However, in my experience, the dome tents are harder to set up, and they often require two people.  (Dome tents, however, have the advantage of not needing stakes in the ground, although they are usually highly recommended.  With the inexpensive A-frame tent shown here, the stakes are absolutely necessary.)  Dome tents are harder to set up because the poles have to go in just the right spot.  Also, the poles need to be just the right size and shape.  If you break one of the poles for a dome tent, it’s usually easiest just to throw the tent away.  With this type of tent, if you break a pole, you can improvise and just use a stick of about the right size.

Setting up this kind of tent is very easy.  First, you just pound in a stake in each corner to hold the floor tight to the ground.  (It’s a good idea to bring along a hammer for this purpose.)  Then, you pound in a stake about 3 feet in front, and about 3 feet behind.  You put in the poles, and then you run a rope from the top of the pole to the stake.  Finally, you put in two more stakes on the side, and run ropes to hold the side walls out.  It really only takes about 5 minutes.

If you have more than two people, then you really do need to move into the “dome” tent category and get something like the one shown here, the “three person” Wenzel Alpine Tent.  Even though it’s billed as “three person,” it’s really only suitable for two.  It’s still quite inexpensive.  It is harder to set up, and you’ll definitely want to practice at home.  The setup really requires two people, since it’s usually necessary to have one person hold a pole in place while the other person inserts it in the correct spot.  Poles have to be put up in a certain order, and you will need to read the directions.  It’s not particularly difficult, but you will need to practice at home.

The “six person” tent shown here, Coleman Evanston Screened Tent, is still relatively inexpensive, and would be a good choice for two adults and two or three children.  An 8-person version is also available.  At this point, the tent is getting large enough so that you can stand up in it.  Even if you have to stoop over a little bit, being able to stand makes it a much more pleasant experience.  This larger tent is also more complicated to set up, so you’ll definitely want to practice at home.

Sleeping Pads

The ground is hard!  The floor of your car is hard!  Your camping experience will be infinitely more comfortable if you have something soft to sleep on.  You have a number of choices.

If you’re getting a large tent, then you might consider getting a cot to sleep on.  A cot is infinitely more comfortable than the ground.  If there’s room and it’s in your budget, then you might consider getting one like the one shown here.  But if you have a smaller tent, or want to economize, then the other option is to get some kind of soft object to sleep on.  You can chose between some kind of foam pad, or an air mattress.

Foam pads are somewhat more convenient, but they are mostly designed to insulate you from the ground.  While they are softer than the ground, they’re not particularly comfortable to sleep on.  Therefore, my personal preference is an air mattress.

If you know for sure that this will be your only time camping, then you might want to simply get a cheap air mattress like the one shown here.  These are most commonly used at a swimming pool, but there’s no reason why you can’t sleep on one.  Eventually, it will spring a leak, but in the meantime, it will make your sleep more comfortable.  These also have the advantage of being inflated with lung power, so you won’t need to buy a special pump.

You can also get an air mattress designed for sleeping, such as the one shown on the right.  These are very comfortable, and it will feel like sleeping on a normal bed.  They are relatively inexpensive, but they do require a pump to fill them up.  You can get a  pump that is battery operated or one that plugs into your car.  (Note:  even If you have a compressor for putting air in your car tires, it will not work for filling the air mattress.)

Sleeping Bag

The eclipse will take place on August 21, and whether you are in Oregon or South Carolina, it will probably be hot.  So you don’t need to worry much about a sleeping bag.  In fact, you might want to just bring normal sheets and blankets from home.  But if you do want one, a cheap sleeping bag like the one shown here will be more than adequate.

One thing to keep in mind about cheap sleeping bags is that there’s a possibility that they won’t survive one washing.  Washing them might result in the insulating layer getting messed up.  They’re great until the first washing, though.  Therefore, resist the temptation to wash the sleeping bag before using it, not that it would be necessary.  When you get home, you can take your chances and throw it in the washing machine.  If it survives, great.  If it doesn’t, you already have your money’s worth from it.

Cooking and Eating

If you’re going to be camping out West, then there’s a major fire danger, and it’s likely that you will not be able to have a fire or even a charcoal grill.  You might consider buying a propane stove, but you’ll only be camping for one or two days.  I would recommend just getting a cheap cooler.  You can buy disposable styrofoam coolers like the one shown here at most supermarkets.  Just fill it with ice and pack food that you can eat without cooking.

Whatever kind of cooler you use, you will find that it’s very helpful to have a large supply of Ziploc bags.  The ice will melt, and no matter how careful you are, the items inside will be floating in water.  If you pack everything in sealed plastic bags, then you won’t have to worry about it.

Don’t forget to bring utensils, paper plates, cups, napkins, etc.  There’s no need to purchase special “camping” versions of these items, since the ones you have at home will work perfectly well.  Buying a large assortment of plastic silverware will mean that you don’t have to worry about washing dishes.  And don’t forget garbage bags.  It’s possible that the dumpster of your temporary campground will be overflowing, in which case you might need to take home your own trash.  Having good trash bags with you will make the process much more pleasant.

Portable Toilets

Normally, if you go camping to a state park or private campground, you don’t have to worry about where to go to the bathroom.  There will be a restroom within convenient walking distance of your site.  However, for the eclipse, thousands of people will be camping in temporary campsites.  Hopefully, the owners have rented enough toilets to accommodate everyone.  But there’s a distinct possibility that some of them have underestimated the need.  And if you’re stuck in traffic, or parked at a remote location waiting for the eclipse, there might not be a restroom nearby.  Fortunately, you can bring your own from home!

Shown here is the Passport Potty from Sanitation Equipment.  It’s relatively inexpensive, but when you need it, it’s worth its weight in gold.  It would fit inside a family-size tent.  And unless you a driving a compact car, there’s probably enough floor space in most vehicles to have it there. A very similar model available at Walmart at this linkicon. You can order online, and then pick it up at the store the same day.

To use it, you go as you would with any other toilet.  To “flush,” you open a valve at the bottom, and rinse the bowl with the built-in water pump.  You then close the valve, and the contents are hermetically sealed into the compartment below.  Spray a shot of Febreeze into the air, and the crisis is over!  Especially if you have young kids, owning one of these can be a lifesaver.  No eclipse chasing vehicle is complete without one!

If you buy one of these, you will need to buy some of the chemical to put in the tank, which is quite inexpensive.  I prefer the pouches of dry chemical, but it’s less expensive to buy a bottle of the liquid chemical, since you only need a very small amount.  Of course, you will also need toilet paper.  While not absolutely necessary, it’s best to use the special RV toilet paper, since it breaks down faster and makes the emptying process easier. You can also buy the toilet chemicals iconand toilet paper  at Walmart. You can order online, and then pick them up at the store the same day.

When you get home, or when you get to the first flush toilet of your voyage home, it’s a relatively simple matter to empty the toilet.  However, this is one area where it’s best to practice at home.  Fill the toilet with clean water and practice emptying it a few times.  After a few tries, you will be able to do it confidently and without spilling.  While you are camping, hand washing facilities might not be available.  So it’s a good idea to pack some hand sanitizer.

Flashlights


In order for there to be an eclipse, there needs to be a new moon.  And if you’ve been careful picking out your eclipse camping spot, you picked a spot without street lights.  This means that the night before the eclipse, it’s going to be dark.  When the sun goes down, you won’t be able to see anything.  You can probably fumble around with your cell phone and get a little bit of light, or you can even annoy your camping neighbors by turning on your headlights.  But life will be a lot easier if you bring along some flashlights.  The flashlights shown here are inexpensive, they’re durable, and they work well.  Bring along a few more than you need, along with plenty of extra batteries.

There’s also a good possibility that you won’t have cell service or that the network will be overloaded.  Therefore, it’s a good idea to also bring a good portable radio for receiving weather and traffic information.  One good option would be this radio, which pulls in NOAA weather broadcasts in addition to normal AM and FM stations.  It also features a hand crank, which means that you can continue listening to it even if the batteries go dead.


 

If you have the basics listed above, you’ll survive your camping adventure and actually enjoy it!  Since local stores and restaurants won’t be able to keep up with the demand, bring your own food and water from home.  Enjoy your adventure!

 

 

 

 



Take Your Kids to See the Eclipse!

If it’s humanly possible, take your kids to see the eclipse on August 21!

National Park Service.

National Park Service.

My first awareness of the concept of a solar eclipse came with the total eclipse of March 7, 1970.  On that Saturday, the sun darkened in the Pacific, and the shadow of the moon raced over southern Mexico before entering the Gulf of Mexico.

Then, it hit the United States of America, with its shadow first hitting Florida, then Georgia, then the Carolinas and Virginia, then grazing Maryland before heading back out to sea, saying goodbye to the United States at Nantucket.

For those with Learjets, it then crossed Nova Scotia, Newfoundland, and the French island of Miquelon, before heading out to sea again into the North Atlantic.

Where I was in Minnesota, it only covered 47% of the sun at high noon. If nobody had told me about it, I wouldn’t have even noticed. It didn’t get dark outside, and no animals were confused. But that day, it was the biggest deal in the world. The moon contained fresh footprints of Americans who had walked on its surface less than a year before. Now that same moon was casting its shadow over me.

To me and my fellow third graders, it was presented as a big deal. And it was a big deal. If there had ever been any doubt about it, yes, the moon went around the earth, the earth went around the sun, and sometimes they got in the way of each other. Any third grader could see tangible proof.

In school, we had learned all about umbras and penumbras, and by the time the big day came, I was an expert on all things eclipse. With a shoebox, some foil, and a note card, I constructed myself a pinhole viewer. I figured that if a pinhole was good, then a giant hole would be even better. Fortunately, my mom corrected my error and got the viewer in good working order.

I pointed the box at the sun coming in the window, and sure enough, there was a little crescent shape of sunlight coming in through the round hole, plainly visible on the note card.

Perhaps I was a little disappointed at the tiny size of the image, but it didn’t matter. Right there in my shoebox was proof positive that the moon orbits the earth.  I didn’t have to take anyone else’s word for it.  The proof was right before my eyes.

We turned on the TV, and we saw the darkened skies and the amazed reactions of those who went outside to see it. I don’t remember too many details about the TV coverage. Mostly, I remember some poor confused rooster in Florida or Georgia crowing in the middle of the day.

When we got back to school the next Monday, the eclipse was the topic of conversation. We knew how the universe worked, because we had seen it with our own eyes. It was a big deal, and the kids remembered it.

In 1970, we were over a thousand miles away from the path of totality, and going to see it wasn’t really an option. But I envied those people and roosters on TV who got to see it in person.

Nine years later, another eclipse came to North America. On February 26, 1979, the eclipse started in the Pacific Northwest, darkened most of Montana, and grazed our neighboring state of North Dakota before making a spectacular show for humans and roosters alike in Winnipeg, Manitoba, tantalizingly close to Minnesota. I wanted to go to Winnipeg, but circumstances didn’t permit it. So I had to stay home and watch the 90% coverage. I had a telescope, complete with a solar filter that screwed to the eyepiece. In retrospect, that solar filter was horribly dangerous. The heat of the magnified rays of the sun could have cracked it, sending those same magnified rays right into my retina.

I got lucky, my retina survived, and I saw another eclipse. But it didn’t get dark outside. I didn’t hear any roosters. I was close, but I didn’t really see it. They said that it wouldn’t happen again until 2017, which sounded like an eternity to wait. But I vowed that I was going to go see it.

I’ve seen a couple other eclipses since then. I even drove to Springfield, Illinois, to get right in the middle of the path of the annular eclipse of May 10, 1994.  My pinhole viewer revealed a tiny ring as the annular eclipse reached its peak. But it wasn’t dark, there were no roosters, and as far as I could tell, the citizens of Springfield didn’t even bother to come outside to see it, despite being right in the middle of the path.

By now, I was already convinced of the celestial mechanics. It was mildly interesting, but like the residents of Springfield apparently concluded, it wasn’t that big a deal.

The upcoming eclipse of August 21 is a big deal. It’s certainly a bigger deal than the one in 1994, because it’s actually going to get dark, and roosters will crow about it, just like they did in 1970 in Florida and 1979 in Winnipeg.

But it’s a much bigger deal than the one in 1970. In 1970, it wasn’t realistically possible for a family in Minnesota to go to Florida to witness it. That’s not true this time. Because the path of the eclipse so conveniently crosses the country from Pacific to Atlantic, the majority of Americans live within a one-day drive. For those of us in Minnesota, it means driving to Nebraska or Missouri. That is something that most families are capable of doing. You don’t need a Learjet. You don’t need to cross an international border. You don’t even need to drive to the other side of the country. All you need to do is drive to Nebraska.

Your kids never got to see men walking on the moon.  They never even got a chance to see the Space Shuttle being launched.  They’re vaguely aware of the International Space Station, but they don’t know the names of the two Americans and one Russian who are currently aboard.  We know the names Armstrong, Aldrin, and Collins.  But they don’t know the names Fisher, Yurchikhin, and Wilson.  The wonder is seemingly gone.

On August 21, the wonder will be back.  Those footprints are still up there on the moon, and that moon is going to cast a shadow over the Great Plains.  Americans can’t go to the moon any more.  But Americans–including your kids–can go see the shadow of that moon darken one of your neighboring states.  You don’t need a Learjet; you don’t need to go to another country.  You can probably get there on one tank of gas.

If you are in Minnesota or Iowa, I’ve already done the planning for you.  You can drive to Nebraska on Sunday, stay in an inexpensive motel or camp that night, drive a few miles on Monday to see the eclipse, and get home Monday night.  You can probably do it for a hundred bucks.  If you live somewhere else, then you’ll have to do the planning yourself.  But wherever you are in the 48 states, you are probably within one day’s drive.  You should go.

If you go, your kids will see it get dark at noon, and if there are any roosters around, they’ll be able to hear them.  If you go, the flat earthers will never stand a chance of misleading your kids.  Your kids will know how the universe works, because they will have seen it with their own eyes.  The wonder will be back.

In Minnesota, school is not yet in session, so your kids won’t even miss school.  You’ll probably need to take a day off from work, but don’t you think it’s worth it?

LunarEclipseFromFlatEarth

Lunar eclipse as viewed from the flat earth. Keep them inside so they don’t see this!

If you live somewhere where school is in session, then it would be nice to think that the schools will take care of educating your children.  But don’t count on it.  During a recent eclipse in Britain, some schools kept the kids inside, with the blinds closed, during the eclipse.   The kids watched it on TV, and apparently have to take the TV’s word for it that the earth isn’t flat.

Some American schools seem to be taking the same approach.  Take, for example, the case of Shawnee Mission, Kansas, located only about 10 miles from the path of totality.  School will be in session on August 21.  If I were in charge, there would only be one logical thing to do.  If I’m an educator, then my duty is to educate the kids.  And there is only one logical way to do that–put the kids on a school bus and drive them the 10 miles so that they can see the sky go dark and hear that confused rooster crow.  But that’s not what they’re doing.  They’ll close the curtains and watch it on the internet.  “Some schools even plan to reschedule outdoor recess to avoid being outside during the eclipse.”  The kids will just have to take the internet’s word for it that the earth isn’t flat.  They won’t be allowed to see for themselves.

Fortunately, some schools deserve praise for proactively making sure that their students get to experience the total eclipse.  For example, the Parkway School District near St. Louis discovered that one of its schools was outside the path of totality.  So they made the wise decision to bus those kids to one of the neighboring schools that will experience totality.

One school that deserves particular praise is Lewis Central Middle School in Council Bluffs, Iowa.  Even though school won’t even be in session yet, the science teachers there took it upon themselves to organize a summer field trip a hundred miles away to Beatrice, Nebraska, to view the eclipse.

Unfortunately, however, these educators who actually decide to educate the kids seem to be the exceptions.  If school is in session, don’t take it for granted that the teachers will be proactive about allowing kids to have a sense of wonder about the universe.  Like in Britain or in Shawnee Mission, Kansas, there’s a distinct possibility that your kids will be locked in a  room with the blinds closed where they’ll watch it on the internet.  And that would be a shame.  Your kids deserve the chance to see for themselves that the earth isn’t flat.  They shouldn’t have to take the internet’s word for it.

If you decide to go, and you should:



1957 Two Tube Junkbox Special Broadcast Receiver

1957JulPEpictorialSixty years ago, the July 1957 issue of Popular Electronics showed how to put together this simple two tube broadcast receiver using junkbox parts.

The AC-DC set used a 35W4 rectifier, and the 12AT7 dual triode served as detector and audio amplifier to drive the speaker.  The author reported that it pulled in many local stations, and up to 500 miles at night.

The article warned that the AC-DC chassis should be kept clear of pipes and other grounded objects.

1957JulPEchematic