Archive for the 'Total Eclipses of the Sun' Category
As many of you have realized, there has been a significant drought of total solar eclipses in the USA for nearly 40 years, and not just in the USA, in all of North America. Eclipse chasers were spoiled in the 1970s with a total eclipse nearly every other year, then the drought of USA eclipse began. But now, at last, there is a light at the end of the tunnel, and the drought will soon end for millions of Americans who have never seen a total eclipse of the sun. On August 21st, 2017 (a Monday), the path of a great total solar eclipse will come ashore on the Pacific Coast just south of Portland, Oregon, and will progress eastward through the center of the country, exiting on the Atlantic Coast in South Carolina. It will pass over many large cities, including St. Louis, Nashville, Lincoln and Charleston on a fine summer day. This is a time of year when the USA cloud cover is near a minimum, thus it is likely that millions of Americans will experience their first total solar eclipse.
The prime spot along the path in terms of the duration of the eclipse will be near the Illinois/Kentucky border. How long will totality last? It depends upon where you observe. It will be one minute and 50 seconds in Oregon, two minutes and 44 seconds (the maximum) south of Carbondale, Illinois, and two minutes and 27 seconds in South Carolina. The brevity of a total eclipse may come as a shock to those who have never seen one, but the duration of such an eclipse is never more than 7 minutes and 30 seconds, with the average eclipse being about 3 minutes. Plus, as you will find out, those three minutes will seem to pass much faster than the time it takes you to cook a three-minute egg. It will be over in what seems like 45 seconds, so be ready with your tripod, camera, telescope and binoculars.
Where should you go to observe this? If you want to minimize travel time and distance, just plan to go to the point very near the central line of the path that passes the closest to your home area (consult the map of the path). You should also have two alternate locations that are a couple of hundred miles each way (east and west) from your primary point. This is in anticipation of clouds at your primary location. Watch the weather predictions for these three locations starting on Friday, August 18, and plan accordingly. if you want to experience an extra 25 to 54 seconds, plan to go to a spot on the centerline of the path between St. Louis, Missouri and Charleston, South Carolina. You will get 2 ½ minutes or more in that segment. A final word … stay mobile, watch the weather and don’t miss it!
Today we have the great advantage of knowing where and when they will occur well in advance. In the not so old days of the 1700s and the 1800s, expeditions used to be sent out six months in advance, with most having little luck because of poor map coordinates and poor predictions of the latitude, longitude and timing. But today, in the great field of predictions, the prediction of a total solar eclipse is probably among the most accurate that can be made. Unlike most other natural events such as earthquakes and volcanoes, and even weather, total solar eclipses can be predicted (or calculated backward in time) for thousands of years to within a fraction of a second. And you know for sure that it will occur as promised; there will be no delay or cancellation… it will occur right on time at the spots predicted. Modern astronomy, GPS systems, measurement accuracy of orbital elements and supercomputers have combined to allow super prediction accuracy. That is how a space probe to Saturn can be navigated through the ring after an eight-year voyage. What else in life has that degree of predictability? NASA has a book with detailed predictions of location and timing for every solar eclipse that will occur in the next thousand years. If you look in there and see that a total eclipse shadow is going to pass over your town in 873 years, you can rest assured that it will, even though you will not be there to see it!
With an eclipse of the sun occurring at least twice per year, why have so very few people seen a total solar eclipse? Well, for starters, most solar eclipses are not total, they are only partial, and many more people have seen a partial eclipse of the sun than have seen a total eclipse. There is another point that is perhaps the most important reason. A total eclipse of the sun is visible only within a narrow path on the earth that is 15 to 150 miles wide, whereas a partial eclipse is visible anywhere in a band more than 2000 miles wide. If you are not in that narrow strip of totality, you will not see a total eclipse. When the fact of a narrow strip is combined with the fact that the earth’s surface is 70% water, then most of the path of a total eclipse is over an ocean. Therefore, entire continents can go decades without a total solar eclipse. In fact, North America has gone since 1979 without one, and will not get another one until 2017. That means that hundreds of millions of Americans have never experienced one. Another factor is that the narrow path of totality can be anywhere on the earth, and that truly means anywhere! It can be in the Gobi desert (2008), Antarctica, in the southern Pacific not touching any continent, northern Greenland in winter, etc. Therefore they are not generally easy to get to … in fact they are almost always not. The rule of chasing total solar eclipses is that you have to go to them, they will not come to you. If you stand on a spot on the earth (such as your front yard) and wait for a total solar eclipse to come to you, you will wait (on the average) 700 years. Thus a contributing reason for people not seeing a total eclipse of the sun is that they do not chase them; most people wait for an eclipse to come to them. The final factor in having so few people who have actually experienced this phenomemom is the weather. If it is raining, or even just cloudy, you will not see it. A classic example is the July, 2009 eclipse over southern China. The path of totality went directly over Shanghai, where tens of millions would have seen their first total eclipse, but it was cloudy and raining at that exact time. Only small numbers actually saw part of it about 30 miles from Shanghai.
What is a total eclipse of the sun? Well, it is truly one of the most spectacular natural events that we can witness. In ancient times it was one of the few things that could stop armies in the midst of a battle. Some planning work (and expense) is usually required to get to the predicted narrow path of totality on the earth. If you do get to this predicted path, and the clouds cooperate, you will be rewarded with a two-hour spectacle that you will never forget, with the sun being gradually covered by the moon over a one-hour period, and then uncovered for another hour, with a spectacular period of a few minutes in the middle where the sun is totally covered. This produces a few minutes of “night” during the day. The darkness will come on rapidly as the sun is nearly covered,and strange sky colors that are not normally seen will be evident. The sky brightness will fade very rapidly, then return, as the last fraction of the sun is covered and then uncovered. When the sun is covered you will not need special glasses to view it. The birds will become silent and Venus and Mercury will pop out rather quickly as the sky becomes dark, and you will see a “sunset” line of red all around the horizon. You may see some bright stars and some moving shadow bands. When the sun bursts out again the birds will sing, and roosters will crow. It will all be over in just a matter of minutes, so don’t blink. Everyone should have the opportunity to observe this spectacle at least once during their lifetime. For detailed information on where, when and how to observe and photograph the upcoming great USA total eclipse of August 21, 2017, check out the pages on that eclipse at www.worldtravelreports.org/solar-eclipse-gallery-listing/upcoming-eclipses .