By Professor Guy Q. Publix
Sky gazers in the United States are entering a remarkable period within the next 33 years. There will be three total solar eclipses which will be visible to potentially millions of Americans. These three events will occur on Aug. 21, 2017, April 8, 2024, and Aug. 12, 2045. Professor Guy will outline some of the basic technical astronomical terms of total solar eclipses, but will focus mainly on those regions which will be fortunate enough to the view one of nature’s grandest spectacles.
Solar eclipses can only occur at the time of a new moon. That is the point at which the Moon moves between the Earth and the Sun, and from the Earth’s perspective, the disk of the Moon is dark because the sunlight is illuminating the Moon’s opposite side. As we all know, most new moons do not produce a solar eclipse for reasons I shall soon explain — in fact, widespread solar eclipses are rare. Some regions of the Earth may go hundreds of years without observing a total eclipse.
When a total eclipse does occur, however, the shadow of the Moon obscures the light from the Sun totally. Total obscuration may last only a second, or in rare cases of favorable geometrical alignments, up to just under eight minutes. In the middle of a sunny day the Sun will slowly grow fainter as the shadow of the Moon’s disc blocks more and more of the Sun’s surface. The entire eclipse process normally takes close to three hours.
Most of us have seen partial solar eclipses where the sunlight dims, but even this phenomenon pales (pun intended) in comparison to the limited areas which see the total eclipse.
On Aug. 21, 2017, the Sun will be more than 90% obscured in all of southern Missouri, and north central and northeastern Arkansas. This approximates the magnitude of sunlight received on Mars. But in areas of central, east-central and northwestern Missouri, the eclipse will be total. Some cities and towns in Missouri which will see total obscuration lasting approximately two minutes are St. Joseph, Columbia, Jefferson City, Sullivan, and Festus. Even north Kansas City and suburbs and south and southwest St. Louis County will observe a few seconds to over a minute of total eclipse.
In areas where the eclipse is total, the sky will be as dark as midnight. The stars will be fully visible, the birds will be roosting in their nests, and the temperature will drop several degrees. Where the Sun was, there will be a faint glow of reflected eerie light which comes from the Sun’s outer corona. Of course, this happens only in areas with clear skies. But even if it there is heavy cloud cover, it will be a disquieting sight to see it turn totally dark around 2:00 p.m. CDT.
Weather conditions in Missouri at this time of year are likely to consist of scattered cumulus clouds, and much of the state will see only widely scattered thunder storms which would mar the event for observers. So let’s begin the party preparations now.
The GE (Greatest time extent of the Sun’s obscuration) will take place about 95 miles northwest of Nashville – just west of Hopkinsville, Kentucky. Thus if you can snag a hotel room or RV site in Clarksville, TN or the northern Nashville suburbs, weather permitting of course, you’ll be in for the best show of the event. Then the next day which will be a Tuesday, you can take in the Grand Ole Opry.
By following the eclipse path provided by NASA (National Aeronautics and Space Administration) and the accompanying Google Map provided by astrophysicist Fred Espenak and NASA colleagues, you will observe that the total eclipse path will start in northern Oregon and arc in an east-southeasterly direction all the way through central Missouri southeastward through Nashville down though central and eastern South Carolina. To view the NASA map for 2017, go Here. The Espenak map will allow you to zoom to locations all along the path and let you click in and near the total eclipse path which is the path of the umbra (the Moon dark shadow) crossing the United States. For locations outside this track you can also left click to find out the percentage of obscuration of the partial eclipse. The path of totality is just approximately 70 miles wide but the area of North America which will see at least a partial eclipse (The penumbra-the Moon’s fainter outer shadow) is more than 3,000 miles across. For a brief biography of the renowned astrophysicist Fred Espenak click Here. There are many people who will have an opportunity to see this spectacular event. About the surest place of finding dry, cloudless weather will be in Oregon. This it its dry season, and Salem, Oregon will see totality.
Solar Eclipse 101 Basics
The Moon orbits the Earth in an elliptical orbit — thus the Moon is closer to the Earth at certain times and appears larger. The Earth also orbits the Sun in an elliptical orbit. This path is known as the ecliptic. The Earth-Sun distance varies from about 91.5 million miles at perihelion (the nearest point of the Earth’s proximity to the Sun which occurs in early January) to about 94.0 million miles at aphelion (the farthest orbital distance from the Sun which occurs in early July) The Moon’s orbit around the Earth is tilted at an angle of slightly more than 5 degrees to the Earth’s path around the Sun. This tilt usually results in the Moon’s shadow missing the Sun just to the north or south at new moon — the point at which the Sun, Moon and Earth are lined up, which is known as conjunction. This is why there are not solar eclipses at each new moon.
Total eclipses covering large portions of the Earth are rare. To have a total eclipse where the Moon’s umbra obscures or (occults) the Sun for the longest possible time occurs only when the Moon is orbiting the Earth at it closet point (perigee) AND the Earth is farthest from the Sun. Long duration total eclipses are more likely to occur in June, July and August at a time when the Moon is also crossing the ecliptic.
On April 8, 2024, there will be a second, somewhat larger solar eclipse which will pass directly over Hill ’n Holler land. Thayer, Mo., will have the Sun’s surface covered for 3:59 minutes; Mammoth Spring’s totality will be two seconds longer, while southwestern Randolph County, Ark., will experience the total eclipse for approximately 4:12 minutes. To view the NASA map for 2024, click Here.
The April 2024 total eclipse event will traverse an even more heavily populated section of the United States. The path of totality will run in a northeasterly direction from Mexico into southeastern Canada.
The GE will be near Durango, Mexico – lasting approximately 4:28 minutes. Major cities experiencing significant totality will be Austin, and Dallas-Fort Worth, TX; Little Rock, AR, Indianapolis, IN; Dayton and Toledo and Cleveland, OH; Kingston and Hamilton, ON Canada; Syracuse, NY; Montpelier and Burlington VT; and Montreal, Canada. Whew! There are many potential viewers for this one. The odds of cloudy weather are greatest from the Midwest through the northeastern U.S. and Canada. Even so, many of these cities will experience a totally awesome event. NASA and Espenak have maps of the path posted on the Internet as well for the really “Big Shew” coming in August 2045.
The August 12, 2045 event will be of slightly greater totality. It will carve a path from northern California east-southeastward through the Great Basin, Colorado and the Great Plains. It will cut a path from northwestern Arkansas through central and southeast Arkansas all the way down the spine of the Florida peninsula and southeastward into northern South America. The GE will be north of Cuba and totality will be approximately 6:05 minutes. Professor Guy is amending his living will to keep me on life-support through 2024, but I have little hope of being around for the 2045 eclipse. All of my loyal students under 60 years of age have a chance of seeing all three of these events with very little travel involved. It will be worth it! To view the NASA map for 2045, click Here.
Professor’s Note: Most spots on the Earth experience a total solar eclipse, on average, every 360 years. Some areas close to Hill ’n Holler Central will experience two in far fewer years. Little Rock will see the event in 2024 and 2045. Small areas of western Kentucky and southern Illinois will see one in 2017 and 2024. Statistics are nearly as fascinating as astronomy.
Much will be printed about these coming attractions in the next few months and years — including how to observe a partial solar eclipse safely. TIP: Don’t look at the Sun directly with the naked eye — Use an indirect projection method: Foster Grants just won’t hack it!
I wish to again acknowledge NASA and Fred Espenak’s contribution to this article from the NASA websites.
Remember, students, you heard it first from Professor Guy in the Hill ’n Holler Review — “strictly hush-hush and on the QT.”
©2013 Hill ’n Holler Review