Saros Series 145 and the American Eclipse of 2017

Derryl Barr

Eclipse chasers have long known that whatever eclipse they have just observed, another will again occur with little variation 18 years and 11.32 days in the future. All they need to do is move approximately one third of the way around the world to the west and adjust their latitude by about 200 miles. The Saros series is the pulse of solar mechanics that has made eclipses predictable events even in ancient times. At any one time an average of 38 saros serirs are active, producing eclipses at their regular intervals. In this epoch saros series produce an average of 72 eclipses extending over a 1300 year period. Accordingly, some series are old, some middle aged and some young. Saros series 145 fits in the young classification of this remarkable rythmic order of nature, and on 2017 August 21 will produce only its eighth out a future total of 43 central eclipses. All but two of those being total. A variety of factors contribute to the determination to the type of eclipse a saros will predominately produce, and we are fortunate in that those factors for saros series 145 are most favorable for the production of total rather than annular events. While the series starts with eclipses of brief totality, celestial mechanics are slowly conspiring to bring about great things. By the 25th century celestical circumstances will produce 5 six minute plus and 3 seven minute plus eclipses in the series. While historically the first five totals preceding the series imminent return have had little impact on the history of astronomy, they each have etched unforgettable memories into the conscience of those who found themselves within its path. And while the future for 145 looks brighter than its past, each eclipse of each saros series has its own call to uniqueness.



Derryl Barr has been involved in astronomy for most of his whole life, and has recently witnessed for the second time Saturn's return to the exact location where he first telescopically observed it at the age of 13 in 1958, making him two in Saturnian years. He received his education from Westmar College, earning a Bachelor of Science degree in 1967, and the University of Northern Iowa where he earned his Masters in 1974. For an eighteen year period embracing the last decade of the 20th and first decade of the 21st century he wrote an astronomy column for the North Platte, Nebraska Telegraph, and between 2003 and 2011 taught an observational astronomy course at Mid-Plains Community College in North Platte. In 2004 he served as chairman for the first session of the 2nd International Solar Eclipse Conference held in Milton Keynes, England. He has observed 21 central eclipses as of this conference, having observed an eclipse from each of the seven continents. In addition he has observed from ingress to egress both of the transits of Venus. He plans to observe as many more eclipses as time will allot him. But doubts than any more Venusian transits are in his future. Currently he lives in Indianola, Iowa, occasionally substitute teaches, serves as a volunteer during Drake Observatory Lecture Nights, is a member of the Des Moines Astronomical Society, and spends as much time as he can with his three grandchildren.
Derryl Barr


Wednesday, August 16, 2017 - 14:45