Perryville in Perry County, Missouri — The American Midwest (Upper Plains)
Great American Eclipse of 2017
Perry County Missouri
(panel 1 – Eclipse)
This sundial commemorates the total solar eclipse that occurred here on August 21, 2017, starting with a partial eclipse at 10:51:05 solar time (11:53:43 AM CDT), reaching a peak of totality at 12:20:04 solar time (1:22:41 PM CDT), and ending with a partial eclipse at 13:46:23 solar time (2:49:01 PM CDT).
Shadow-paths traced by the tip of the triangular-shaped gnomon follow four datelines on the sundial. On December 21 each year, the shadow of the tip follows along the line labeled Southern Solstice (or winter solstice). On March 21 and September 23, it follows the Equinox line. On June 21, the shadow of the tip follows the Northern Solstice (or summer solstice) line. Each year, the shadow-path of the tip brings to our memory the total eclipse by moving along the Eclipse line on August 21. As the tip traverses the Eclipse dateline, it encounters markers at the times of the onset, the peak of totality, and the end of the eclipse event that occurred here.
(panel 2 – Time)
This sundial shows solar time. The hour marked 12 indicates solar noon — the time when the sun at this location reaches its highest elevation of the day, 1 indicates one hour after solar noon, etc. To get
Three factors relate the time indicated by this sundial to civil time - the time indicated by your watch or cellphone. This relationship is
t CIVIL = t SUNDIAL +D – L – EOT
D = +1 hour when "daylight savings time" is in effect and 0 when not. L accounts for the difference between the longitude 89.86°W of the dial's location and the longitude 90°W used for Central Standard Time; this difference of 0.14° implies that L is 40 seconds. EOT stands for "Equation of Time." This accounts for the earth's noncircular, tilted orbit around the sun. EOT depends where the earth is in its orbit around the sun, that is, on the date, as seen here graphically.
(panel 3 – Sundial)
Design. Donald L Snyder of St. Louis, a Member of the North American Sundial Society and the St. Louis Astronomical Society, designed the sundial. It commemorates the occurrence in Perry County, Missouri, of the Great American Eclipse that occurred
Sundial. Abraham Mohler, St. Louis sculptor and artist, made the dial plate.
Gnomon. William Turner, of Turner Associates in St. Louis, made the gnomon.
Pedestal. Earth Works Inc. made the pedestal of limestone they quarried in Perry County.
Location. This sundial is located at the Perry County Courthouse in Perryville, Missouri. Extensive renovation of the Courthouse was completed in time for its celebration with this sundial on August 19, 2017, the weekend of the total solar eclipse.
Erected 2017 by Perry County Missouri.
Location. 37° 43.512′ N, 89° 51.794′ W. Marker is in Perryville, Missouri, in Perry County. Marker is at the intersection of North Jackson Street and West St. Joseph Street, on the right when traveling north on North Jackson Street. Touch for map. Marker and sundial monument are located on the Perry County Courthouse grounds, near the southwest corner of the courthouse. Marker is at or near this postal address: 15 West Sainte Marie Street, Perryville MO 63775, United States of America.
Other nearby markers. At least 2 other markers Lewis and Clark in Illinois (approx. 12½ miles away in Illinois); Popeye (approx. 12½ miles away in Illinois).
More about this marker. Marker consists of three metal plaques mounted on three sides of a waist-high, polished local limestone pedestal. There is a commemorative sundial mounted on top of the pedestal.
Also see . . .
1. Eclipse History. Many Scientific Discoveries have been made during solar eclipses. The moon’s unique ability to cover the sun’s disk has allowed investigations of the corona and chromosphere as well as verification of the theory of General Relativity. (Submitted on July 5, 2018, by Cosmos Mariner of Cape Canaveral, Florida.)
2. 9 Facts About the US Total Solar Eclipse of August 21, 2017. The total solar eclipse of August 21, 2017 was visible from a narrow path spanning the US from the West Coast to the East Coast. Here are all the facts you need to know about this once-in-a-lifetime event. (Submitted on July 5, 2018, by Cosmos Mariner of Cape Canaveral, Florida.)
3. Wikipedia Entry. A large number of photographs of the eclipse are on this page, under Gallery. (Submitted on August 18, 2018, by J. J. Prats of Powell, Ohio.)
Additional keywords. astronomy
Categories. • Air & Space • Man-Made Features •
Credits. This page was last revised on August 23, 2018. This page originally submitted on July 4, 2018, by Cosmos Mariner of Cape Canaveral, Florida. This page has been viewed 124 times since then and 3 times this year. This page was the Marker of the Week August 19, 2018. Photos: 1, 2, 3, 4, 5, 6. submitted on July 4, 2018, by Cosmos Mariner of Cape Canaveral, Florida. 7, 8. submitted on August 18, 2018, by J. J. Prats of Powell, Ohio. • Bill Pfingsten was the editor who published this page.