The Wilkesboro Quilt Block Sundial

The Wilkesboro Quilt Block Sundial. . , Reading the Sundial , Look at the shadow cast by the rod, (called gnomon; pronounced "no-mon"), and and notice where the center of the shadow falls on or between the numerals. Use the outer largest numerals when Daylight Savings time is in effect use the inner numerals for the rest of the year. Hours and half hours are marked by the radial lines on the quilt pattern., Finding Clock Time , Clock time can be found by using the Equation of Time graph. The difference between solar time and clock time varies according to a repeating yearly cycle known as the Equation of Time. For instance, on December 15 the graph indicates -5, so subtract 5 minutes from your Sundial reading to get Clock time. In this case, the Sundial could indicate 12:00, which is 11:55 Clock time., The Equation of Time , [The graph as described in the previous paragraph], Understanding Solar Time , Solar Time is defined by the Sun's apparent motion from noon of one day until noon of the next day. The precise reference is local solar noon or high noon, when the Sun is at its highest point in the sky, exactly halfway between sunrise and sunset. At this moment, the shadow cast by the gnomon is exactly vertical on the dial face. This is indicated on the Sundial by the small sun near the bottom center of the dial face, Notice this occurs at 12:25 pm by the inner numerals., Before the introduction of time zones and Daylight Savings time most Sundials indicated Local Apparent time (LAT). The inner numerals indicate zonal solar time, to be used when Standard time is in effect. This is LAT that has been advanced by 25 minutes to compensate for Wilkesboro's location in the western part of our time zone, Understanding Solar Time (cont.) , The Wilkesboro Quilt Block Sundial is set to show the solar time at the central meridian of the Eastern Time Zone, the same as we do with our clocks, in contrast to LAT, which varies by location, all zonal solar time. Sundials in our time zone should show the same time at the same instant., The outer numerals are zonal solar time set forward by one hour, to be used during Daylight Savings time.Zonal solar time. is corrected using the Equation of Time, as explained at left and the result is a mean solar time at the central meridian of the time zone, which is the basis for civil clock time., The Vertical Sundial , The face of the sundial represents a mathematical projection of the Sun's daily path across the sky. The gnomon is the steel metal rod in the center of the dial face and is aligned to be parallel to the Earth's rotational axis. The upward tilt is equal to the latitude at the Sundial and the top end of the gnomon points toward the north celestial pole, very close to Polaris , the North Star., The Quilt Block , The Wilkesboro Quilt Block is an original pattern quilted by Joann Scorof of North Wilkesboro. The pattern depicts the fields and streams along the Yadkin Greenway with the Blue Ridge mountains in the background and Carolina blue skies, with billowing clouds., "The Sundial Quilt Block serves two purposes , first and foremost, displaying the heritage craft of quilting: similar to the barn quilts installed by the Wilkes County Quilters, Inc. and the Cultural Arts Council of Wilkes. Secondly, it serves as a beautiful backdrop for the Sundial and represents Wilkesboro. and our county," states Ms. Scorof., Project Sponsors and Contributors , Astronomer Bob Hampton , Best Image Signs and Graphics , Cultural Arts Council of Wilkes , Duke Energy Foundation , Façade Grant from the Town of Wilkesboro , Grassroots Arts Program Grant of the NC Arts Program , Quilter-Joann Scorof , Welders-Junior Shelton and Arvil Royal , Wilkes Tourism Development Authority