Local Time

The painted steel gnomon is mounted on an existing solar panel utility pole at the Environmental Learning Center.

The gnomon's shadow crosses the dark brown line at noon Pacific Standard Time and the light brown line at noon Local Apparent Time, when the sun is due south. The layout of the lines is entirely site-specific. The separation between the lines shows the difference between solar time and clock time.

The center of the shadow of the elliptical portion of the gnomon is used for determining noon. The shadow of the ellipse at noon is more or less circular depending on the time of year.

The stones show where the shadow crosses the lines on the first day of each month, tying the clock into the calendar and the movement of the Earth around the sun.

installation step 1: locating the centerline of the gnomon on the pole

installation step 2: bolting the mounting bracket onto the pole

installation step 3: hanging the gnomon from the bracket

installation step 4: pivoting the gnomon into position

installation step 5: pivoting the gnomon into position

installation step 6: seating the gnomon in the bracket

installation step 7: bolting the gnomon to the bracket

installation step 8: laying out the lines on the ground, using string and a giant protractor to mark where the shadow falls on different dates based on the sun's elevation angle

installation step 9: determining the separation between the lines, using another protractor to measure azimuth angles

installation step 10: construction of the lines using weed control fabric and landscaping bark

Description

painted steel, bark, stones
temporary installation, 7-2011 through 11-2011

A reminder of time measured by the sun, and of how a more natural experience of time depends on our location – where we are on Earth, and where the Earth is in space.

The sculpture on the pole is the gnomon of a sundial. When the center of its shadow crosses the straight line on the ground, the sun is due south and the time is local apparent noon, or mid-day as it was understood before the invention of mechanical clocks and time zones. When the center of the shadow crosses the curved line, the time is noon Pacific Standard Time and 1:00 Daylight Savings Time.

Part of the Heaven and Earth exhibit at Carkeek Park in Seattle.

For

Center on Contemporary Art, Seattle Parks and Recreation

Type

public art, outdoor, sundial

URL

heavenandearth.carkeekpark.org/babcock3.htm