At the latitude of the Grafenegg in Lower Austria, the Earth’s surface is spinning through space at 1,108 Km/h – racing towards the eastern horizon in order in complete one rotation every 24 hours.
Earth-Spin no.1: Grafenegg is a simple annotation of the planet Earth. Cut into the earth itself in two-meter high, 50 cm deep letters, stretching roughly 17m across the closely cropped lawns of the Grafenegg grounds, the intervention spells out this speed and marks the direction of spin with a long arrow (also cut into the grass). Through this simple action, the viewer’s perspective is altered – reminded that the seemingly still and stable grounds of an Austrian castle are actually moving at great speed through the blackness of space.
Calculating the speed of the Earth’s Surface:
The latitude of Grafenegg = 48º25’47.79″
or in decimal: 48.42972222222222
At the equator, the circumference of the Earth is 40,070 Km
The day is 24 hours long.
Therefor the speed of the surface at the equator is 1670 kilometers/hour. This speed decreases by the cosine of your latitude, so that:
At a latitude of 45 degrees,
cos(45) = .707
The speed therefor is .707 x 1670 = 1180 kilometers/hr.*
Therefor at the latitude of Grafenegg:
Latitude of 48.42972222222222
cos(48.42972222222222) = 0.663538202600502
0.663538202600502 x 1670 = 1108.10879834283767 Km/h
Therefor the speed of Earth’s Surface at Grafennegg =
1108 Km/h