Tilting and Vibration of the Skylab Building at the South Pole.

The angular stability of a large building at the South Pole was measured using a tiltmeter for a period of 11 days. Both the top and bottom floors wobble by approximately 20 seconds of arc on a diurnal cycle, and show long-term drifts of up to 60 seconds of arc. The top floor also showed vibrations of up to 30 seconds of arc that were excited by people moving about in the building. These vibrations were not present in the ground floor. This building is not a suitable mounting platform for telescopes with stringent pointing requirements; its foundation does not vibrate, however, and indicates that such a platform could be built.