Timelapse footage of the UArizona Bok 2.3-meter Telescope.

This timelapse footage of the UArizona Bok 2.3-meter Telescope at the Kitt Peak National Observatory (KPNO), a Program of NSF NOIRLab. As Earth rotates the stars appear to move across the dark night sky over the Tohono O'odham Nation Reservation where KPNO is located. The observing dome periodically rotates to allow the telescope to track its target object as it moves throughout the night. The UArizona Bok 2.3-meter Telescope was named after astronomer Bart Bok, a previous director of Steward Observatory, part of the University of Arizona. It is the largest telescope operated solely by Steward Observatory. In the background the larger Nicholas U. Mayall 4-meter Telescope is also busy observing.