Thrale Field Observatory
Public dark-sky observatory
Loading Thrale Field Observatory
The world
One night's observing log — sheet 4,118, opened at civil dusk, signed off at nautical dawn.
The mechanic
The page turns on the wall clock at the true sidereal rate, not on the scrollbar. Scroll only reveals. Derived from the physical fact that celestial motion does not depend on the observer.
The control case. Degrades to a 517-mark vector plate of the same catalogue with JS off, and under reduced motion.