The NASA Astronomy Picture of the Day entry dated August 28, 2026 presents a star-trail image made at the latitude of ESO's Paranal Observatory in Chile, roughly 25 degrees south. According to the accompanying explanation, Earth's rotation carries the surface eastward at over 1,500 kilometers per hour there — faster than the speed of sound at sea level, though the motion itself goes unfelt.
The image was assembled from a digital stack of 300 consecutive 25-second exposures taken with a camera fixed to a tripod. The resulting concentric arcs are centered on the south celestial pole, the southern extension of Earth's axis of rotation. Beneath that point appears AT 3, one of the observatory's operating 1.8-meter auxiliary telescopes, faintly lit in the foreground.
The entry credits the image to Osvaldo Castillo, with text by Jerry Bonnell, Cecilia Chirenti, Robert Nemiroff and Keighley Rockcliffe. The page also notes that APOD's main site is moving from apod.nasa.gov to science.nasa.gov/apod.




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