English: The Bracewell Radio Sundial at the Very Large Array in New Mexico. Named for Ron Bracewell, this sundial marks on the ground positions of the shadow of the central sphere (the gnomon) at different times of day and times of year. The shadow on Dec 22, 2017, falls on the winter solstice line, at the 1:00 PM (solar time) mark in this photo. The other two lines of spots north of the gnomon are for the equinoxes and the summer solstice. More closer lines of spots south of the gnomon mark positions of shadows of radio sources in Cygnus A and Cassiopeia A.
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