330-PSA-114-60 (USN 1048561):  White dots in the center of sun spot are shown clearly for the first time in this photograph taken 80,000 feet above the Earth in Stratoscope I Balloon-Borne Telescope.  Less than 200 miles in diameter, these spots are apparently convection cells of rising gases, hotter than the surrounding area, but strongly suppressed by the magnetic field of the sun spot.  The long diameter of the umbra (black area) is roughly the diameter of the earth.   This photograph was taken by a Princeton University Team headed by Dr. Martin Schwarzechild on September 24, 1959, near Minneapols, Minnesota.  Stratoscope I was sponsored by the National Science Foundation of the Office of Naval Research.   Photograph released July 13, 1960.  (8/25/2015).
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