A six-hour sequence of observations of the sunspot BB 1680, NOAA 5612 obtained with the 65-cm vacuum reflector on August 2, 1989, is presented. The inflow of penumbral material to the umbra was found to be limited to the inner half of the penumbra. The outer half of the penumbra shows the Evershed effect outward flow extending beyond the penumbra.
High-resolution sunspot observations
1991-01-01
Sonstige
Keine Angabe
Englisch
High-resolution sunspot observations
Elsevier | 1991
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