Automation of Area Measurement of Sunspots

Digital Image Restoration

Pattern Recognition · 1979 · 646 citations

On the umbra-penumbra area ratio of sunspots

Peter Brandt, W. Schmidt, M. Steinegger · Solar Physics · 1990 · 63 citations

Natural Sciences, Geography, Physical Geography +6

On the Energy Balance of Solar Active Regions

M. Steinegger, Manuel Vázquez, José Antonio Bonet et al. · The Astrophysical Journal · 1996 · 55 citations

Natural Sciences, Astronomy, Earth Sciences +17

A study of the contrast of sunspots from photometric images

J. G. Beck, G. A. Chapman · Solar Physics · 1993 · 40 citations

Natural Sciences, Astronomy, Physics +12

Photometric measurements of solar irradiance variations due to sunspots

G. A. Chapman, A. D. Herzog, D. E. Laico et al. · The Astrophysical Journal · 1989 · 17 citations

Natural Sciences, Astronomy, Physics +17