Spatial evolution of magnetic fields as seen in coronal streamers to 12 R sub o during the solar cycle

Outer coronal photographs made from high altitude aircraft at the solar eclipses of 1966, '70, '72, '73, and '79 which sample various times in the solar cycle are presented. Coronal streamers extending from the solar limb to 12 R sub o are displayed. The evolution of the streamers as they distort magnetic field lines to large distances from the Sun is examined. Results show that the distortion is varied, that the polar plumes can be traced beyond 8 R sub o, diverging apparently along dipole field lines, and that the divergence varies along the solar cycle. Various changes in nonpolar streamers are discussed including the tendency to become radial beyond 3 to 5 R sub o as if controlled by the solar wind.