Analysis of magnetic field data from Pioneer Venus orbiter

The subject grant (NAG 2-501) supported the analysis of magnetic field data from the Pioneer Venus orbiter for the period 10/1/87 to 9/30/94. During that period, 188 papers were contributed to scientific meetings that either analyzed the magnetometer data or used the data as part of the analysis of a scientific problem. Further, 107 papers were published in research journals and books. The magnetic moment of Venus was described. Venus was found to be essentially devoid of any intrinsic magnetic field. There was evidence though for the presence of lightning in the Venus atmosphere. The altitude distribution of impulsive signals in the night atmosphere was mapped and geographic clusters were found, most probably associated with local time ordering. A new means to create flux ropes in the ionosphere was postulated. On the nightside, ionospheric holes, ionospheric clouds, and tail rays were studied. The subsolar ionopause and the magnetic barrier were examined as was the altitude asymmetry of the ionopause, properties of the magnetosheath, and location of the bow shock upstream waves.