Solar-geophysical data number 502, June 1986. Part 1: (Prompt reports). Data for May 1986, April 1986 and late data

Solar-Geophysical Data Number 502, June 1986; Part 1 (Prompt Reports); Data for May 1986, April 1986, and Late Data, contains the following; a detailed index for 1985 to 1986; data for May 1986--(IUWDS alert periods (Advance and worldwide), Solar flares, Solar radio emission, Standard mean solar magnetic field); data for April 1986--(Solar active regions, Sudden ionospheric disturbances, Solar radio spectral observations, Cosmic ray measurements by neutron monitor, Geomagnetic indices, Radio propagation indices); and late data-Cosmic ray measurements by neutron monitor, Geomagnetic indices, Calcium plague data.