Letter from Thomas Gold to Dr D Martynov, President, Organizing Committee, Academy of Sciences of the USSR, Astronomical Council, Moscow, USSR Suggests that he should give a short survey at the October meeting of the most important data arising from the planetary radar work the Arecibo Ionospheric Observatory carries out. Suggests this because the work the Observatory carries out did not get on the October meeting programme because some of the staff from the Observatory could not get funds to attend the meeting. [31 July 1968]