Helios mission support

With Helios-1 completing its third perihelion and Helios-2 passing its first perihelion, much valuable scientific data were obtained about the inter-earth-sun regions. The first solar occultation of Helios-2 is anxiously awaited as the next important mission phase. Preparations are underway for Helios-2 first entry into solar occultation in mid-May 1976. This article reports on the activities around Helios-1 and -2 perihelions.