Helios 2A is a satellite launched by NASA on December 21, 1976, as part of the Helios program. It was designed to study solar phenomena and gather data about the sun's influence on the solar system. The satellite operated in a highly elliptical orbit, allowing it to get close to the sun and collect valuable information. The primary mission of Helios 2A was to measure solar wind, magnetic fields, and cosmic rays. It provided crucial insights into solar activity and its effects on space weather, contributing to our understanding of the sun's behavior and its impact on Earth and other planets.