International Solar-Terrestrial Physics Program

The International Solar-Terrestrial Physics (ISTP) Program was a cooperative effort involving NASA, the European Space Agency (ESA), and Japan's Institute of Space and Astronautical Science. Launched in the 1980s, its primary goal was to investigate the connection between the Sun and Earth. This program utilized a series of spacecraft, including NASA's Wind and Polar, ESA's Solar and Heliospheric Observatory (SOHO) and Cluster missions, and Japan's Geotail satellite. These missions aimed to gather comprehensive data on solar activity and its effects on Earth's magnetosphere and space environment, contributing to the understanding of phenomena like space weather.12