Helios (spacecraft)

Helios was a pair of NASA spacecraft launched in the 1970s to study the Sun's inner atmosphere and solar wind. Designed to operate close to the Sun, Helios provided detailed measurements of solar particles, magnetic fields, and radiation, helping scientists understand solar activity and its effects on Earth. The mission advanced knowledge of how the Sun's atmosphere behaves and influenced space weather forecasting. Helios's data contributed significantly to solar physics, and the spacecraft traveled within about 0.3 astronomical units (roughly 45 million kilometers) of the Sun, making it the closest any spacecraft has come to our star.