Science

DSX

Van Allen Radiation Belt Research Satellite (Mission Ended 2021) · US Air Force Research Laboratory

For nearly two years, this satellite was the largest man-made structure ever built in space — bigger than the ISS, bigger than anything else in orbit — and almost nobody outside the Air Force had heard of it. DSX unfurled two 80-meter antenna booms specifically to fire very-low-frequency radio waves directly into the Van Allen radiation belts, testing whether Earth's own natural electron shield could be artificially cleared out to protect satellites flying through it. It outlived its planned one-year mission by nearly a year before being shut down in 2021, having proven a wave-injection technique no one had ever tried at this scale.