'Speed Bumps' From Auroras Can Slow Down Satellites

The rocket experiment to study the auroras lifted off from Norway in 2015. (Credit: NASA) Since the birth of the satellite age, scientists noticed that some spacecraft tend to slow down when the sun’s activity is highest, causing them to fall closer to Earth. If the spacecraft don’t carry enough fuel to boost them back to their intended orbits, they can eventually fall back down to Earth. Researchers quickly connected the slow-downs to the northern and southern lights, or auroras. These drifting patterns of colorful light are caused by charged solar particles striking Earth’s atmosphere at high speeds. Usually a visual feast, scientists have suspected for a while now that they can also loft pockets of air high enough for satellites to pass through. Used to skimming through the near-nothing of space, the satellites encounter drag within the air pockets, which slows them and pulls them closer to Earth. The ...