The Halloween solar storms of 2003 were a wake up call for the risks that solar flares and coronal mass ejections pose to our increasingly technological society.
It had been three and a half years since the sun last erupted in fury…at the peak of an 11-year cycle of solar flare-ups.
Back then, we got ready for it… by shutting down satellites that were vulnerable to high levels of radiation. But no one expected this. In what should have been a low point in solar activity, the sun erupted in a series of massive explosions, called coronal mass ejections, or CMEs.
Electrified gas clouds weighing billions of tons raced outward. Solar telescopes recorded the action… The largest emission of solar x-rays ever seen. The hottest flares, at tens of millions of degrees. And the fastest… reaching speeds clocked at six million miles per hour.
The sun became a giant plasma weapon… more potent than any in science fiction… and pointed right at our home planet. On Earth… the Halloween storms produced some of the most spectacular auroras ever seen at the north and south poles. They also brought jolts of electricity that caused power outages in Sweden, and disrupted airline navigation.
In space, these storms damaged 28 communications satellites, and destroyed two. And they didn’t stop there. As the energetic surge swept past Mars, it was so strong it burned out the radiation monitor aboard the spacecraft, Mars Global Surveyor. Ironically, this instrument was designed to study radiation that human explorers might encounter on future missions beyond Earth.
Months later, the rush of solar energy washed over the two Voyager spacecraft, on their way to the far reaches of the solar system. CMEs like these have been known to blast their way out the far edges of the solar system, where the solar wind meets the flow of gas around the galaxy itself.
