During 1999 and 2000, we really expect some wild rides. We really don't know what effects we are going to see.
—JoAnn Joselyn, Cycle 23 Project, 1996
The instruments on board NASA's Solar and Heliospheric Observatory (SOHO) were routinely keeping watch on the Sun on April 7, 1997, when the Extreme Ultraviolet Imaging Telescope (EIT) camera picked up a typical garden-variety, class-C6 solar flare in progress. Scientists back on Earth watched while a shock wave from the flare passed through the local gases in the solar corona like the waves from a pebble dropped into a pond. It was a beautiful event to watch, looking for all the world like some artful animation rather than the awesome detonation that it actually was. In minutes, a ring of compressed gases had spread to engulf a patch of the Sun as big as the Earth. Radiation sensors onboard the geosynchronous GOES weather satellites detected a rain of flare particles minutes later; meanwhile, radio telescopes began to detect the telltale radio waves from a Type II burst on the Sun. The CME, in its haste to leave the Sun, had shocked and compressed solar plasma ahead of it, snowplowing them into walls of stripped atoms and magnetic fields that emitted powerful blasts of radio waves. At 10:00 A.M. EDT, as the shock wave spent itself, the LASCO instrument witnessed a major CME grow to the size of the Sun and larger.
Three days later, on April 10, 7:00 P.M. EDT, the WIND and SOHO satellites, parked one million miles from the Earth toward the Sun,