DMSP Satellite Observes Aurora
October 25, 2002
As seen on the above DMSP satellite photo, nearly all of eastern North America was clear on the night of October 2. The day before, a solar wind stream buffeted Earth's magnetic field, triggering a strong geomagnetic storm. Auroras typically form well below the altitude of the DMSP satellites, which orbit 450 miles (720 km) above the Earth. During the display on October 2, sky watchers in Canada and the US were able to see colorful northern lights that were visible from the Arctic Ocean to Arizona! On the above photo, since the Moon was in the waning crescent phase, nighttime lights from cities as well as the norhtern lights are easily visible. If you hope to catch a glimpse of an aurora, it might be worthwhile to keep your eyes peeled on those moonless nights when clear skies prevail.