Solar Dynamics Observatory/NASA
Just when the sun was looking especially lethargic, a violent eruption left behind a vast chasm of superheated gas on the solar surface. On September 29–30, a searing filament of charged particles blasted away from the sun at more than 3 million kilometers per hour. The event left behind a scar that marks where the filament escaped into space. NASA’s Solar Dynamics Observatory captured this image by combining two different wavelength views. Yellow highlights plasma moving along the sun’s magnetic fields, and red-orange helps highlight the sun’s plasma at 50,000° Celsius.
The prominent pockmark caught astronomers’ attention because, for the most part, the sun has been unexpectedly quiet in the peak year of its 11-year solar cycle. In fact, the sun is on track to have its quietest peak year since the early 1900s (SN: 11/2/13, p. 22). Still, what NASA has dubbed the Canyon of Fire is a sobering reminder that the sun is a tempestuous and unpredictable place.