Tuesday, 19 March 2013

Graceful eruption

This quiescent prominence lifted off the sun's SW limb on February 20th (UT) .There was plenty of time to sketch it since the ejection velocity was a low 25km/sec : fairly typical for a quiet region filament (QRF). Active region filaments (ARF) under special circumstances can eject at over 3000km/sec - an incredible velocity even given the very low density of the material involved. This filament was formed by plumes or 'streaks' of low-power magnetic fields, the relics of decayed sunspot groups.
   While the sun is abnormally quiet at present, from time to time it still hosts a range of interesting and beautiful transients.