AR11429 was the first big reversed spot group for cycle SC24. It was also an "Island Delta" class, at least briefly. Would it return after passing the solar far-side? Yes - but only just. The image shows two tiny spots at the site March 31. They soon vanished - but the filament at the site took on a life of its own - becoming the most conspicuous feature on the sun in H-alpha. Zirin (Astrophysics of the Sun) warns us of the potential for major SPOT-LESS flares at such a site.
A small ejection of part of the filament was logged on April 3 (Fig, rhs). The wide tuning range of the Lumicon showed the Doppler-shifted ejecta was approaching at maybe 200km/sec. Many more partial ejections followed for a week- and it logged a GOES C3.9 flare on April 9 - before going behind the west limb. Will the filament survive to return at the end of the month?