2012 05 17 – NOAAs 11476, 11477, 11478, 11479, 11482, 11484, NE Prominence

1245 UT – 1845 UT
Temp: 20-30C, calm – S 5mph, clear.
Seeing: Wilson 4.8-1.2, Transparency: 5/6-4/6, 50x.
Maxscope DS 60mm H-alpha, LXD75, Baader Planetarium Hyperion 8-24mm Mark III.

During the time I observed, a very large prominence off the northeast limb was enlarging and in the process of ejecting as it broke free from the magnetic fields supporting it. I’ve never visually witnessed that large of a prominence breaking away from the Sun before. What really stunned me was how bright it remained over several hours that far off the limb. I grabbed an 8-sketch sequence spanning over 6 hours of the event, not including the full disk rendering I recorded earlier in the day. The last 35 minutes of my session, the prominence became very faint and diffuse. I stopped seeing any connection from the limb after 1717 UT. Of course, that doesn’t necessarily mean there wasn’t, but was perhaps too faint for my tired eyes to see. Please click in the gallery at the bottom of this post to view the entire sequence individually.

Sketches created at the eyepiece with black Strathmore Artagain paper, white Conte’ crayon and pencil, white Prang color pencil, Derwent charcoal pencil, black oil pencil.

There was an coronal mass ejection (CME) recorded between the hours 0137 UT – 0648 UT by SOHO that began with an M5 class flare and reached S2 at its peak, hurling solar protons into space at speeds faster than 1500 km/s (per Spaceweather.com) 1476, in all its glory, has finally reached the western limb and is about to disappear from our view. It went out with a bang. Very condensed, short and slender prominences were in that area and the plage was very bright.