Friday, 18 October 2013

Brief Glory!

A giant of its kind, this huge prominence was glimpsed through heavy cloud. Over 100Mm high it was clearly erupting off the disc - and did so some hours later - resulting in a small CME that was not 'geoeffective'. The logs from 14 days earlier showed a hedgerow at the western limb with the same coordinates as shown above. The eruption caused the two foreground filament to vanish also.

Friday, 4 October 2013

Big Filament Ejects

Five NSO GONG images (c) show September's big filament as it crosses the sun - for the second time!
These five GONG views show the filament tilted from our line-of-sight in views 1, 3, 4 and 5. Note how different it looks as the l-o-s changes: showing complex details of the footpoints.View 2 shows it crossing the central meridian: we see it from directly overhead. Fig 5 shows it at the moment of lift off. It ejected at 900km/s, causing widespread aurorae on planet Earth. Heliocentric positions show it had made almost 2 complete rotations of the Sun at the time of liftoff! A very long-lived filament. In the process, H-alpha users saw some great prominences. Will the filament reform at the site?