The eruption of miniature filaments on the quiet Sun has been analyzed from time sequences of digital Hα filtergrams obtained at Big Bear Solar Observatory during 1997 September 18-24. The 2 days with the best image quality were selected for this initial study. During 13 hr of time-lapse observations on these 2 days, in an effective 640″ × 480″ area of quiet Sun close to the disk center, 88 erupting miniature filaments were identified. On average, these small-scale erupting filaments have a projected length of 19,000 km, an observed ejection speed of 13 km s-1, and a mean lifetime of 50 minutes from first appearance through eruption. The total mass and kinetic energy involved in a miniature filament eruption is estimated to be 1013 g and 1025 ergs, respectively. They are distinguished from macrospicules by the same criteria that large-scale filaments, before and during eruption, are distinguished from surges. Prior to eruption, one end, both ends, or the midsection of a miniature filament is superposed over a polarity reversal boundary on line-of-sight magnetograms. We conclude that miniature filaments are the small-scale analog to large-scale filaments.
All Science Journal Classification (ASJC) codes
- Astronomy and Astrophysics
- Space and Planetary Science
- Sun: filaments