Eric wrote:
I have found alot of confusion from amateurs about prominences, flares, and CME's.
Definitely, particularly with respect to the difference between a flare and a coronal mass ejection (CME). But IMHO it's caused more by a lack of republication of accepted classification schemes. For most amateurs they are hard to find online or in print. For prominences, Zirin's _Astrophysics of the Sun_ (1988, Marriot Lib. Call No. QB521 .Z57 1988) is the source I've usually seen quoted. Noted amateur David Knisely has done a good summary of definitional terms from Zirin ( http://www.prairieastronomyclub.org/halpha.htm ) - that in plain language are pretty hard to interpert or apply without the example photos in Zirin's book. In Zirin's definitions, a prominence is a supertype definition covering any "H-Alpha emission features projecting beyond the limb of the sun," and covers a pretty broad range of phenomena from the small inverted Y shape seen last Saturday, up to an including the large 20 latitude degree spanning coronal loops in the Devil Sun picture ( http://antwrp.gsfc.nasa.gov/apod/ap030418.html ) or the eruptive prominence shown in the very cool April 3, 2000 APOD ( http://antwrp.gsfc.nasa.gov/apod/ap000403.html ) that you pointed to. Types of prominences are not restricted to just large coronal loops or large eruptive prominences. Knisley's quote summary of Zirin goes on to say that: "They generally come in two broad classes: Active (limb flares, surges, sprays, loops), and Quiescent (Quiet Region Filaments, Active Region Filaments)." CLASS 1: QUIESCENT FILAMENTS/PROMINENCES (long lived, fairly static) a. QRF (Quiet Region Filament) ie: hedgerow, curtains, floating arches, arcs, fans, etc. b. ASCENDING PROMINENCES (end of the quiescent phase) "Disparition Brusque" ("lifting off") eruption. c. ARF (Active Region Filament): a filament in or near an active region (netural line filaments). CLASS 2: ACTIVE FILAMENTS/PROMINENCES (short-lived, moving) a. LIMB FLARES (bright blobs, sometimes expanding into eruptive prominences). b. SURGES: collimated ejected material previously not seen (very sudden jet of gas). c. SPRAYS: uncollimated ejecta previously visible as pre-flare elevated features (violent explosion). d. FLARE LOOPS and CORONAL RAIN (often post-flare ejecta or other gas). See Knisely's online summary for a more detailed description of these classes. (I haven't seen any online images illustrating the Mt. Wilson sunspot classification scheme.) The plain text defintions don't give much clear guidance for the average amateur to apply. I've always found Maurice Gavin's drawings summarizing Zirin's definitions to be helpful when trying to describe prominences in plain text: http://home.freeuk.com/m.gavin/promtypex.gif The AAVSO Solar Division has a good gallery containing images of many of these prominence classes (although they aren't labeled with the Zirin definitions): http://www.aavso.org/observing/programs/solar/limb.shtml http://www.aavso.org/observing/programs/solar/limb1.shtml http://www.aavso.org/observing/programs/solar/solarphoto.shtml Best wishes - Kurt P.S. - Maybe a good solar imaging project for you lurking Sun party regulars would be to take an image of one of each of the Zirin prominence types. For lurkers, the AAVSO also has a good online summary of the Zurich classification system for describing sunspots. http://www.aavso.org/observing/programs/solar/zurichindex.shtml _______________________________________________ Sent via CSolutions - http://www.csolutions.net