[en] We present the first observations of the initiation of a coronal mass ejection (CME) seen on the disk of the Sun. Observations with the EIT experiment on SOHO show that the CME began in a small volume and was initially associated with slow motions of prominence material and a small brightening at one end of the prominence. Shortly afterward, the prominence was accelerated to about 100 km s[SUP]-1[/SUP] and was preceded by a bright loop-like structure, which surrounded an emission void, that traveled out into the corona at a velocity of 200 400 km s[SUP]-1[/SUP]. These three components, the prominence, the dark void, and the bright loops are typical of CMEs when seen at distance in the corona and here are shown to be present at the earliest stages of the CME. The event was later observed to traverse the LASCO coronagraphs fields of view from 1.1 to 30 Ro. Of particular interest is the fact that this large-scale event, spanning as much as 70 deg in latitude, originated in a volume with dimensions of roughly 35" (2.5 x 10[SUP]4[/SUP] km). Further, a disturbance that propagated across the disk and a chain of activity near the limb may also be associated with this event as well as a considerable degree of activity near the west limb.
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Dere, K. P.; Naval Research Laboratory Washington D.C., E.O. Hulburt Center for Space Research
Brueckner, G. E.; Naval Research Laboratory Washington D.C., E.O. Hulburt Center for Space Research
Howard, Russell A.; Naval Research Laboratory Washington D.C., E.O. Hulburt Center for Space Research
Koomen, M. J.; Naval Research Laboratory Washington D.C., E.O. Hulburt Center for Space Research ; , Sachs Freeman Assoc
Korendyke, Clarence M.; Naval Research Laboratory Washington D.C., E.O. Hulburt Center for Space Research
Kreplin, R. W.; Naval Research Laboratory Washington D.C., E.O. Hulburt Center for Space Research ; , Universities Space Research Assoc
Michels, D. J.; Naval Research Laboratory Washington D.C., E.O. Hulburt Center for Space Research
Moses, J. D.; Naval Research Laboratory Washington D.C., E.O. Hulburt Center for Space Research
Moulton, N. E.; Naval Research Laboratory Washington D.C., E.O. Hulburt Center for Space Research ; , Allied Signal Corp
Socker, Dennis G.; Naval Research Laboratory Washington D.C., E.O. Hulburt Center for Space Research
St. Cyr, O. C.; Naval Research Laboratory Washington D.C., E.O. Hulburt Center for Space Research ; , Computational Physics Inc
Delaboudinière, J. P.; Institut d'Astrophysique Spatial, Université
Artzner, G. E.; Institut d'Astrophysique Spatial, Université
Song, X. Y.; Institut d'Optique Théorique et Appliquée
Chauvineau, J. P.; Institut d'Optique Théorique et Appliquée
Marioge, J. P.
Defise, Jean-Marc ; Université de Liège - ULiège > CSL (Centre Spatial de Liège) - Instrumentation et expérimentation spatiales
Jamar, Claude ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Département d'astrophys., géophysique et océanographie (AGO)
Rochus, Pierre ; Université de Liège - ULiège > CSL (Centre Spatial de Liège) - Instrumentation et expérimentation spatiales
Catura, R. C.; Nasa Goddard Space Flight Center
Lemen, J. R.; Nasa Goddard Space Flight Center
Gurman, J. B.; Observatoire Royal de Belgique
Neupert, W.; Observatoire Royal de Belgique
Clette, Fr.; Laboratoire d'Astronomie Spatiale
Cugnon, P.; Laboratoire d'Astronomie Spatiale
van Dessel, E. L.; Max-Planck-Institut für Aeronomie
Lamy, Philippe L.; Space Research Group, School of Physics and Space Research, University of Birmingham
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