Morphology and Evolution of a Polar Coronal Mass Ejection

I. CABELLO; H. CREMADES; L. BALMACEDA; I. DOHMEN

San Francisco

Congreso; AGU Fall Meeting; 2015

American Geophysical Union

Flux-rope coronal mass ejections (CMEs) are believed to be organized along a main axis of symmetry, therefore they exhibit different  appearances depending on the axis orientation with respect to the observer. There are observational reports of CMEs seen along their main axis (axial perspective) and perpendicular to it (lateral perspective), however to date no simultaneous observations of both perspectives from the same CME have been reported. The stereoscopic views of the telescopes aboard the Solar-Terrestrial Relations Observatory (STEREO) twin spacecraft, in combination with the views from the Solar and Heliospheric Observatory (SOHO) and the Solar Dynamics Observatory (SDO), allow us to study for the first time simultaneously the lateral and axial perspectives of the three-dimensional configuration of a polar coronal mass ejection. In addition to the validation of the observationof both perspectives, this study shows that the flux rope's angular  diameter D and the extent L of the associated prominence, grow up linearly with time until the outer edge of the coronagraph?s field of view. The angular width of the outer envelope in the axial (AW_D) and the lateral (AW_L) perspectives present only this behaviour from the low corona to ≈ 5Rsun. The ratios L/D and AW_L/AW_D yield 1.6, the same value obtained previously from averaging different events exhibiting only one of the perspectives.