September 10, 2010, 12:00 pm - 1:00 pm

September 10, 2010, 12:00 pm - 1:00 pm

Propagation of an Earth-directed coronal mass ejection in three dimensions

Shane Maloney (Trinity College Dublin)

Stereoscopic imaging of solar coronal mass ejections (CMEs) has provided in- sight into their three-dimensional (3D) propagation in the Heliosphere. However, the mechanisms governing CME evolution remain unclear due to difficulties in reconstructing their true 3D structure. Here we use a new reconstruction technique to resolve a full CME front in 3D, enabling us to quantify its deflection from high solar latitude into the ecliptic, and measure its increasing angular width and propagation from 2–46 solar radii. We conclude that the CME moves along the drawn-out magnetic field of the solar dipole and suggest that its increasing width is due to an overpressure of the CME relative to the surrounding corona. Beyond heights of approximately 7 solar radii, we show that its motion is determined by aerodynamic drag in the solar wind and using our reconstruction as input for a 3D MHD simulation we determine an accurate arrival time at the L1 point near Earth.