First Results on Visualization and Verification of the STEREO Heliospheric Imager CME Catalogue with In Situ Data from the Heliophysics System Observatory

Abstract:

The space weather community has recently seen major advances in the prediction of the speed and arrival time of solar coronal mass ejections at Earth and other planets. Since the start of the STEREO mission in 2006, each of the heliospheric imagers (HIs) onboard the Ahead and Behind spacecraft has successfully tracked hundreds of CMEs. The advantage of HI is that CMEs can be followed for a significant part of the inner heliosphere, and the CME evolution in direction and speed is better constrained than by coronagraphs alone. By tracking and cataloguing each of those CMEs in the EU HELCATS project, we can apply geometrical modeling (FPF, HMF, SSEF) techniques on single-spacecraft HI observations to extract the expected planetary impacts of each CME. These arrivals are then verified or refuted by in situ solar wind plasma and magnetic field observations provided by the spacecraft forming the Heliophysics System Observatory (HSO), such as Wind, ACE, Venus Express, MESSENGER, and STEREO-A/B, for which various ICME catalogues are gathered and updated in the course of HELCATS.
A first assessment on the relationship between CME HI and in situ observations is discussed, such as occurrence rates, speeds and arrival times and magnetic field strength. We also present visualizations of the HI CME catalogue and the corresponding in situ observations. The presented work has received funding from the European Union Seventh Framework Programme (FP7/ 2007-2013) under grant agreement No. 606692 [HELCATS].