# Multi-spacecraft Observations of the Coronal and Interplanetary Evolution of a Solar Eruption Associated with Two Active Regions

## TL;DR

This study tracks the evolution of a solar eruption from the Sun to interplanetary space using multi-spacecraft observations, revealing how magnetic interactions influence CME trajectory, shape, and arrival times at different locations.

## Contribution

It provides a comprehensive analysis of a CME linked to two active regions, combining remote sensing and in situ data with modeling to understand its complex propagation.

## Key findings

- CME was deflected eastward and southward by magnetic pressure from active regions.
- CME's arrival time at VEX was not earlier despite proximity to the Sun, highlighting shape and direction importance.
- ICME was compressed radially but extended transversely in interplanetary space.

## Abstract

We investigate the coronal and interplanetary evolution of a coronal mass ejection (CME) launched on 2010 September 4 from a source region linking two active regions (ARs) 11101 and 11103, using extreme ultraviolet imaging, magnetogram, white-light and in situ observations from SDO, STEREO, SOHO, VEX and Wind. A potential-field source-surface model is employed to examine the configuration of the coronal magnetic field surrounding the source region. The graduated cylindrical shell model and a triangulation method are applied to determine the kinematics of the CME in the corona and interplanetary space. From the remote sensing and in situ observations we obtain some key results: (1) the CME was deflected in both the eastward and southward directions in the low corona by the magnetic pressure from the two ARs and possibly interacted with another ejection, which caused that the CME arrived at VEX that was longitudinally distant from the source region; (2) although VEX was closer to the Sun, the observed and derived CME arrival times at VEX are not earlier than those at Wind, which suggests the importance of determining both the frontal shape and propagation direction of the CME in interplanetary space; (3) the ICME was compressed in the radial direction while the longitudinal transverse size was extended.