EGU General Assembly 2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

A potential near real-time algorithm for CME propagation utilizing heliospheric imaging observations

Evangelos Paouris1 and Angelos Vourlidas2
Evangelos Paouris and Angelos Vourlidas
  • 1National Observatory of Athens, Institute for Astronomy, Astrophysics, Space Applications and Remote Sensing, Penteli, Athens, Greece (
  • 2Applied Physics Laboratory, The Johns Hopkins University, Laurel, MD 20723, USA

The estimation of the Coronal Mass Ejection (CME) arrival at Earth is an open issue in the field of Space Weather. We present a new near real-time algorithm based on heliospheric imaging (HI) observations of the CME front as a function of time. First, we transform the front elongation angle into radial distance using basic stereoscopic techniques (i.e. fixed-phi, harmonic mean and self-similar expansion). Then we adopt the assumptions that (1) CME accelerate (or decelerate) from the Sun up to some distance and (2) they move with a constant speed past that distance. This “two-phase kinematics” behavior forms the core of our algorithm. The resulting kinematic profiles provide estimates of the CME Time-of-Arrival (ToA) and Speed-on-Arrival (SoA) at 1 AU. This new tool is tested on a sample of CMEs where stereoscopic views were possible, from the STEREO-A and -B HIs were available. The algorithm is promising with predictions for the ToA of CMEs of the order of ±1 hour and for SoA of ±100 km/s. Our approach is in preparation for a possible future combination of HI data from missions at L5. We will test our method further for cases beyond the 1 AU studying ICMEs which has been spotted also on Mars (1.52 AUs).

How to cite: Paouris, E. and Vourlidas, A.: A potential near real-time algorithm for CME propagation utilizing heliospheric imaging observations, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-11702,, 2022.

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