Multi-spacecraft Observations of the Evolution of Interplanetary Coronal Mass Ejections between 0.3 and 2.2 au: Conjunctions with the Juno Spacecraft

Abstract

We present a catalog of 35 interplanetary coronal mass ejections (ICMEs) observed by the Juno spacecraft and at least one other spacecraft during its cruise phase to Jupiter. We identify events observed by MESSENGER, Venus Express, Wind, and STEREO with magnetic features that can be matched unambiguously with those observed by Juno. A multi-spacecraft study of ICME properties between 0.3 and 2.2 au is conducted: we first investigate the global expansion by tracking the variation in magnetic field strength with increasing heliocentric distance of individual ICME events, finding significant variability in magnetic field relationships for individual events in comparison with statistical trends. With the availability of plasma data at 1 au, the local expansion at 1 au can be compared with global expansion rates between 1 au and Juno. Despite following expected trends, the local and global expansion rates are only weakly correlated. Finally, for those events with clearly identifiable magnetic flux ropes, we investigate the orientation of the flux rope axis as they propagate; we find that 64% of events displayed a decrease in inclination with increasing heliocentric distance, and 40% of events undergo a significant change in orientation as they propagate toward Juno. The multi-spacecraft catalog produced in this study provides a valuable link between ICME observations in the inner heliosphere and beyond 1 au, thereby improving our understanding of ICME evolution.

Characteristic Scales of Complexity and Coherence within Interplanetary Coronal Mass Ejections: Insights from Spacecraft Swarms in Global Heliospheric Simulations

“…We note this definition of complexity is solely based on the magnetic field signatures associated with a given ME, and it does not take into account any plasma information nor the properties of its preceding shock and sheath. This choice was made to be consistent with observational works in the past ∼15 yr, which could only make use of magnetic field data at distances other than 1 au (Winslow et al 2016(Winslow et al , 2021bDavies et al 2022;Scolini et al 2022). However, it will be important for future investigations of ICME complexity to asses them holistically, i.e., by looking at changes in all aspects of the ICME as opposed to just the magnetic parameters within the ME, to understand complexity changes from a more fundamental standpoint.…”

“…In this section, we focus on spacecraft near the CME equatorial plane (which is close to the solar equatorial and ecliptic planes in our particular case) in order to support the planning and interpretation of observations by future multispacecraft missions exploring ICME structures in the ecliptic plane. The simulation setup considered here specifically applies to spacecraft in the near-ecliptic region that cross through lowinclination FRs, which constitute about half of the ME FR configurations detected within 1 au (e.g., Lepping et al 1990;Bothmer & Schwenn 1998;Lynch et al 2003), and the majority of cases observed between 1 and 2.2 au (Davies et al 2022).…”

“…This has led to the proliferation of flux-rope (FR) models to describe the ME local and global magnetic structure (see, e.g., Lepping et al 1990;Mulligan & Russell 2001;Marubashi & Lepping 2007;Hidalgo & Nieves-Chinchilla 2012;Hidalgo 2013;Isavnin 2016;Nieves-Chinchilla et al 2016, 2018aWeiss et al 2021). FR models have also been successful in describing the CME preeruptive and eruptive configuration, early evolution in the solar corona, and interplanetary evolution up to Mars and beyond (e.g., Vourlidas 2014;Patsourakos et al 2020;Palmerio et al 2021;Davies et al 2022).…”

Global Morphology Distortion of the 2021 October 9 Coronal Mass Ejection from an Ellipsoid to a Concave Shape

“…When spacecraft at different heliospheric distances are near radially aligned, they have the opportunity to measure the same CME. This makes the case studies and statistical studies of a CME's radial evolution feasible (Burlaga et al 1981;Cane et al 1997;Liu et al 2005Liu et al , 2008Möstl et al 2012;Ruffenach et al 2012;Good et al 2015;Li et al 2017;Wang et al 2018;Good et al 2019;Chi et al 2020Chi et al , 2021Lugaz et al 2020;Salman et al 2020;Davies et al 2021Davies et al , 2022Winslow et al 2021aWinslow et al , 2021bLugaz et al 2022;Möstl et al 2022;Réville et al 2022;Scolini et al 2022;Xu et al 2022;Zhang 2022;Zhao et al 2022). Using combined, multipoint observations of the same magnetic clouds by STEREO-A, STEREO-B, ACE, Wind, and THEMIS, Ruffenach et al (2012) confirmed the occurrence of magnetic cloud erosion during their propagation from the Sun to Earth.…”

Tracking magnetic flux and helicity from the Sun to Earth

“…In general, ICMEs tend to expand self-similarly in the radial direction (e.g., Vršnak et al 2019). Therefore, the increase in their size as well as the correspond-ing decrease in the magnetic field strength can be described by a power-law function (Bothmer & Schwenn 1998;Leitner et al 2007;Démoulin et al 2008;Gulisano et al 2010;Good et al 2019;Salman et al 2020;Davies et al 2022). Observational studies constrain the size and magnetic field power-law indices to 0.45 < n a < 1.14 and −1.89 < n B < −0.88, respectively (e.g., Gulisano et al 2012).…”