Changes in the Properties of Coronal Mass Ejection During Propagation That May Affect Their Imapct on Planetary Magnetospheres

Coronal mass ejections (CMEs) are the primary driver of intense geomagnetic effects, not only at Earth, but at most planets in the solar system. As CMEs propagate, their properties change due to the interaction with the solar wind, corotating streams or interaction regions (CIRs), and other transients, affecting their probability of impacting a given planet, their predicted arrival time and geomagnetic potential. In the rare cases, when the same CME is observed in situ by two or more spacecraft at different locations in the heliosphere, these changes can be directly measured and studied; else, one relies on numerical simulations and remote observations to deduce how heliospheric propagation modifies CME properties. Here, we review some recent studies relating the changes in CME properties during their propagation with their effects on planets, focusing primarily on the interaction of successive CMEs and the interaction of CMEs with CIRs.