Multipoint coronal mass ejection events in solar cycle 25

Due to high solar activity, since the launch of Solar Orbiter about 5 years ago, at least 50 solar coronal mass ejection (CME) events have been observed at multiple spacecraft in situ, and more than 70 with at least one in situ and one imaging instrument. This type of measurement is of high importance for several reasons, which are relevant to improve both our basic understanding of the general nature of CMEs and to enhance our space weather forecasting capabilities. I will give an overview of the most important results so far using CME multipoint observations. They have been enabled by especially combining the in situ magnetic field observations made by Solar Orbiter, Parker Solar Probe, BepiColombo, near-Earth spacecraft at L1 and STEREO-A. We demonstrate how observations in the inner heliosphere allow us to create a power law for CME evolution seamlessly covering 0.07 to 5.4 au. We discuss results on flux rope coherence in interplanetary space, which is exceedingly relevant for understanding the 3D magnetic flux rope shape, and the applicability of upstream monitors for CME forecasting. Our living catalogs ICMECAT and LineupCAT for single and multipoint CME observations by various spacecraft are presented and are encouraged to be used by the research community. The most recent addition to the fleet of spacecraft enabling these groundbreaking observations is the PUNCH mission planned to be launched in February 2025, which enables polarized heliospheric imaging from Earth orbit. Here, new possibilities to derive the CME 3D structure in combination with in situ magnetic field observations of the same CME emerge.