The Eruption of 22 April 2021 as Observed by Solar Orbiter: Continuous Magnetic Reconnection and Heating After the Impulsive Phase

We report on one of the first solar-eruptive events that was simultaneously observed by three of the remote-sensing instruments onboard Solar Orbiter during the cruise phase. The Extreme Ultraviolet Imager (EUI) observed an eruption on 22 April 2021. The corresponding CME was recorded by the coronagraph Metis. Finally, the Spectrometer/Telescope for Imaging X-rays (STIX) sampled the associated X-ray flare, which was partially occulted. From the Earth, the eruption-source region was observed close to disk center. We provide an analysis of the eruption as observed by these various instruments. In particular, we show that in this eruption, continuous magnetic reconnection and heating have to be present even well after the impulsive phase. The need for this is derived from multiple independent lines of evidence - using both flare and CME observations - that have not been reported before for a single event. The combination of data from Solar Orbiter, as well as other space-based assets, clearly showcases the scientific potential for the science phase of Solar Orbiter, and the unique observations available.

Automated summary

We report on a solar-eruptive event that was observed simultaneously by three remote-sensing instruments onboard Solar Orbiter. The eruption was observed by the Extreme Ultraviolet Imager, the corresponding CME was recorded by the coronagraph Metis, and the associated X-ray flare was sampled by the Spectrometer/Telescope for Imaging X-rays. Analysis of the data from these instruments revealed the presence of continuous magnetic reconnection and heating even after the impulsive phase, which has not been reported before for a single event. These observations highlight the scientific potential of Solar Orbiter and other space-based assets.