Snapshot of a solar campfire, generated in a computer simulation, and its relation to the local magnetic field. The two images show the campfire – a small, flickering brightening – during and after the brightening event, respectively. Campfires were discovered by ESA’s Solar Orbiter mission in 2020.
In both images the left panel shows a simulated view of emission from the Sun’s corona, as would be seen by Solar Orbiter’s Extreme Ultraviolet Imager. The right panel shows the corresponding magnetic field as a magnetogram, where black and white are opposite polarities, and grey is zero field. Overplotted on the magnetogram are selected field lines in different colours.
In the first image field lines from the bottom-right white magnetic patch are seen stretching up to the top left. In the second snapshot these field lines have been “eaten-up” by reconnection, a process whereby field lines break and then reconnect, releasing energy when they do so.
Modelling shows that the energy released from the brightenings through component reconnection may be enough to maintain the temperature of the solar corona predicted from observations.