This movie shows the way that the Extreme Ultraviolet Imager (EUI) instrument onboard Solar Orbiter studies the Sun – in this case zooming in on short-lived brightening events.
EUI is composed of three telescopes. The first is the Full Sun Imager (FSI) that can take images of the Sun’s full disc at extreme ultraviolet wavelengths of 17.4 nm and 30.4 nm. It is named FSI174/304. The two others are the High Resolution Imagers (HRIs). One works at a wavelength of 121.6 nm, which is an ultraviolet wavelength given out by hydrogen atoms, and is called HRILy-α. The other HRI works at 17.4 nm, like one of the two channels of the Full Sun Imager, and is dubbed HRIEUV. It images the Sun’s million-degree hot outer atmosphere, the corona, predominantly the emission from a highly ionised for of iron termed Fe IX and Fe X.
This movie begins with an FSI174 image of the Sun’s full disc taken on 23 February 2021 at 17:19:10 UT. It zooms in to show the area covered by the HRIEUV and then zooms in again to show the sequence of images taken every two seconds by this instrument until 17:20:32 UT. Careful inspection of the images shows ‘small’ short-lived brightening events. Although they look small, these events are shooting out jets of electrified gas, called plasma, over a distance of several thousand kilometres, at speeds of a hundred kilometres per second.