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The Extreme Ultraviolet Imager (EUI) is part of the remote sensing instrument package of the ESA/NASA Solar Orbiter mission. EUI aims at improving scientific understanding of the structure and dynamics of the solar atmosphere, globally as well as at high resolution, and from high solar latitude perspectives. EUI consists of 3 telescopes that are optimized to image in Lyman-α and EUV (17.4 nm, 30.4 nm) to provide a coverage from chromosphere up to corona. 

EUI News


Spot the moss, spicules, and coronal rain

The EUI instrument onboard Solar Orbiter observed the solar corona in exquisite detail once more.

New Guest Investigator Call: visit the EUI and SWAP/LYRA PI teams in Brussels in 2024!

The EUI and SWAP/LYRA PI teams welcome research proposals for the 2024 round of its Guest Investigator Program for research based on EUI, SWAP or LYRA data.

Solar Orbiter Discovers Tiny Jets That Could Power the Solar Wind

ESA’s Solar Orbiter spacecraft has discovered a multitude of tiny jets of material escaping from the Sun’s outer atmosphere. Each jet lasts for between 20 and 100 seconds, and expels plasma at around 100 km/s. These jets could be the long-sought-after source of the ‘solar wind’.

Heat waves on the Sun

A joint scientific team led by the Royal Observatory of Belgium (ROB) and the KU Leuven has found that high-frequency magnetic waves could play an essential role in keeping the Sun’s atmosphere at millions of degrees. This finding sheds a new light on the most intriguing solar mystery: what makes the Sun’s atmosphere hotter than its surface?

EUI can observe both elephants and mice among solar eruptions

The EUI telescope on Solar Orbiter was able to catch the miniature version of solar flares and mass ejections. Thanks to sharp and fast imaging of the EUI telescope, researchers could observe magnetic reconnection taking place repeatedly on very small scales.

EUI detects high-frequency sideways waves

High-frequency sideways waves were detected for the first time using Europe's new solar observatory Solar Orbiter. These sideways waves are much more energetic than previously observed waves, and could play a role in heating the solar corona.

Mercury, a little black dot on the Sun

The telescope EUI onboard the satellite Solar Orbiter could capture Mercury while it transited the Sun. Scientists use the little black as a guide for science-approved photo-editing.

Solar snake spotted slithering across Sun’s surface

Solar Orbiter has spotted a ‘tube’ of cooler atmospheric gases snaking its way through the Sun’s magnetic field. The observation provides an intriguing new addition to the zoo of features revealed by the ESA-led Solar Orbiter mission, especially since the snake was a precursor to a much larger eruption.