The Sun’s corona is comparable to the Earth’s atmosphere. What makes it special is that the outermost layer is not only extremely hot but – outshone by the Sun’s light – difficult to see. “The complete coverage during a solar eclipse reveals a bright ring with rays. Much like in simple drawings of the Sun,” explains Manuela Temmer.
In addition, massive coronal mass ejections occur in the corona, during which large quantities of plasma are hurled into space. These can influence the Earth’s magnetic field and disrupt satellites, air traffic and mobile phone reception.
“Although technology is highly advanced, no device can currently reveal the fine structures of the corona any better than a total solar eclipse,” emphasises Temmer. The catch is that the observation window is often very short, making it difficult to observe the dynamics of the corona.
PhD students in Spain
This year, the total solar eclipse should be clearly visible in Spain. A number of physics students from the University of Graz have also travelled to the Iberian Peninsula specifically for this event. Among them is Amaia Razquin Lizarraga. The physics PhD student, supervised by astrophysicist Astrid Veronig, is researching solar flares and coronal dimmings. She has travelled to Arguedas, a small town in the northern Spanish region of Navarra. There, Razquin Lizarraga is not only meeting her family but, probably together with her University of Graz colleague Thierry Fox, she is also taking part in an event to mark the solar eclipse. “We will be carrying out our activities as part of an event organised by the Government of Navarra and will be collaborating with other early-career researchers from the European Geosciences Union and the Lunar Explorers Society. Up to 2,000 visitors are expected,” explains Amaia Razquin Lizarraga.
Observation on the Schloßberg
Even though solar research is her main focus, a solar eclipse fascinates even renowned scientists. Manuela Temmer and Astrid Veronig will be observing the phenomenon from the Schloßberg in Graz on the evening of 12 August.
The astrophysicists will be there alongside fellow experts to answer questions from the public. The Institute of Physics at the University of Graz has also set up five telescopes and provided special viewing glasses, through which members of the public can catch a glimpse of the eclipsed sun.
Between 7.30 pm and 8.15 pm in Graz – weather permitting – the moon is expected to cover up to 85 per cent of the sun.