The Sun at 30.4nm (extreme ultraviolet) on 8Mar2012 showing the large sunspot group AR1429, image credit NASA/SDO
When you want to see the stars, find someplace dark
The Sun at 30.4nm (extreme ultraviolet) on 8Mar2012 showing the large sunspot group AR1429, image credit NASA/SDO
XUV is roughly from 10 – 124 nm.
The XUV in question is more likely 30.4 nm which corresponds to the ionization of a single Helium electron into the so called He II state.
You are correct. Going back and reading the data for the image, they indicate 304 angstroms, which would be 30.4nm. Nice to know somebody noticed!