The stellar content of the eROSITA all-sky survey

The eROSITA instrument onboard the Russian-German SRG mission has so far completed more than four all-sky surveys and detected millions of new X-ray sources. Coronal X-ray sources, i.e. X-ray emitters similar to our Sun, constitute a significant fraction of the overall eROSITA source count, yet these X-ray detected stars have properties quite different from those found for the Sun. X-ray emission is the most important proxy indicator for “stellar magnetic activity”, hence an X-ray survey like that of eROSITA provides insights into the youth of the Sun, when it was as “magnetically active” as the vast majority of the eROSITA detected stellar X-ray sources. The availability of precise astrometry from the Gaia satellite allows the complete identification of the stellar X-ray sky including an age assessment of the underlying sources.

I will discuss and highlight these new research opportunities by providing recent eROSITA results on the Sco-Cen star forming region and very energetic eruptions from young stars.