The evolution of CNO elements in galaxies

Understand

After hydrogen and helium, oxygen, carbon, and nitrogen - hereinafter, the CNO elements - are the most abundant species in the universe.

• They are observed in all kinds of astrophysical environments, from the smallest to the largest scales, and are at the basis of all known forms of life, hence, the constituents of any biomarker.
• As such, their study proves crucial in several areas of contemporary astrophysics, extending to astrobiology.
• In this review, I will summarize current knowledge about CNO element evolution in galaxies, starting from our home, the Milky Way.