SESSION Space for everyone

Hydrogen is the most abundant element in the Universe. 9 out of 10 atoms are hydrogen atoms, accounting for 74% of the mass of "ordinary" matter, also known as baryonic matter. Its presence is significant not only for the formation of stars and galaxies but also for studying their evolution. In astronomy, hydrogen is used as a marker to identify various cosmic regions and structures, thanks to its characteristic spectral lines. In the Solar System - our closest environment - hydrogen is the dominant element. It allows us to study the Sun, planetary atmospheres, and comets, enabling a better understanding of the physical processes occurring in these celestial bodies.

Unfortunately, all astronomical observations are often hindered by artificial light pollution, limiting the possibilities for space research. However, thanks to continuous technological development and growing awareness of various forms of dark sky protection, scientists are making efforts to mitigate this problem. This translates into the advancement of astronomy, including a fuller understanding of the role of hydrogen in the distant and nearby Universe.