Nyájtípus

Nyájtípus refers to a classification system used to categorize different types of spectral lines emitted or absorbed by celestial objects. This system is primarily based on the excitation and ionization states of atoms present in the object's atmosphere. When light from a star passes through its atmosphere, certain wavelengths are absorbed at specific temperatures, creating dark lines in the spectrum. Conversely, when atoms in a hot gas are excited and then return to a lower energy state, they emit light at specific wavelengths, creating bright lines.

The Nyájtípus classification is particularly useful in stellar astronomy for determining a star's surface temperature. Different temperature ranges favor different atomic processes. For example, at very low temperatures, molecules can form and their spectral lines become prominent. As temperature increases, molecules dissociate, and atomic lines begin to dominate. At even higher temperatures, atoms become ionized, and the spectral lines of ions appear.

Astronomers observe the spectral lines present in a celestial object's light and compare them to known patterns associated with various Nyájtípus categories. This comparison allows them to infer the physical conditions, such as temperature and chemical composition, of the object. While the term "Nyájtípus" itself is not a standard widely recognized scientific term in English-language astronomy literature, the underlying concept of classifying spectra based on atomic excitation and ionization is fundamental to astrophysics and is encompassed by established spectral classification systems like the Morgan-Keenan (MK) system.