csillagbesorolásuk

Csillagbesorolásuk refers to the classification of stars based on their spectral characteristics. This system, largely developed by astronomers at the Harvard College Observatory in the early 20th century, categorizes stars by their surface temperature and, consequently, their color. The primary spectral classes are O, B, A, F, G, K, and M, ordered from hottest to coolest. Each class is further subdivided by a number from 0 to 9, where 0 represents the hottest stars within a class and 9 the coolest.

The spectral type is determined by analyzing the star's spectrum, which reveals the absorption lines of various elements present in its atmosphere. The strength and pattern of these lines are highly dependent on the star's temperature. For example, O-type stars, which are extremely hot, exhibit lines of ionized helium, while cooler M-type stars show strong molecular bands, particularly of titanium oxide.

Beyond temperature, spectral classification also provides clues about a star's luminosity and evolutionary stage. While the primary classification is spectral type, a more comprehensive system, the Yerkes spectral classification or MKK system, also includes luminosity classes (Roman numerals I to V) indicating whether a star is a supergiant, bright giant, giant, subgiant, or main-sequence star. This dual classification allows astronomers to better understand a star's physical properties and its place within the Hertzsprung-Russell diagram. Csillagbesorolásuk is therefore a fundamental tool in stellar astronomy.