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  2. Stellar classification - Wikipedia

    en.wikipedia.org/wiki/Stellar_classification

    The modern classification system is known as the Morgan–Keenan (MK) classification. Each star is assigned a spectral class (from the older Harvard spectral classification, which did not include luminosity [1]) and a luminosity class using Roman numerals as explained below, forming the star's spectral type.

  3. Cosmic distance ladder - Wikipedia

    en.wikipedia.org/wiki/Cosmic_distance_ladder

    By measuring these properties from a star's spectrum, the position of a main sequence star on the H–R diagram can be determined, and thereby the star's absolute magnitude estimated. A comparison of this value with the apparent magnitude allows the approximate distance to be determined, after correcting for interstellar extinction of the ...

  4. B-type main-sequence star - Wikipedia

    en.wikipedia.org/wiki/B-type_main-sequence_star

    This class of stars was introduced with the Harvard sequence of stellar spectra and published in the Revised Harvard photometry catalogue. The definition of type B-type stars was the presence of non-ionized helium lines with the absence of singly ionized helium in the blue-violet portion of the spectrum. All of the spectral classes, including ...

  5. List of stellar properties - Wikipedia

    en.wikipedia.org/wiki/List_of_stellar_properties

    Pages Related to Stellar properties, Pages using the word stellar in a physics context. Stellar aberration; Stellar age estimation; Stellar archaeology

  6. Initial mass function - Wikipedia

    en.wikipedia.org/wiki/Initial_mass_function

    For example, the initial mass of a star is the primary factor of determining its colour, luminosity, radius, radiation spectrum, and quantity of materials and energy it emitted into interstellar space during its lifetime. [1] At low masses, the IMF sets the Milky Way Galaxy mass budget and the number of substellar objects that form.

  7. A-type main-sequence star - Wikipedia

    en.wikipedia.org/wiki/A-type_main-sequence_star

    The revised Yerkes Atlas system [7] listed a dense grid of A-type dwarf spectral standard stars, but not all of these have survived to this day as standards. The "anchor points" and "dagger standards" of the MK spectral classification system among the A-type main-sequence dwarf stars, i.e. those standard stars that have remained unchanged over years and can be considered to define the system ...

  8. G-type main-sequence star - Wikipedia

    en.wikipedia.org/wiki/G-type_main-sequence_star

    A G-type main-sequence star (spectral type: G-V), also often, and imprecisely, called a yellow dwarf, or G star, is a main-sequence star (luminosity class V) of spectral type G. Such a star has about 0.9 to 1.1 solar masses and an effective temperature between about 5,300 and 6,000 K (5,000 and 5,700 °C; 9,100 and 10,000 °F). Like other main ...

  9. K-type main-sequence star - Wikipedia

    en.wikipedia.org/wiki/K-type_main-sequence_star

    A K-type main-sequence star, also referred to as a K-type dwarf, or orange dwarf, is a main-sequence (hydrogen-burning) star of spectral type K and luminosity class V. These stars are intermediate in size between red M-type main-sequence stars ("red dwarfs") and yellow/white G-type main-sequence stars .