When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Star - Wikipedia

    en.wikipedia.org/wiki/Star

    A star is a luminous spheroid of plasma held together by self-gravity. [1] ... including such characteristics as luminosity, size, evolution, lifespan, and its ...

  3. Stellar classification - Wikipedia

    en.wikipedia.org/wiki/Stellar_classification

    In astronomy, stellar classification is the classification of stars based on their spectral characteristics. Electromagnetic radiation from the star is analyzed by splitting it with a prism or diffraction grating into a spectrum exhibiting the rainbow of colors interspersed with spectral lines.

  4. 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.

  5. Main sequence - Wikipedia

    en.wikipedia.org/wiki/Main_sequence

    where M and L are the mass and luminosity of the star, respectively, is a solar mass, is the solar luminosity and is the star's estimated main-sequence lifetime. Although more massive stars have more fuel to burn and might intuitively be expected to last longer, they also radiate a proportionately greater amount with increased mass.

  6. 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 ).

  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. Barnard's Star - Wikipedia

    en.wikipedia.org/wiki/Barnard's_Star

    Barnard's Star is a small red dwarf star in the constellation of Ophiuchus.At a distance of 5.96 light-years (1.83 pc) from Earth, it is the fourth-nearest-known individual star to the Sun after the three components of the Alpha Centauri system, and is the closest star in the northern celestial hemisphere. [15]

  9. Star cluster - Wikipedia

    en.wikipedia.org/wiki/Star_cluster

    Star clusters are large groups of stars held together by self-gravitation. Two main types of star clusters can be distinguished. Two main types of star clusters can be distinguished. Globular clusters are tight groups of ten thousand to millions of old stars which are gravitationally bound.