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  2. Fraunhofer lines - Wikipedia

    en.wikipedia.org/wiki/Fraunhofer_lines

    The Fraunhofer lines are typical spectral absorption lines. Absorption lines are narrow regions of decreased intensity in a spectrum, which are the result of photons being absorbed as light passes from the source to the detector. In the Sun, Fraunhofer lines are a result of gas in the Sun's atmosphere and outer photosphere. These regions have ...

  3. K-type main-sequence star - Wikipedia

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

    K-type main-sequence stars are about three to four times as abundant as G-type main-sequence stars, making planet searches easier. [17] K-type stars emit less total ultraviolet and other ionizing radiation than G-type stars like the Sun (which can damage DNA and thus hamper the emergence of nucleic acid based life). In fact, many peak in the red.

  4. Spectral line - Wikipedia

    en.wikipedia.org/wiki/Spectral_line

    A spectral line is a weaker or stronger region in an ... such as K for a line at 393.366 nm emerging from ... looking east with the sun to the west at around 3–4 pm ...

  5. Stellar classification - Wikipedia

    en.wikipedia.org/wiki/Stellar_classification

    G-type stars, including the Sun, [14] have prominent spectral lines H and K of Ca II, which are most pronounced at G2. They have even weaker hydrogen lines than F, but along with the ionized metals, they have neutral metals. There is a prominent spike in the G band of CN molecules. Class G main-sequence stars make up about 7.5%, nearly one in ...

  6. List of nearest stars by spectral type - Wikipedia

    en.wikipedia.org/wiki/List_of_nearest_stars_by...

    Below there are lists the nearest stars separated by spectral type. The scope of the list is still restricted to the main sequence spectral types: M, K, F, G, A, B and O. It may be later expanded to other types, such as S, D or C. The Alpha Centauri star system is the closest star system to the Sun.

  7. Stellar corona - Wikipedia

    en.wikipedia.org/wiki/Stellar_corona

    The K-corona (K for kontinuierlich, "continuous" in German) is created by sunlight Thomson scattering off free electrons; doppler broadening of the reflected photospheric absorption lines spreads them so greatly as to completely obscure them, giving the spectral appearance of a continuum with no absorption lines.

  8. Solar analog - Wikipedia

    en.wikipedia.org/wiki/Solar_analog

    The Sun is a 4.6 billion year-old G-class (G2V) star and is more massive than 95% of all stars. Only 7.6% are G-class stars. The stars below are more similar to the Sun and having the following qualities: [1] Temperature within 50 K from that of the Sun (5728 to 5828 K) [a] (within 10 K of sun (5768–5788 K)).

  9. Sun - Wikipedia

    en.wikipedia.org/wiki/Sun

    The Sun is 1.4 million kilometers (4.643 light-seconds) wide, about 109 times wider than Earth, or four times the Lunar distance, and contains 99.86% of all Solar System mass. The Sun is a G-type main-sequence star that makes up about 99.86% of the mass of the Solar System. [26]