accretion disc
61Dark star (Newtonian mechanics) — This article is about astronomical objects described by Newtonian mechanics. For the modern concept based on dark matter, see dark star (dark matter). For the modern concept based on dark energy, see dark energy star. A dark star is a theoretical …
62Stellar kinematics — is the study of the movement of stars without needing to understand how they acquired their motion. This differs from stellar dynamics, which takes into account gravitational effects. The motion of a star relative to the Sun can provide useful… …
63Moons of Uranus — Uranus and its six largest moons compared at their proper relative sizes and relative positions. From left to right: Puck, Miranda, Ariel, Umbriel, Titania and Oberon Uranus, the seventh planet of the Solar System, has 27 known moons …
64Apparent magnitude — Asteroid 65 Cybele and 2 stars with their magnitudes labeled The apparent magnitude (m) of a celestial body is a measure of its brightness as seen by an observer on Earth, normalized to the value it would have in the absence of the atmosphere.… …
65Main sequence — A Hertzsprung Russell diagram plots the actual brightness (or absolute magnitude) of a star against its color index (represented as B V). The main sequence is visible as a prominent diagonal band that runs from the upper left to the lower right.… …
66List of nearest stars — Artist s conception of a red dwarf star, the most common type of star in the Sun s stellar neighborhood, and in the universe. Although termed a red dwarf, the surface temperature of this star would give it an orange hue when viewed from close… …
67Star designation — Designations of stars (and other celestial bodies) are done by the International Astronomical Union (IAU). Many of the star names in use today were inherited from the time before the IAU existed. Other names, mainly for variable stars (including… …
68Stellar classification — In astronomy, stellar classification is a classification of stars based on their spectral characteristics. The spectral class of a star is a designated class of a star describing the ionization of its chromosphere, what atomic excitations are… …
69Proper motion — The proper motion of a star is its angular change in position over time as seen from the center of mass of the solar system.[1] It is measured in seconds of arc per year, arcsec/yr, where 3600 arcseconds equal one degree.[2] This contrasts with… …
70Chromosphere — The Sun observed through a telescope with an H alpha filter …
