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  2. Stellar rotation - Wikipedia

    en.wikipedia.org/wiki/Stellar_rotation

    Stellar rotation is the angular motion of a star about its axis. The rate of rotation can be measured from the spectrum of the star, or by timing the movements of active features on the surface. The rotation of a star produces an equatorial bulge due to centrifugal force. As stars are not solid bodies, they can also undergo differential rotation.

  3. Galaxy rotation curve - Wikipedia

    en.wikipedia.org/wiki/Galaxy_rotation_curve

    Using data from the Spitzer Photometry and Accurate Rotation Curves (SPARC) database, a group has found that the radial acceleration traced by rotation curves (an effect given the name "radial acceleration relation") could be predicted just from the observed baryon distribution (that is, including stars and gas but not dark matter). [39]

  4. Celestial navigation - Wikipedia

    en.wikipedia.org/wiki/Celestial_navigation

    A diagram of a typical nautical sextant, a tool used in celestial navigation to measure the angle between two objects viewed by means of its optical sight. Celestial navigation, also known as astronavigation, is the practice of position fixing using stars and other celestial bodies that enables a navigator to accurately determine their actual current physical position in space or on the ...

  5. Polar coordinate system - Wikipedia

    en.wikipedia.org/wiki/Polar_coordinate_system

    An axis of rotation is set up that is perpendicular to the plane of motion of the particle, and passing through this origin. Then, at the selected moment t, the rate of rotation of the co-rotating frame Ω is made to match the rate of rotation of the particle about this axis, dφ/dt. Next, the terms in the acceleration in the inertial frame are ...

  6. 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 rotation; Stellar scintillation; Stellar seismology; Stellar spectra;

  7. Planisphere - Wikipedia

    en.wikipedia.org/wiki/Planisphere

    This usage continued into the Renaissance: for example Gerardus Mercator described his 1569 world map as a planisphere. In this article the word describes the representation of the star-filled celestial sphere on a flat disc. The first star chart to have the name "planisphere" was made in 1624 by Jacob Bartsch.

  8. Star chart - Wikipedia

    en.wikipedia.org/wiki/Star_chart

    A star chart drawn 5000 years ago by the Indians in Kashmir, which also depict a supernova for the first time in human history. [7] The Nebra sky disk , a 30 cm wide bronze disk dated to 1600 BC, bears gold symbols generally interpreted as a sun or full moon, a lunar crescent, several stars including the Pleiades cluster and possibly the Milky Way.

  9. Astrometry - Wikipedia

    en.wikipedia.org/wiki/Astrometry

    Concept art for the TAU spacecraft, a 1980s era study which would have used an interstellar precursor probe to expand the baseline for calculating stellar parallax in support of Astrometry. The history of astrometry is linked to the history of star catalogues , which gave astronomers reference points for objects in the sky so they could track ...