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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

    The rotation curve of a disc ... When mass profiles of galaxies are calculated from the distribution of stars in spirals and mass-to-light ratios in the stellar ...

  4. Sidereal time - Wikipedia

    en.wikipedia.org/wiki/Sidereal_time

    The slightly longer stellar period is measured as the Earth rotation angle (ERA), formerly the stellar angle. [4] An increase of 360° in the ERA is a full rotation of the Earth. A sidereal day on Earth is approximately 86164.0905 seconds (23 h 56 min 4.0905 s or 23.9344696 h).

  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 remnant; Stellar rotation; Stellar scintillation; Stellar seismology;

  6. Light curve - Wikipedia

    en.wikipedia.org/wiki/Light_curve

    Shows just over one full rotation, which lasts 3.7474 hours. In astronomy, a light curve is a graph of the light intensity of a celestial object or region as a function of time, typically with the magnitude of light received on the y-axis and with time on the x-axis. The light is usually in a particular frequency interval or band.

  7. Proper motion - Wikipedia

    en.wikipedia.org/wiki/Proper_motion

    For example, the proper motion results in right ascension in the Hipparcos Catalogue (HIP) have already been converted. [12] Hence, the individual proper motions in right ascension and declination are made equivalent for straightforward calculations of various other stellar motions. The position angle θ is related to these components by: [2] [13]

  8. Rossiter–McLaughlin effect - Wikipedia

    en.wikipedia.org/wiki/Rossiter–McLaughlin_effect

    J. R. Holt in 1893 proposed a method to measure the stellar rotation of stars by using radial velocity measurements. He predicted that when one star of an eclipsing binary eclipsed the other, it would first cover the advancing blueshifted half and then the receding redshifted half.

  9. Galactic coordinate system - Wikipedia

    en.wikipedia.org/wiki/Galactic_coordinate_system

    Since as defined the galactic coordinate system does not rotate with time, Sgr A* is actually decreasing in longitude at the rate of galactic rotation at the sun, Ω, approximately 5.7 milliarcseconds per year (see Oort constants).