Search results
Results From The WOW.Com Content Network
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.
Thus the magnitude of the galaxy rotation is related to the galaxy's visible mass. [21] While precise fitting of the bulge, disk, and halo density profiles is a rather complicated process, it is straightforward to model the observables of rotating galaxies through this relationship.
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.
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]
Pages Related to Stellar properties, Pages using the word stellar in a physics context. ... Stellar remnant; Stellar rotation; Stellar scintillation; Stellar seismology;
Illustration of the use of interferometry in the optical wavelength range to determine precise positions of stars. Courtesy NASA/JPL-Caltech. Astrometry is a branch of astronomy that involves precise measurements of the positions and movements of stars and other celestial bodies.
The viewer is situated at the bottom. Light from the anticlockwise-rotating star is blue-shifted on the approaching side, and red-shifted on the receding side. As the planet passes in front of the star it sequentially blocks blue- and red-shifted light, causing the star's apparent radial velocity to change, but it does not in fact change.
The horizontal branch (HB) is a stage of stellar evolution that immediately follows the red-giant branch in stars whose masses are similar to the Sun's. Horizontal-branch stars are powered by helium fusion in the core (via the triple-alpha process) and by hydrogen fusion (via the CNO cycle) in a shell surrounding the core.