binary star that can be distinguished from a single star only through analysis of the Doppler shift of the spectral lines of one or both stars as they revolve about their common center of mass.
A binary star in which the two stars are too close to be seen as separate stars, but can be detected through a careful examination of the spectrum. Usually detected through changes in the Doppler shift of spectral lines.
double star whose components are not observed separately in a telescope but whose binary character is revealed by the periodic Doppler shift of spectral lines.
two stars orbiting a common point at too great a distance away from us to resolve the two stars individually, but whose binary nature is indicated in the periodic shift of their spectral lines as they orbit around each other.
a binary in which two stars are so close together that they cannot be seen separately, but their separate light spectra can be distinguished by a spectroscope
A binary system detected by Doppler shifts in its spectral lines is called a spectroscopic binary. Analysis of the spectral line shifts versus time reveals information about the radial velocities of the component stars. In spectroscopic binaries the component stars are often very close and may in fact exchange material due to tidal interactions. Orbital periods range from a few hours to months, with separations of much less than an AU in many cases. The first spectroscopic binary detected was Mizar A.
A binary-star system which from Earth appears as a single star, but is known to contain more than one star because of the back-and-forth Doppler shifts that are observed as the two stars orbit one another. another.
A star system in which the stars are too close together to be visible separately. We see a single point of light, and only by taking a spectrum can we determine that there are two stars.
