Spectroscopic Parallax
The term spectroscopic parallax is a misnomer as it actually has nothing to do with parallax. It is, however, a way to find the distance to stars.
SPECTROSCOPIC PARALLAX
In Chapter 2 we introduced the first "rung" on a ladder of distance-measurement techniques that will ultimately carry us to the edge of the observable universe. That rung is radar ranging on the inner planets.
Spectroscopic Parallax
You can use the correlation between luminosity and temperature (spectral type) for main sequence stars to get their distances.
spectroscopic parallax Method of determining the distance to a star by measuring its temperature and then determining its absolute brightness by comparing with a standard H—R diagram.
spectroscopic parallax
A method of determining distances to stars by comparing their absolute and apparent brightnesses.
spectroscopy
The study of stellar spectra in order to determine the chemical composition of stars.
Spectroscopic Parallax
Parallax for a group of stars based on the magnitudes and spectral types of the member stars. Spectroscopic parallax is by far the most common method of determining stellar distances.
Spectroscopy ...
spectroscopic parallax: The method of determining a star's distance by comparing its apparent magnitude with its absolute magnitude as estimated from its spectrum.
spectroscopic parallax - (n.)
The distance to a star derived from comparison of its apparent magnitude with its absolute magnitude deduced from study of its position on an H-R diagram determined by observation of its spectrum (spectral type and ...
Spectroscopic Parallax: Something of a misnomer, this process doesn't really involve parallax at all, but it is a way to get distances. One uses the observed spectrum of the star to obtain the spectral type and luminosity class.
called "spectroscopic parallax".
Further methods, mostly of the standard candle variety, are the variable stars called Cepheids — the absolute brightness of which depends on their observed period of variation —, supernova brightnesses, ...
Once the H-R diagram was popularized, a new method of determining the distances to stars was found - that of spectroscopic parallax. Actually, this is a rather confusing term, since there is no parallax angle measured.
Contrary to the CNS2 (Gliese 1969) trigonometric parallaxes and photometric or spectroscopic parallaxes were not combined.
Then we can look at more distant clusters and use the process of main-sequence fitting, or spectroscopic parallax to obtain a distance.
Parallax for a group of stars based on the magnitudes and spectral types of the member stars. Spectroscopic parallax is by far the most common method of determining stellar distances. [H76]
Spectroscopy ...
Spectroscopic parallax is the most widely used technique for determining the distances of stars that are too distant for their stellar parallaxes to be measured.
spectroscopic parallax: the distance obtained by observing a star's color, correcting for Doppler shift, inferring the star's luminosity from a calibrated HR diagram, and calculating distance based on the observed flux.
 See also: Distance, Parallax, Star, Sun, Galaxy
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