Predicted star counts and mean parallaxes down to the 23rd magnitude
Abstract
Star counts and mean parallaxes as a function of B,V,R magnitudes down to 23 are presented. The data were computed by the use of two fundamental equations of stellar statistics. The assumed model considers the Galaxy as a symmetrical system with respect to its rotation axis and to its equatorial plane and as composed of the thin disk (main sequence and red giants), the thick disk and spheroid populations. Numbers of stars and mean parallaxes were derived in bins of galactic longitude and latitude of 30(deg) and 10(deg) , respectively. For the computation of the mean parallaxes depending on Galactic coordinates and magnitudes, series of products of Hermite and Legendre polynomials and of Fourier terms were used. The results of this paper may help in the planning of future survey missions and in the design of new telescopes. In addition, mean parallaxes can be used to derive corrections to absolute parallaxes and proper motions for any position in the sky.
 Publication:

Astronomische Nachrichten
 Pub Date:
 April 1997
 DOI:
 10.1002/asna.2113180304
 Bibcode:
 1997AN....318..163K