============================= hip_OB.README =========================================

The file hip_OB.dat includes 9372 bright OB stars selected from the Hipparcos catalogue.
For each source, we provide:

 l (deg)         b (deg)       Plx (mas)     e_Plx (mas)    d_Mt (pc)      d_SK (pc)   
 
 where:
 
 l, b are the galactic coordinates in degrees
 
 Pxl and e_Plx are the trigonometric parallax and its error, in milliarcseconds
 
 d_Mt is the spectro-photometric distance in parsecs, as derived from the calibrations 
      of the O stars by Martins, Schaerer & Hillier, 2005, Astron. & Astrophys., 436, 1049

 d_SK is the spectro-photometric distance in parsecs, as derived from the calibrations by 
      Schmidt-Kaler Th., 1982, in Schaifers K., Voigt H. H., eds, 
	  Landolt-B?ornstein, group VI, Vol 2, subvol. b, Stars and Star Clusters. 
	  
null field: -9999


Contact:  A. Spagna (INAF-OATo, Torino)  spagna@oato.inaf.it
	  
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