and

We use the star counts model of Ortiz & Lépine (1993) to perform an unprecedented ex-ploration of the most important galactic parameters comparing the predicted counts with the 2MASS observed star counts in the J, H and KS bands for a grid of positions covering the whole sky. The comparison is made using a grid of lines-of-sight given by the HEALPix pixelization scheme. The resulting best fit values for the parameters are: (2120±200) pc for the radial scale length and (205±40) pc for the scale height of the thin disk, with a central hole of (2070+2000−800) pc for the same disk; (3050±500) pc for the radial scale length and (640±70) pc for the scale height of the thick disk; (400±100) pc for the central dimension of the spheroid, (0.0082±0.0030) for the spheroid to disk density ratio, and (0.57±0.05) for the oblate spheroid parameter. Subject headings: Galaxy: fundamental parameters — Galaxy: structure — infrared: stars — stars: statistics 1