  The whole sky differential star counts (DSC) with 1 degree resolution are
retrieved from 2MASS online data service. Galaxy with double exponential thin
and thick disks and a single power law luminosity function (LF) is used to
interpret the 2MASS data. The slope of the DSC appears roughly isotropic over
the whole sky, the average value is ~0.32, which corresponds to a power law
index ~1.8 of the LF. We find that the scale-length and scale-height the thin
disk are ~3.0 kpc and ~245 pc, and those of the thick disk are ~3.0 kpc and
~780 pc. The ratio of the thick disk to the thin disk is ~7%. The location of
Sun above the disk is ~15 pc. A comparison of the data and model and their
discrepancy are also provided.
