We present bright galaxy number counts in five broad bands (u′,g′,r′,i′,z′) from imaging data taken during the commissioning phase of the Sloan
Digital Sky Survey (SDSS). The counts are derived from two independent stripes
of imaging scans along the Celestial Equator, one each toward the North and the
South Galactic cap, covering about 230 and 210 square degrees, respectively. A
careful study is made to verify the reliability of the photometric catalog. For
galaxies brighter than r∗=16, the catalog produced by automated software
is examined against eye inspection of all objects. Statistically meaningful
results on the galaxy counts are obtained in the magnitude range 12≤r∗≤21, using a sample of 900,000 galaxies. The counts from the two stripes
differ by about 30% at magnitudes brighter than r∗=15.5, consistent with a
local 2σ fluctuation due to large scale structure in the galaxy
distribution. The shape of the number counts-magnitude relation brighter than
r∗=16 is well characterized by N∝100.6m, the relation
expected for a homogeneous galaxy distribution in a ``Euclidean'' universe. In
the magnitude range 16<r∗<21, the galaxy counts from both stripes agree
very well, and follow the prediction of the no-evolution model, although the
data do not exclude a small amount of evolution. We use empirically determined
color transformations to derive the galaxy number counts in the B and
I814 bands. We compute the luminosity density of the universe at zero
redshift in the five SDSS bands and in the B band. We find LB=2.4±0.4×108L⊙hMpc−3, for a reasonably wide range of
parameters of the Schechter luminosity function in the B band.Comment: 48 pages, 15 figure