The Wilkinson Microwave Anisotropy Probe, launched on 30 June 2001, has
released the data from its first year of observation at the Earth-Sun
L2 Lagrange point.  All-sky maps in five bands from 22 to 94 GHz give
high signal to noise ratio detections of the cosmic microwave
background anisotropy and the galactic foregrounds for angular scales
between 0.2 and 180 degrees.  The correlation between polarization and
temperature anisotropies due to electron scattering in the surface of
last scattering is seen at small angles, and a large angle correlation
due to electron scattering after reionization in the Universe at a
redshift of about 20 is also seen.  The angular power spectrum of the
anisotropy agrees well with the predictions of a flat, vacuum-dominated
Lambda-CDM model.