  Suggestions have been made that the microwave background observed by COBE and
WMAP and dubbed Cosmic Microwave Background (CMB) may have an origin within our
own Galaxy or Earth. To consider the signal that may be correlated with Earth,
a correlate-by-eye exercise was attempted by overlaying the CMB map from
Wilkinson Microwave Anisotropy Probe on a topographical map of Earth.
Remarkably, several hot spots in the CMB map are found to be well aligned with
either large cities on Earth or regions of high altitude. To further study the
correlations between Earth and CMB, we performed a complicated
cross-correlation analysis in the multipole space. The overall correlations are
detected at more than 5 sigma confidence level. These results can be naively
interpreted to suggest that large angular scale fluctuations in CMB are
generated on Earth by a process that traces the altitude relative to a mean
radius. Simply extending our analysis, we suggest that cross-correlations
between CMB and any other map of a Solar system body, image of a person, or an
image of an animal will be detected at some statistical significance. It is
unclear how Occam's razor can be applied in such a situation to identify which
sources are responsible for CMB fluctuations.

Astrophysics