  The Cosmic Microwave Background provides our most ancient image of the
Universe and our best tool for studying its early evolution. Theories of high
energy physics predict the formation of various types of topological defects in
the very early universe, including cosmic texture which would generate hot and
cold spots in the Cosmic Microwave Background. We show through a Bayesian
statistical analysis that the most prominent, 5 degree radius cold spot
observed in all-sky images, which is otherwise hard to explain, is compatible
with having being caused by a texture. From this model, we constrain the
fundamental symmetry breaking energy scale to be phi_0 ~ 8.7 x 10^(15) GeV. If
confirmed, this detection of a cosmic defect will probe physics at energies
exceeding any conceivable terrestrial experiment.
