  The ``moving puncture'' technique has led to dramatic advancements in the
numerical simulations of binary black holes. Hannam et.al. have recently
demonstrated that, for suitable gauge conditions commonly employed in moving
puncture simulations, the evolution of a single black hole leads to a
well-known time-independent, maximal slicing of Schwarzschild. They construct
the corresponding solution in isotropic coordinates numerically and demonstrate
its usefulness, for example for testing and calibrating numerical codes that
employ moving puncture techniques. In this Brief Report we point out that this
solution can also be constructed analytically, making it even more useful as a
test case for numerical codes.
