  The top quark mass measurement with ATLAS in the lepton plus jets channel is
summarized from the perspective of the early data. Using the invariant mass of
the three jets arising from the hadronic side as the estimator of the top quark
mass, a precision of the order of 1 to 3.5 GeV on the top quark mass
measurement should be achievable, assuming a jet energy scale uncertainty of 1
to 5%.
