The Chandra Legacy 1 Megasecond Observation of NGC 3115
We present initial results from the Chandra 1 Megasecond observation of the nearby S0 galaxy NGC3115, which harbors the nearest >1e9 solar mass supermassive black hole. The goal of this legacy-type project is to put the first direct observational constraints on the temperature and density structure of an accretion flow inside the Bondi radius of a supermassive black hole. These temperature/density constraints will provide a critical test for competing inefficient accretion flow theories. The large angular Bondi radius of NGC3115's black hole provides the *only* opportunity to perform such a test of inefficient accretion flow theory in the Chandra era and the foreseeable future. In addition to providing temperature and density profiles of the hot gas, this long observation also represents the deepest look at the X-ray binary population of a normal early-type galaxy.