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Images recorded with MegaCam are used to investigate the recent star-forminghistory (SFH) of the Local Group Sc galaxy M33. The properties of the stellardisk change near R = 8 kpc. Within this radius the star formation rate (SFR)has been constant with time during at least the past 250 Myr, while at largerradii the SFR has declined during this same time period. That the recent SFR inthe inner disk has been constant suggests that M33 has evolved in isolation forat least the past ~ 0.5 Gyr, thereby providing a constraint on the timing ofany recent interaction with M31. The fractional contribution that young starsmake to the total mass of the stellar disk changes with radius, peaking near 8kpc. Evidence is also presented that the SFR during the past 100 Myr in thesouthern half of the galaxy has been ~ 0.4 dex higher than in the northernhalf. Finally, structures with sizes spanning many kpc that contain blueobjects - presumably main sequence stars that formed during intermediate epochs- are identified near the disk boundary. It is argued that these are tidalfeatures that were pulled from the main body of M33 and - in some cases - arethe fossil remnants of star formation that occured in an extended disk duringintermediate epochs.

The Stellar Archeology of the M33 Disk: Recent Star-Forming History and Constraints on the Timing of an Interaction with M31