AST-0228813<br/>Reich, Robert<br/><br/>The sensitivity of the three-telescope IOTA, a Michelson Stellar Interferometer will be improved through the addition of a new high speed visible light tip/tilt tracker, single-mode IR fiber optics, and an improved IR tip/tilt tracker, which will be used to observe highly reddened object that are untrackable with the visible sensor. These improvements will extend the limiting astronomical magnitude for science measurements from the current 7.5 magnitude limit (R-band) to a 9.0 magnitude limit (R-band). This new system will enable studies of surface features and mass exchange interactions across the surface of the photospheres of Herbig Ae/Be stars and T Tauri stars. . <br/>***