Spatial interferometry in the mid-infrared region

The potential of high-resolution spatial interferometry for detailed mapping and precision astrometry in the mid-infrared region, somewhat analogous to interferometry now done in the microwave region, is discussed from an instrumental point of view. Some results from a prototype system and from tests of atmospheric properties are given. The design of a more advanced two-telescope system now under construction is outlined. This involves movable telescopes of 1.65 m aperture and of high precision, using heterodyne detection of infrared in the 10 Μm atmospheric window.