HiTIES: A High Throughput Imaging Echelle Spectrogragh for ground‐based visible airglow and auroral studies

We describe an imaging spectrograph with high spectral resolution (0.3 A) that uses an echelle grating without the conventional cross disperser. The spectrograph covers the entire visible region. However, only 5 – 20 wavelength regions can be observed simultaneously. The total wavelength coverage is limited by the number of available pixels on the detector and for a 1024 × 1024 pixels detector is ∼ 100 – 300 A. Order separation is achieved by a mosaic of interference filters located at the image plane.