Ground based instrument for observing near IR nightglow inhomogeneities at zenith and throughout the sky.

An instrument for the study of the dynamics of the upper terrestrial atmosphere by optical method has been built. It is an automatic high sensitivity imaging system able to record the spatial variation of the nightglow intensity in the near IR. The low intensity and contrast of the structures led to a system combining a TV imager and a photo camera. This instrument will be routinely operated at Dumont d'Urville (Antarctica). We present below the pictures of spatial structures of the OH radical emission observed at zenith. The emission originates from a region 85 km above the surface. These pictures were obtained at the Observatoire de Haute-Provence (France) for the verification of the instrument performances.