1.5.3  Expected Performance

	From an apogee of 80 km, the NiteOwl instrument will scan the horizon, viewing stars as it falls through the mesosphere.  The instrument will image unocculted stars of magnitude 3.0 or brighter with a minimum signal to noise ratio of 100:1 while rotating at a rate of 6( per second.  The visual accuity will be 5 nm in the spectral domain and 1 min of arc in the spatial domain.

	It has been determined that zeniths are available over Churchill whose corresponding horizons contain no stellar gaps larger than 12% of the azimuthal range for third magnitude stars and brighter.  This is based on the star database supplied by the Finnish Meteorological Institute for the GOMOS project.

	Ozonesonde performance ???