In preparation for New Generation Space Telescope (NGST), members of the
supernova group have used different assumptions for the combination of dust
extinction and star formation up to redshifts 
, as well as
detailed modelling of supernova properties, to estimate the number of
supernovae that should be observable with this telescope. Realistic light
curves and spectral shapes that evolve with time for the different types
supernovae are used. It is found that NGST should be able to detect
several tens of core-collapse events in a single detection if the
observational limit in the range 
m is 1 nJy and the field is 16
square arcmin. The observable number of Type Ia supernovae is also
estimated. Due to the time delay between the formation of the progenitor
star and the explosion of the supernova, there are additional aspects that
have to be considered when interpreting observational rates of these
supernovae.