Observations of the Small Magellanic Cloud with the Ultraviolet Sky Survey telescope

Absolute surface-brightness measurements of the Small Magellanic Cloud in three wavebands centred on 1550, 2350 and 2740 A have been obtained with the Sky Survey Telescope (S2/68) in the TD-1 satellite. The two colours (m1550-m2740) and (m1550-m2350) have been constructed for six regions in the Cloud. A comparison of the observed colours for a region in the wing with those predicted by the luminosity function for the same region suggests that there is a small amount of reddening in the wing and that the ultraviolet extinction law is similar to the galactic extinction law. The equivalent spectral type of main body of the Cloud becomes progressively earlier from the south to the north. The integrated magnitude of the SMC in each of the four wavebands centred on 1550, 1950, 2350 and 2740 A has been determined from low-resolution mapping of the Cloud. The integrated colours of the SMC correspond to those of a galactic main-sequence B9 star. (author)