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The active galaxy Centaurus A and the X-ray binary systems Vela X-1, Centaurus X-3, and Circinus X-1 were monitored for VHE gamma-ray emission above 1 TeV with the JANZOS Cerenkov facility during 1988 and 1989. No evidence was found for persistent or episodic emission from any of these objects. Subsequent upper limits on the integral fluxes of 2.2×10 −11 , 2.8×10 −11 , 4.0×10 −11 ,and 4.2×10 −11 cm −1 s −1 , respectively, were obtained for these objects. These limits are consistent with results of observations made by other groups

The supernova SN 1987A has been observed with the JANZOS cosmic-ray facility at the Black Birch Range in New Zealand since October 1987. From May to July 1988, observations were carried out using the Cerenkov telescope at a zenith angle of 68 deg. By working at large zenith angles, the effective detection area and energy threshold are both increased. From 39 hr or greater of observation, an upper bound of 5.7 x 10 to the -14th/sq cm sec on the flux of gamma rays with energies of 75 TeV is obtained at the 95-percent confidence level. This flux limit corresponds to the gamma ray luminosity of 10 to the 37th ergs/sec. 20 refs.