SN 1987A at radio wavelengths

SN1987A has an intrinsic radio luminosity some four orders of magnitude less than SN1993J at maximum, largely a reflection of the tenuous wind from the progenitor of SN1987A before explosion. Both remnants have an edge-brightened, ring-like morphology though, in the case of SN1987A, the expansion rate is currently only around 3500 km s(-1). The flux density of the remnant of SN1987A continues to rise at all measured radio frequencies. Its spectral index is gradually flattening, indicating its transition into the supernova remnant phase. A campaign to increase the resolution of radio imaging by observing at higher frequencies is underway with the Australia Telescope Compact Array (ATCA).