1998). The most prominent are the original spot at position angle $29^{\circ}$ and a group of spots just south of east between position angles of $90^{\circ}$ and $140^{\circ}$.

At radio wavelengths, the initial outburst was very short-lived (Turtle et al. 1987) compared to other radio supernovae (e.g. Weiler et al. 1998). This prompt outburst is attributed to shock acceleration of synchrotron-emitting electrons in the stellar wind close to the star at the time of the explosion (Storey & Manchester 1987; Chevalier & Fransson 1987). After about three years, in mid-1990, radio emission was again detected from the supernova, with the Molonglo Observatory Synthesis Telescope (MOST) at 843 MHz (Ball et al. 1995) and with the Australia Telescope Compact Array (ATCA) at 1.4, 2.4, 4.8 and 8.6 GHz (Staveley-Smith et al. 1992; Gaensler et al. 1997). This emission has increased more-or-less monotonically since its first detection. The spectral index over the observed frequency range has remained close to $-0.9$, indicating optically thin synchrotron emission. X-ray emission was observed to turn on at about the same time as the second phase of radio emission and also has increased in intensity since then (Gorenstein, Hughes & Tucker 1994; Hasinger, Aschenbach & Trümper 1996). 