First results from the Faint Object Camera: SN 1987A

We present the first images of SN 1987A taken on day 1278 after outburst with the Faint Object Camera on board the Hubble Space Telescope. The supernova is well detected and resolved spatially in three broadband ultraviolet exposures spanning the 1500-3800 Å range and in a narrow-band image centered on the [O III] λ5007 line. Simple uniform disk fits to the profiles of SN 1987A yield an average angular diameter of θ ≃ 170 ± 30 mas, corresponding to an average expansion velocity of υ ≈ 6000 km s -1. The derived broadband ultraviolet fluxes, when corrected for interstellar absorption, indicate a blue ultraviolet spectrum corresponding to a color temperature near 13,000 K. The luminosity of SN 1987A in the ultraviolet, L ≃ 2 × 10 36 ergs s -1, is comparable to that emitted in the visible-through-infrared portion of the spectrum. Finally, the narrow-band [O III] image reveals that the circumstellar nebula known to surround SN 1987A has the shape of a thin, tilted ring having a radius 0.20 pc and a thickness ≃ 2 × 10 -2 pc.