Supernova 1987A was the explosive death throes of a blue supergiant star in the Large Magellanic Cloud, a satellite galaxy of the Milky Way. Following the supernova, the star that exploded was identified on earlier telescopic photographs. The supernova was discovered by lan Shelton at the Las Campanas Observatory, in Chile, on February 24, 1987. Initially visible to the naked eye, it was the brightest supernova since the year 1604.
This false-color Hubble image was taken on August 23, 1990, through a filter isolates light from doubly ionized oxygen atoms. The debris of the shattered is the pink blob at the center of the yellow elliptical ring. Comparison of the blob with images of stars taken with the same camera demonstrates that it is really extended, not pointlike, so that the expansion of the stellar debris into surrounding space has been directly imaged. Using HST images of Supernova 1987A and other data, it was possible to measure the distance to the Large Magellanic Cloud more accurately than ever before and it was found to be 169,000 light years away.
Theories abound as to the nature of the elliptical ring, but it is clear that it is too large to represent ejecta from the supernova so soon after the explosion. The ring must have surrounded the blue supergiant before it became a supernova. A flash of ultraviolet light from the exploding star probably excited the gas in the ring and made it glow. Some astrophysicists have concluded that the ring is actually the dense gaseous 'waist' of a thinner, hourglass-shaped formation produced by stellar winds that had blown off the star before it became a supernova.
Camera: Faint Object Camera (1990)
Technical Information: Image taken in
the light of doubly ionized oxygen at 501 nm.
Credit: NASA and ESA
