This image shows the region around Supernova 1987A as photographed in ultraviolet light on January 8, 1994. Prior to the installation of COSTAR on the HST, the ring around the supernova was not readily discerned in ultraviolet images, if seen at all. But in this image, details of the ring, including its wavy structure, are vividly apparent.
A faint star of about the 20th magnitude seems superimposed on the ring at the lower right. A well-known bright star (which was outside the image area reproduced in the preceding illustration) is partially shown at lower left. The 29th magnitude star has not been studied sufficiently to determine for sure where it is. It may be a rather bright ordinary star located in the Large Magellanic Cloud at approximately the same distance as the supernova. In that case, it appears faint because it is so far away. Alternatively, it may be a small, dim object - a white dwarf star - located much closer to Earth in our own Milky Way Galaxy.
Careful measurements of the debris from Supernova 1987A, which is the bright, image centered in the elliptical ring, show that the debris cloud has doubled in size since August 1990. As observed in January 1994, the cloud image had a diameter of one-quarter of a light year. Thinner, faster-moving gas on the outskirts of the debris cloud may actually have reached the ring by now. The main debris should strike the ring at some time around the year 2000, give or take a few years. When that happens, a strong burst of x-rays is likely to occur, and astronomers will use the HST to try to determine the effect of the collision on the ring.
Camera: Faint Object Camera with COSTAR
Credit: P. jakobsen (ESA/ESTEC), F. D.
Macchetto (STScl and ESA), R. Jedrzejewski (STScI), N Panagia (STScl and
ESA), NASA, and ESA
