Were there any images of Sanduleak -69 202 (progenitor of SN1987A) before it exploded? We all know about SN1987A, the closest observed supernova since Kepler's time. Its progenitor was Sanduleak -69 202, a magnitude 12 blue supergiant, catalogued in 1970. Were there any images of this star before it exploded, and how did we know that this was the star that produced said supernova?
Yes, it is clearly visible in photographs of the LMC from the 1980s.  It is shown in this comparison from the Australian Astronomical Observatory
We know it was this star in the most simple possible way: The supernova occurred exactly at the same location as this star, and when we look now, that star has gone (replaced by a little bipolar supernova remnant)