V404 Cyg is in outburst on the POSS2/UKSTU Blue image in the VSX! Is it possible to track down the date this image has been taken? The last known outburst was in 1989.
I cannot get the POSS/UKTSU image via VSX, but downloaded here:
I don't see V404 Cyg being too bright, estimated about 16.4B.
The date of the image: 30.36 June, 1989.
It is definitely in outburst, much brighter than in quiescence. It was already fading. Full outburst was in May 1989.
Thanks for finding this out!