N6946-BH1 is a disappearing supergiant star and failed supernova candidate formerly seen in the galaxy NGC 6946, on the northern border of the constellation of Cygnus. The star, either a red supergiant or a yellow hypergiant, was 25 times the mass of the Sun, and was 20 million light years distant from Earth. In March through to May 2009 its bolometric luminosity increased to at least a million solar luminosities, but by 2015 it had disappeared from optical view. In the mid and near infrared an object is still visible; however, it is fading away with a brightness proportional to t−4/3. The brightening was insufficient to be a supernova; the process that created the outburst is still uncertain.