Possible closest planetary nebula surrounding the hot subdwarf BD+28 4211

The possible nearest planetary nebula, at a distance of about 112 pc, was detected in DR0.2 of the Northern Sky Narrowband Survey. The likely progenitor BD+28 4211 lies almost exactly in the center of a 5°-large OIII region. Together with a faint [SII] and H-alpha glow in the outer region, the apparent diameter of this nebula is about 6°, and the real diameter is about 12 pc. This resource is a permanent snapshot of the webpage Possible closest planetary nebula surrounding the hot subdwarf BD+28 4211, including all (interactive) media. It is intended for citation purposes, when referencing a volatile webpage is not appropriate. In order to use it, download the .zip archive, unpack it and load the file peg-cyg/index.html in a web browser. Except for a few external links, this copy can be used independently (or offline).