A last weakly visible brightness maximum of approximately 5.5 to 6 magnitude was observed by Hevelius in March 1672 and finally faded from view late May.

That object and another star are thought to be seen though dense nebulosity associated with CK Vulpeculae which causes them to vary dramatically in brightness.

[10] CK Vulpeculae now consists of a compact central object with gas flowing out at approximately 210 km/s into a bipolar nebula.

[4] Known ionic emission lines in the spectrum, and unidentified absorption features in the infrared indicate a temperature between 14,000 K and 100,000 K.[3] Astronomers using the Atacama Large Millimetre Array (ALMA) and the Northern Extended Millimeter Array (NOEMA) radio telescopes to study CK Vulpeculae have found the first convincing evidence of a radioactive molecule outside the Earth's Solar System, which is aluminium monofluoride as the 26Al isotopologue.

[15] Although it was previously considered to be located about 2,280 ly (700 pc) away,[10] a 2020 paper ruled this out due to a larger distance for CK Vulpeculae making the intrinsic energy release too great for a stellar merger.

Instead the 2020 paper concludes that the CK Vulpeculae outburst was an intermediate luminosity optical transient with an unknown cause.