In 1963 whilst examining the POSS plates Kohoutek came across a number of new nebulae, most of which he was able to identify as planetary nebulae.
These were published in the bulletin of the Czech Astronomical Institute Circular in 1963 as BAICz14. However, in the case of some of the objects he
discovered he was not able to confirm their type. These were listed in his table 2. The object we are interested in here is the first in this list of
questionable objects, K 2-1. Over the years this object has been variously catalogued as an irregular galaxy (UGCA 100), a bright nebula (LBN 809) or
even a reflection nebula (DG 50). SIMBAD classifies this object as a diffuse nebula with notes saying it is not a galaxy or a planetary nebula. This is
somewhat odd as the current professional planetary nebula (HASH) database classifies it as a true planetary nebula. Unfortunately, there have been
no professional studies of this object. In the discovery paper Kohoutek remarks on a blue star near the centre of the nebula at about 18th mag which
could be the central star. Lying in Auriga K 2-1 (PN G173.7-05.8 is thus a somewhat an unusual object. Although it has been imaged for some time there
are not many visual observations of this object. It was popular to observe in the early 90’s but seems to have dropped out of favour since then.
(see Webb QJ 100 for an article on the visual observations up to then). The fact that most of those reports suggest that it responds well to an OIII
filter does suggest that this object is indeed a planetary nebula. It may not be that faint as Kent Wallace reported it was visible in his 8” but I think this
observation maybe an outlier as it is probable that a 12” (30cm) telescope with an OIII filter may be required to see it from good skies. My observations
of it with a 20” show it as an irregular patch which stands out well with an OIII filter. Use of the Wayback Internet archive to try and extract observations
from the long gone, but much lamented, planetary nebula site blackskies.org suggests there is only one observation in its database which I suspect is the
original one from Jack Marling with his 17.5”. There is also a putative cluster here (Skiff J0507+30.8) but it is suggested now that this may merely be an
absorption hole and not a true cluster.
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