This object is a very faint planetary nebula 1000 light years away. It is the most northern
Sharpless object and is located in the constellation of Cepheus at a declination of +81 degrees.
Nicknamed the Valentine Rose Nebula, the reddish Ha region of the nebula appears in the shape of a horseshoe, while the cyan OIII region towards the bottom right has a multiple arc front structure.
The white dwarf proginator star has moved away from the center of the nebula. It is the crisp bluish star towards the center of the OIII area, best seen in the full resolution view.
There has been lengthy ongoing debate over the years about whether or not this object is a planetary nebula. It was first classified as an HII region. It was then re-classified as a planetary nebula after the white dwarf was identified. In 2010, scientific work concluded that it was not a planetary nebula but a Strömgren sphere, i.e. unrelated interstellar medium excited by the moving white dwarf. However, radio results in 2015 are inconsistent with a Strömgren interpretation for Sh 2-174, so the latest thought is that it is a planetary nebula. If it is a planetary nebula, it is one of the few that does not have a circular shape, likely due to interaction with the
ISM. In any case, it is a beautiful, although very dim, deep sky object.
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