This planetary nebula is located 11000 light years away in the constellation of Orion at a declination of +12 degrees. It is a magnitude 15.2 PN which spans 40 arc-seconds in our apparent view. This corresponds to a span of 2 light years. The PN is believed to well evolved, at an age of 20,000 years.
Although OIII signal is present, the HII signal is dominant here. An excellent 2015 paper, “
Deciphering the bipolar planetary nebula Abell 14 with 3D ionization”, concluded that this is a bipolar nebula and we are seeing the torus (thick ring) section from a view which is just off of side-on. This PN did not make sense to me until I saw it as a ring from that perspective, like looking at a short cylinder from the side.
The bright blue giant star at the center of the PN is obvious. The above paper concluded that such a star is not hot enough to ionize the surrounding gas. Therefore, it is likely that a hotter unseen companion star is the progenitor.
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