Our present OOTW starts as often with a funny and exiting history. William Herschel discovered this object in November, 1790 as a "star with atmosphere". With this discovery he changed his theory about planetary nebula. He was thinking partly right, that the nebula mass were not unresolved stars but "luminous fluid" around the dominant central star which is a product of the nebula mass itself. Remember, Herschel uses a 18.7-inch speculum mirror, which is comparable with a modern 10-inch to 12-inch reflector. With bigger mirrors, details began to be resolved. Also at NGC 1514. Lord Rosse and his co-observer saw the first details in the halo and interpret, sketch and classify them as spiral structure ("new spiral of an annular form round the star, which is central; spirality is very faint"). The used "Leviathan" telescope has a 15-times larger light gathering power and uses a 72-inch speculum mirror, comparable with a modern 36-inch reflector.
But what is NGC 1514 or better, why does it looks like a Crystal Ball. What do we see - an inner shell, some bubble structures and an outer shell, often called halo here around a single bright central star. Today we know, that the central star - a binary system causes the morphology of nearly all non-spherical PNe. The 9.4mag bright BD +30°623 central star consist of a cool main component and a hot companion with a record breaking period of over 9 years [2017A&A...600L...9J]. The observed structure is only a two dimensional projection of a complicated structure. By using high resolution long-slit spectra, the latest scientific studies shows a 3D model of the PN [link to the preprint arXiv:2105.01495]. This model presents an inner distorted shell with some additional and well-defined bubbles and an outer spherical attached shell. The pictured model is very clearly and I recommend to view this at side 7.
From the observing side, NGC 1514 is one of the only PNe who shows his central star even in binoculars. To resolve the single bubbles needs some patience, but is possible to see even in smaller apertures. My former 16-inch shows clear sights of these structures. Because of its strong [OIII] emissions, a filter might help to resolve the morphology. To show all its natural beauty I often go without any filter. The shell structure is also visible. More important is the use of the right magnification and EP - high enough to resolve the structure and small enough to pass enough light. 1.5-2.0mm should work fine.
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