Object Note
Nov 2, 2020    

It is likely William Hershel only saw the bright knot in the western reach at 02h25'26.97" +62°00'35.8". The entire nebula complex is Sharpless 2-190, the Heart Nebula, encompassing well over a degree in RA and two degrees in declination.

There are multiple associated catalog numbers encompassing this nebula complex as ever better observations and photography revealed fainter structure. NGC 896 being the bright knot in the northwest reach. IC 1805, the embedded star cluster at the center was first described by E. E. Barnard in the late 1890's. There is also IC 1795, a bright area of emission to the northwestern end of the complex also described by Barnard, and IC 1831, a faint streamer of emission to the northeast discovered by Max Wolfe in 1906.

Harold Corwin

Though William Herschel noted the polar distance as uncertain, his position is only 4 arcmin south of the nebula, a bright knot in a huge HII ring (or possibly a supernova remnant). In addition, Caroline Herschel has reduced a position with respect to another star in the sweep (HD 24480) that is almost identical with that derived from the offsets published in William Herschel's PT paper (the second catalogue of nebulae and clusters).

Wolfgang suggests that this is identical to IC 1795 (which see), found by Barnard. I think that is unlikely as Barnard's position is close to another knot in the same nebula. Unfortunately, Barnard's observation is apparently one that he communicated directly to Dreyer, so we cannot easily check its details. Until we can see that observation, I am going to assume that Barnard (and Dreyer) knew about the proximity of the two objects and thought they were different enough to warrant two numbers.

― NGC Notes by Harold Corwin

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