NGC 2033 = LMC-N154B = ESO 056-157 = S-L 589 = LH 81

05 34 30 -69 46 48; Dor
Size 10′

14″ (4/4/16 – Coonabarabran, 145x and 230x): large bright star cloud (stellar association LH 81), ~10′ diameter with ~50 stars (depending on size taken) mag 11-14.

Adding an NPB filter brings out the associated nebulosity (N54), which is fairly bright and very large. A curving swath of nebulosity, elongated E-W for ~8′ is on the SW side of the association. The cluster itself is also encased in diffuse nebulosity with the filter. NGC 2037 is generally taken as a small knot (BCDSP 8) within this star cloud. NGC 2048, a bright emission nebula, is at the NE end of the association and together with NGC 2033 form part of a Superbubble.

Notes: James Dunlop discovered the NGC 2033/2037 = D 141 on 24 Sep 1826. He described “a faint nebula about 4′ long, very faint at the extremities, brightest and broadest in the middle. This (position) is in the north following side of an extended cluster of very minute stars, rich in number.” Although his reduced position was ~11′ too far SE, his handwritten drift notes recorded it 5 minutes of time after NGC 2005 and 5′ N, landing within the NE side (as described) of the LH 81 association.

John Herschel rediscovered NGC 2033 between Nov 1836 and Mar 1837 with a 5-inch refractor and recorded it as #579 in his preliminary catalogue of “Stars, Nebulae and Clusters in the Nubecula Major.” Herschel’s position falls in the large stellar association LH 81. But as there is no listing or description in his CGH catalogue, it’s possible Herschel was recording a small knot or a very large field of stars + nebulosity. So, the size and center is unknown. See NGC 2037 for more. The large nebulosity on the south side of the association might be NGC 2052. See that number.

NGC 2048 = ESO 056-166 = LMC-N154A = LH 87

05 35 56 -69 38 54; Dor
V = 12.2; Size 2′

14″ (4/4/16 – Coonabarabran, 145x + NPB filter): NGC 2048 is a bright elongated glow, ~1’x0.7′ E-W, surrounded by fainter nebulous haze extending 3′-4′ in diameter. The emission component (N154A) is cradled around the S and E side by a large, semicircular chain with mostly mag 12 stars and a total length of ~15′ (association LH 87). At the W end of this chain is HD 37836, a mag 10.6 emission-line B0 supergiant (LBV candidate).

NGC 2048 is situated in a glorious region of the LMC; extending to the SW is NGC 2033 = LH 81, a large stellar association (the stars on the S side of the semicircular chain are likely members) and further N is NGC 2055 = LH 96, a huge rich cloud just S of the Tarantula Nebula.

Notes: John Herschel discovered NGC 2048 = h2926 in 1834-1835 (exact sweep or date unknown as based on a sketch of the Tarantula Nebula (NGC 2070) region made over several nights in Nov 1834 and Dec 1835). He described “a very faint large oval ill-defined nebula; not taken in sweeping, but laid down from a careful drawing. See Notes on Catalogue of Nubecula Major”. His position is 3′ NE of the center of this nebula. Hodge and Wright describe it as “possibly only 2-3 stars in nebulosity” in their LMC Atlas.