In the absence of knowing that the close neighbours N103 and N105 are both superbubbles, one would never know for their shells are undetectable to our telescopes. They are striking, both individually and as a “pair”, for their dazzling inhabitants dominate the scene with their brilliance. N103 is dominated by the dazzlingly bright young globular cluster NGC 1850, while N105’s dazzle is provided by the blaze of NGC 1858’s stars and nebulosity, as well as the gorgeously bright young globular cluster NGC 1855. And being bar inhabitants, all this dazzle is set against a backdrop packed with stars twinkling against the bar’s incredible pearly-silver shimmer… not to mention a lot of clusters in the close neighbourhood! It is an unutterably gorgeous scene.

The superb “pair” of superbubbles; N103 upper right; N105, lower left.

The huge, extremely bright NGC 1850 overwhelms N103’s superbubble scene. Not only is NGC 1850 the brightest star cluster in the Large Magellanic Cloud, but it also has a tiny companion cluster, NGC 1850A, lying 30″ W of centre. Both are very young, NGC 1850 is 40-50 million years old and the smaller cluster, composed of extremely hot, blue stars and fainter red T-Tauri stars, is a mere 4 million years old.

Stunning NGC 1850 with its small companion, lower right, and the superbubble’s filamentary nebulosity on the left. Credit: ESA, NASA and Martino Romaniello (European Southern Observatory, Germany)

16″ at 228x: It never fails to astound me what one can see with a pair of 10×50 binoculars and NGC 1850 is visible as a small, bright glow in the bar’s large shimmering glow. At the scope, it is a most magnificent globular! It is huge, ~4′ in diameter, with an extremely bright, irregular, dazzling core, ~1′ in diameter. Scores of resolved mag 13.5 and fainter stars appear to burst out of the brilliant core, many in haphazard chains, (except oddly, on the south-southeast side); the stars set against the lovely glow of unresolved stars that grows fainter to the edge of the cluster’s vast halo. Frankly, this would be a stunning globular cluster if it were floating over there in our own galaxy’s sky… never mind a galaxy whose sky is 163,000 light-years away! NGC 1850A appears as a tiny clump of brightness just off the western side of the core.

The cluster SL 260 lies to the north of NGC 1850, and appears as a fairly faint glow of unresolved stars, irregular, ~15″ in diameter.

In its Hubble images, the nebulosity bears a marked resemblance to our own Milky Way’s supernova remnant, the Cygnus Loop, but alas, the UHC filter didn’t reveal any of it. However, small, faint SNR N103B, lying on the outskirts of the superbubble, has a good response to the filter, appearing as a faint, round nebulous glow with edges that fade rapidly into the surrounding glow of the bar.

16″ at 228x + OIII filter: Small, faint SNR J0508-6843, lying on the outskirts of the superbubble, appears (without a filter) as an extremely faint and amorphous, barely-there glow, but it has a good response to the OIII filter, appearing as a faint, round nebulous glow, ~20″ in diameter, with edges that simply fade away into the surrounding glow of the bar.