LMC 2 Supergiant Shell
The Large Magellanic Cloud’s most spectacular supergiant shell

Image credit & copyright: Team Ciel Austral
RA: 05h 00m Dec: -65° 40′
Diameter: 2,900 light-years
OB Associations: LH 101, 103, 104, 105, 106, 108, 111
NGC Objects: NGC 2091, 2092, 2093, 2100, 2102, 2108, 2113

Supergiant Shell LMC 2
Not only is LMC 2 the Large Magellanic Cloud’s most spectacular supergiant shell (SGS), but its location is also the most spectacular as it lies to the southeast of the ferocious starburst region 30 Doradus with its fabulous Tarantula Nebula, SNR and superbubble. It was one of the first supergiant shells to be identified in the LMC by Goudis & Meaburn (1978), based on the detection of long, curved Hα filaments extending over an astounding 900 pc (~3,000 light-years). And indeed, it has the brightest, most coherent filamentary structure of all known SGSs in the Cloud.
An absolutely massive ridge of active star formation regions stretches down its western edge (including N158, N159, and N160) and long filaments lie to the east.
Four OB associations, LH 101, 103, 104, 105, ionize the H II regions along the western edge. A fifth, LH 108 lies just to the east of LH 103 and 105. (All five are incorporated in the gigantic star cloud LH 106.) Only one OB association, LH 111, lies in the interior. It is slightly older than the OB associations along the western edge and is not associated with any H II region.
Low magnification overview
A low magnification overview of this magnificent supergiant shell gives one an idea of its sheer size and power. Without a filter, the colossal shell is swamped by stars along its western side where the enormous star cloud, LH 106, overlays the bright and complex nebulosity of the ridge of active star formation. The individual OB associations (LH 103, 104, 104 and 108) stand out boldly within the ocean of stars that are strewn across the glowing nebulosity. The two superbubbles, N158 and N160, and the ferocious star-forming complex, N159, dominate the scene. In the interior of the shell, one’s eye is drawn to the bright glow of the gorgeous young globular cluster NGC 2100 which lies on the eastern side of LH 111. Other small glows and gleams lie around haphazardly calling out for increasing magnification.
Adding the UHC filter is astonishing! The two superbubbles and the turbulent cauldron of star birth are staggeringly big, bold, and bright. The nuances and depths of the nebulosity is astonishing for low magnification. The other nebulosity is also impressive: N163 appears as a large, round, faint glow; N164 appears as a fainter, but also big and round glow; N169A appears as a small, bright, round glow. And very faint washes of nebulosity lying around here and there look like wispy wafts of smoke the moment before it dissolves into a windy sky.
A celestial geode superbubble

N158 Superbubble
A celestial geode superbubble

N158 Superbubble
A star-forming maelstrom

N159 Star-Forming Complex
A star-forming maelstrom

N159 Star-Forming Complex
The superbubble with ghostly eyes

N160 Superbubble
The superbubble with ghostly eyes

N160 Superbubble
A colossal star cloud

LH 106
A colossal star cloud

LH 106
H88 308 (Open Cluster)
RA 05 40 49.0 Dec -69 22 48 Mag 11.7 Size 0.8′
16″ at 228x: The cluster lies outside the NE edge of superbubble N158’s rim, and appears as a fairly bright oval, ~18″ in diameter, oriented SSE-NNW. It is smooth and even, and no stars are resolved.

H88 308
NGC 2091 (Open Cluster)
RA 05 40 57.7 Dec -69 26 11 Mag 12.0 Size 1.0′
16″ at 228x: Small NGC 2091 lies to the east of the bright strand of nebulosity that sweeps eastwards along superbubble N158’s eastern rim, looking as if a scrap of stellar stuff was flung aside. It appears as a fairly bright 35″ x 20″ oval glow of unresolved stars, oriented E-W. It has nicely defined edges and only one faint mag 15 star is resolved, almost dead centre.

NGC 2091
N172 (H II Region)
RA 05 40 12.3 Dec -69 55 01 Mag – Size 0.8ʹ
16″ at 228x + UHC filter: This H II region appears as an exceedingly small, very faint smidgeon of dim light with no definite edges – they simply dissolves into the surrounding sky.

N172
N161 (H II Region)
RA 05 40 13.5 Dec -68 59 26 Mag – Size 0.9ʹ
16″ at 228x + UHC filter: Lying just off the NW shores of the Tarantula Nebula, N161 appears as a faint smudge of nebulosity, 20″ in diameter, oriented E-W. It has soft edges that simply melt away into the sky.

N161
KMHK 1231 (Open Cluster)
RA 05 41 10.7 Dec -69 54 12 Mag – Size 1.3ʹ x 1.1ʹ
16″ at 228x: KMHK 1231 appears pretty faint, irregular, ~20″ in diameter. No stars are resolved. Another cluster, very small BSDL 2800, lies on its southwest end, but I found it impossible to distinguish it from KMHK 1231. N177, the low excitation blob lies 1.5′ S.

KMHK 1231 (top)
N177 (Low Excitation Blob)
RA 05 41 34.5 Dec -70 01 19 Mag – Size 2.2ʹ x 1.5ʹ
16″ at 228x + UHC filter: This LEB appears as a very faint, amorphous smudge of pale light, ~20″ in diameter, whose edges simply dissolve away, adding to its formelss shape. But it is a blob, and any sighting of a blob is a great sighting!

N177 (bottom)
NGC 2092 (Open Cluster)
RA 05 41 22.0 Dec -69 13 27 Mag 12.2 Size 1.2′
16″ at 228x: Located just 4′ W of NGC 2100, NGC 2092 is overshadowed by its gorgeous neighbour! It appears very faint, ~40″ in diameter, round and hazy with a slight brightening to the centre. No stars resolved.

NGC 2092
HS 390 (Open Cluster)
RA 05 41 30.0 Dec -69 11 06 Mag – Size 0.6′
16″ at 228x: This extremely small, very faint, irregular droplet of light lies just beyond the NW end of the LH association LH 111, which was a handy way to located the little chap. The superb cluster NGC 2100 lies LH 111’s SE side.

HS 390
LH 109 = NGC 2093 (OB Association)
RA 05 41 50.9 Dec -68 54 57 Size 1.5ʹ x 1.3ʹ
16″ at 228x: This association is relatively young, just a few tens of millions of years. Astronomers say that it appears that its stars have already excavated a sizeable cavity around them that is now relatively void of gas. It appears as a fairly bright, and beautifully gritty glow, roundish, ~1.5′ in diameter. Six mag 14-15 stars are resolved across the cluster and a mag 11.7 star lies at the west edge. Mag 9.4 star (HD 38654) lies 3′ NW.

NGC 2093
LH 111 + NGC 2100 (OB Association + Young Globular Cluster)
RA 05 42 07.2 Dec -69 12 27 Mag 9.6 Size 2.5ʹ Age ~15 million
16″ at 228x: To my eye NGC 2100 is one of the loveliest young globular clusters in the Cloud! It’s beautifully bright, ~2′ diameter, with a bright and clumpy centre and spangled with the glittering points of around a dozen mag 12 and fainter stars. Furthermore, it is located at the eastern side of 6′ x 5′ LH 111’s rich cloudlet of stars. The association’s dozen or so mag 13+ stars lie swathed in a rich glow of unresolved stars with its brightest resolved stars appearing to stream out of the globular cluster in two parallel NNW-SSE strings. Lovely!!
Very interestingly, astronomers suggest that because of the age of NGC 2100, it is likely that all of its O-type stars have exploded as supernovae. Thus, NGC 2100 may have played an important role in the formation of LMC 2.

NGC 2100
NGC 2102 (Open Cluster)
RA 05 42 25.1 Dec -69 29 29 Mag 11.4 Size 0.9′
16″ at 228x: NGC 2102 lies just 17′ E east of the gorgeous superbubble N158, where the stars of the enormous star cloud, LH 96, peter out. The cluster appears as a bright knot, ~20″ in diameter. Four mag 14-15 stars are resolved against the glow of unresolved stars, including a mag 12.9 star at the south edge.

NGC 2102
LH 113 + N164 (OB Association + Emission Object)
RA 05 42 42.0 Dec -69 03 42 Mag – Size 2.0ʹ x 1.5ʹ
16″ at 228x: Mag 12.3 blue supergiant SK -69 287 (N164’s ionising star) lies prominently just north of the association’s centre, and it is accompanied by 3 small, faint stars and the cluster, HS 397A, lying to its northeast. The cluster appears as a small, round, faint glow of unresolved stars. They are all buried in the NNW-SSE oval glow of LH 113’s unresolved stars, and surrounded by a faint, small, haze of nebulosity. But what an incredible response to the UHC filter! N164 appears as a bright, NNE-SSW oval haze of nebulosity, ~2.5′ x 1.5′ in diameter. It is subtly uneven with edges that fade rapidly into the surrounding sky. Lovely!

LH 113 + N164
N163 (Emission Object)
RA 05 43 04.6 Dec -69 45 57 Mag – Size 6ʹ
16″ at 228x + UHC filter: N163 appears as a fairly bright, ~1.6′ irregularly round, uneven glow whose edges fade rapidly into the surrounding sky. A small, brighter arc of nebulosity lies on the SE end, open towards the NW. Without the filter, the cluster HS 400 lying on the northern side of the nebula, appears as 4 stars involved with the nebulosity, three of them in a NNW-SSE row, the fourth a mag 13 star on the north side.

N163
N165 (Supernova Remnant)
RA 05 43 08.0 Dec -68 58 18 Size 3.8′ Age 10,800 ± 7,300 years
16″ at 228x + OIII filter. N164’s bright and obvious patch of nebulosity to the south of N165, serves as a stepping-stone to the SNR but even so, I could see nothing of the SNR J0543-6900, bar a small H II region that lies on the north-western rim of the SNR, and of it, all I could see was a very faint glow, with a slightly brighter strand of nebulosity that forms the tiniest portion of its southern periphery. Unfiltered, it contains the mag 12.7 OB-star, Sk -68 155 – the only bright object to be seen!

N165
H88 327 (Open Cluster)
RA 05 43 40.5 Dec -69 15 57 Mag – Size 0.8′
16″ at 228xx: Lying south of a small N-S arc of gritty stardust with mag 11.3 HD 270046 at its NW end, this cluster appears faint and exceedingly small, just more than stellar.

H88 327
H88 329 (Open Cluster)
RA 05 43 45.1 Dec -69 13 34 Mag – Size 0.6′
16″ at 228x: This cluster, like H88 327 above, appears faint and exceedingly small, just more than stellar and lies north of the same small N-S arc of gritty stardust that lies north of H88 327.

H88 329
SL 683 (Open Cluster)
RA 05 43 48.8 Dec -69 47 18 Mag 12.6 Size 1.1′
16″ at 228x: SL 683 lies 3.6′ SE of the fairly bright round glow of the nebula N163. The cluster appears bright, compact, ~15″ in diameter, and round with crisp little edges. No stars resolved.

SL 683
NGC 2108 (Young Globular Cluster)
RA 05 43 56.3 Dec -69 10 54 Mag 12.3 Size 1.8′ Age < 3 billion years
16″ at 228x: A young globular cluster is always a delight and this one, albeit outshone by its gorgeous young globular neighbour NGC 2100 a mere 10′ WSW, is still a delight! It appears fairly faint, round, ~50″ in diameter, very slightly brighter to the centre and with no stars resolved.

NGC 2108
N166 (Emission Nebula)
RA 05 44 23.0 Dec -69 24 54 Mag – Size –
16″ at 228x + UHC filter: Luckily, N166 lies due south of the faint but noticeable N167, otherwise it would be tough to pick it up. With averted vision, it appears as a very, very small, round glow so faint that it is just barely visible; a mere droplet of dim nebulosity.

N166
N167 (H II Region)
RA 05 44 24.2 Dec -69 22 43 Mag – Size 1.7′
16″ at 228x + UHC Filter: N167 appears as an oval-shaped brighter patch, ~25″ in length, elongated NW-SE, with a very faint and very uneven, roundish patch extending to the north. The oval has fairly well defined edges, but the rest of the nebulosity displays no edges at all, it just dissolves into the sky.

N167
N168 = NGC 2113 (Cluster + H II Region)
RA 05 45 22.2 Dec -69 46 21 Mag – Size 1.7ʹ x 1.5 ʹ
16″ at 228x: Without a filter, this H II region is beautifully visible as a soft, round, ~45″ glow that extends westwards in a circular shape from N168A, a small, bright, elongated knot on the east side. There is a similar, but smaller and less bright elongated knot on the WSW side. The nebula has an excellent response to the UHC filter, with the glow increasing to ~1′ and revealing a faint hazy glow to the west. N168A is a fascinating object to observe for it is a young stellar object and let’s face it, it’s not every night one sees a star in the first phase of its life. Without the filter two very faint stars are resolved in the nebulous glow.

NGC 2113
HS 412 (Open Cluster)
RA 05 45 56.0 Dec -69 16 18 Mag – Size 0.8′ x 0.6′
16″ at 228x: This cluster appears fairly bright and very small; quasi-stellar.

HS 412
N169 (H II Region)
RA 05 46 33.9 Dec -69 34 22 Mag –
Size A = 0.4ʹ; B = 0.2ʹ; C = 1.5ʹ x 1.4ʹ
16″ at 228x + UHC filter: N169 has three components: N169A is the brightish round one in the centre with small B below it and large C to its right. But the only component that I can see is N169A; it appears as a very faint and small, round glow, with soft edges that fade out. There is an extremely faint hint of C’s nebulosity; not so much a glow as the impression of a glow.

N169