LMC 6 Supergiant Shell

A beautiful emission nebula, a Wolf-Rayet Bubble and an oddly named SNR

Image credit & copyright: Team Ciel Austral

RA: 04h 59m Dec: -68° 36′

Diameter: 1,900 light-years

OB Associations: LH 11, 12

NGC Objects: NGC 1770

Supergiant Shell LMC 6

LMC 6 is a small, oblong SGS located in the southwest of the Large Magellanic Cloud. The OB association LH 12, in the northwest corner of LMC 6, is in a bright large H II region N91, from which tails of ionized gas arc to the east. The OB association LH 11 is located on the outer edge of the shell’s southern periphery. The shell is delineated by long ionized filaments stretching along its circumference (Book et al, 2009).

LMC 6’s pièce de résistance is N91, and it is one of the Cloud’s prettiest objects, quite apart from the fact it also contains a rare visual treat – a Wolf-Rayet bubble. The SGS also contains the “Lionel Murphy SNR” – it’s not often that one sees someone’s nose immortalised in a supernova remnant!

Low magnification overview

At low magnification with the filter, this superbubble is eye-catching! N91 is gorgeous! Bright and uneven with nicely defined edges, and crying out for magnification. N92 at the southern end of the supergiant shell is a tiny splotch; small but bright. Murphy’s famous nose, N86, is intriguing, appearing as a large, very faint round glow. It’s very uneven, but because it’s so faint you can’t actually define the unevenness. Without the filter, the brighter stars of LH 12 look like tiny crystal chips studding the nebulosity; just lovely. SL 134 is a small but brightish little glow, and smaller SL 105 is a brightish, small round glow.

N91 Complex

An exquisite complex and Wolf-Rayet bubble

N91

N91 Complex

An exquisite complex and Wolf-Rayet bubble

N91

N86 Supernova Remnant

A SNR named after an Australian’s nose

N86 Supernova Remnant

A SNR named after an Australian’s nose

N86 Supernova Remnant

N80 (H II Region)

RA 04 54 13.4 Dec -68 21 52 Mag = – Size 5.0ʹ x 4.0ʹ

16″ at 228x + UHC filter: N80 appears as a fairly bright, small, round patch of mistiness with no discernible edges, the mistiness simply melts away into the surrounding sky. Without the filter, a very small and very faint star in its centre pops in and out of view.

N80

KMHK 245 (Open Cluster)

RA 04 54 27.9 Dec -68 27 41 Mag – Size 0.9ʹ x 0.8ʹ

16″ at 228x: This cluster appears as a very faint and small smudge. Mag 11.5 HD 268741 lies 1′ ENE.

KMHK 245

SL 105 (Open Cluster)

RA 04 55 24.3 Dec -68 32 27 Mag 12.2 Size 1.4ʹ

16″ at 228x: SL 105 appears fairly bright, very slightly off-round, ~20″ in diameter, with no resolved stars.

SL 105

N84 (Emission object)

RA 04 55 34.5 Dec -68 25 39 Size 2.1ʹ x 2.0ʹ

16″ at 228x + UHC filter: N84 appears a very faint, very small, round patch of diffuse mistiness with no discernible edges; its very faint glow just melts away.

N84

SL 116 (Open Cluster)

RA 04 56 25.3 Dec -68 48 18 Mag 12.3 Size 1.4′ x 1.3′

16″ at 228x: Lying right on the southern periphery of the SGS, SL 116 appears as a bright, round glow, 20″ in diameter, with no stars resolved.

SL 116

LH 11 + N92 (OB Association + Emission Nebula)

RA 04 57 05.8 Dec -68 44 58 Size 1.5ʹ x 1.0ʹ

16″ at 228x: LH 11 is ~1ʹ x 45″ in size and elongated NE-SW. It appears to have two parts separated by a narrow starless gap. The small cluster HS 74 lies on the SW side, and it has a couple of very small, resolved stars set against a round, faint glow of unresolved stars. On the NE side there is a small, bright knot of stars with one star resolved to its southwest. The stars are encased in N92’s faint and misty nebulosity. At 228x with the UHC filter, N92 appears as a faint and soft, hazy nebulous glow surrounding the two sets of stars, with edges that melt away into the surrounding sky.

LH 11 + N92

SL 176 (Open Cluster)

RA 05 01 28.2 Dec -68 42 45 Mag – Size 1.0′ x 0.9′

16″ at 228x: SL 176 appears to lie right on the eastern periphery of the SGS. It appears as a very faint, round droplet of light, ~10″ in diameter, and with a ~mag 14.5 star lying off its western side.

SL 176

WOH G64 (Red Supergiant Star)

RA 04 55 10.5 Dec -68 20 30 Mag 17.7 to 18.8

In October 2024, a team of astronomers published this stunning image of WOH G64… the first detailed interferometric image of an RSG outside the Milky Way! It is an extremely large star 1540 times the size of the Sun – easily the largest in the LMC! But alas, it is vanishingly faint at mag 17.7 to 18.8. You can read a fascinating write-up about this extreme star here.