Steve Gottlieb
July 31st, 2013, 07:32 PM
6) Bean Nebula (LMC-N11 Complex)
NGC 1763 (30"): The Bean Nebula complex (LHA 120-N11) is the second largest stellar nursery in the LMC after the Tarantula Nebula. The showpiece is NGC 1763, the Bean Nebula, which sits near the center of a stunning field of emission nebulae and clusters including NGC 1760 7' S, NGC 1761 3' S, NGC 1769 6.5' SE, NGC 1773 8' ENE and NGC 1776 11' E. NGC 1763 is a very bright, very large irregular nebula, shaped like a kidney-bean or a fetus. The main body extends 5'x3', elongated SW-NE with a bulbous portion on the NE wide and an indentation (weaker nebulosity) on the south side. Overall the surface brightness is very high, though uneven, and much fainter haze and filaments flow out from the Bean in most directions. Within the main body, the nebula is brightest in a loop on the SW side and secondly in a section on the NE side. Superimposed on the Bean Nebula is a large cluster, catalogued as stellar association LH 10, with roughly two dozen stars resolved including a number of 12-13th magnitude stars. On the NE end is an E-W string of 3 stars along with IC 2116, a bright, high surface brightness knot, ~15" diameter. Very faint haze at the edge of NGC 1763 appears to extend from IC 2116. The surrounding field is rich in stars between the individual objects with some individual locally brighter knots of nebulosity.
NGC 1760 (30"): appears as a 1.7' E-W string of a half-dozen stars over fairly bright nebulosity. The emission haze is brightest just south of the string and extending to the west of the string a couple of arc minutes. Irregular nebulosity also branches out to the south of the string for another 2' and involves a mag 12 star. Another 2' string of N-S stars is on the west side of the haze.
NGC 1760 is at the SW end of a stunning complex (LHa 120-N11) of clusters and nebulosity including NGC 1763 = Bean Nebula, a showpiece nebula and cluster centered 7' NE; NGC 1761, a larger cluster and nebulosity just 3' N; NGC 1769, a bright emission nebula 8' NE; along with NGC 1773, NGC 1776 and IC 2115. Lucke and Hodge assign NGC 1760 and 1761 to stellar association LH 9.
NGC 1761 (30"): bright, large cluster sandwiched between the showpiece Bean Nebula (NGC 1763) to the north and NGC 1760 to the south. There are roughly 80 stars mag 11 to 16 in a 3.5' irregularly shaped group over some background haze. The stars are fairly even distributed except for a detached 1.3' group of 10-12 stars off the NW side. Including this detached section, the overall size of this star cloud (association LH 9) is 5'x3.5'. A close bright double star (probably h3716 = 10.2/10.9 at 5") is on the NW side of the main group.
IC 2116 (30"): bright, high surface brightness knot, ~15" diameter. Located at the NE edge of the showpiece Bean Nebula (NGC 1763), roughly 3' NE of the center, and certainly part of the same complex. Very faint haze at the edge of NGC 1763 appears to extend from IC 2116. IC 2115 appears to be a mag 11 star, just 0.8' W, although there is no emission so this identification may be incorrect.
NGC 1769 (30"): bright, large oval nebula oriented SW-NE, roughly 3'x2'. There are three or four stars in the center with the brightest 12th magnitude. A small, bright knot is on the south side, just 1' S of the mag 12 star. Roughly centered within the stunning NGC 1763 (Bean Nebula) complex with showpiece NGC 1763 just 6.5' NW, NGC 1761 6' WSW, NGC 1776 6' NE, NGC 1760 8' SW and NGC 1773 7' NNE.
NGC 1773 (30"): fairly large, bright glow, oval 3:2, 2.2'x1.5'. On first glance, two brighter stars are offset SW of the geometric center and separated by 15", but on closer inspection the more central star resolves into a very close double. In additional a couple of fainter stars are superimposed on the north side of the glow. The nebulosity is slightly irregular in surface brightness and brighter along the rim, particularly on the SW side. This emission nebula is located at the NE end of the NGC 1763 (Bean Nebula) complex with NGC 1763 centered 9' SW, NGC 1769 7' SSW and NGC 1776 5' SSE.
NGC 1776 (30"): located on the east side of the NGC 1763 (Bean Nebula) complex, this cluster is moderately bright, fairly small. Well concentrated with a small bright core surrounded by a 50" halo. A couple of extremely faint stars are just visible in the halo. Located 5' SE of emission nebula NGC 1773, 6' ENE of emission nebula NGC 1769 and 2.7' NE of a mag 10.8 star.
NGC 1763 (30"): The Bean Nebula complex (LHA 120-N11) is the second largest stellar nursery in the LMC after the Tarantula Nebula. The showpiece is NGC 1763, the Bean Nebula, which sits near the center of a stunning field of emission nebulae and clusters including NGC 1760 7' S, NGC 1761 3' S, NGC 1769 6.5' SE, NGC 1773 8' ENE and NGC 1776 11' E. NGC 1763 is a very bright, very large irregular nebula, shaped like a kidney-bean or a fetus. The main body extends 5'x3', elongated SW-NE with a bulbous portion on the NE wide and an indentation (weaker nebulosity) on the south side. Overall the surface brightness is very high, though uneven, and much fainter haze and filaments flow out from the Bean in most directions. Within the main body, the nebula is brightest in a loop on the SW side and secondly in a section on the NE side. Superimposed on the Bean Nebula is a large cluster, catalogued as stellar association LH 10, with roughly two dozen stars resolved including a number of 12-13th magnitude stars. On the NE end is an E-W string of 3 stars along with IC 2116, a bright, high surface brightness knot, ~15" diameter. Very faint haze at the edge of NGC 1763 appears to extend from IC 2116. The surrounding field is rich in stars between the individual objects with some individual locally brighter knots of nebulosity.
NGC 1760 (30"): appears as a 1.7' E-W string of a half-dozen stars over fairly bright nebulosity. The emission haze is brightest just south of the string and extending to the west of the string a couple of arc minutes. Irregular nebulosity also branches out to the south of the string for another 2' and involves a mag 12 star. Another 2' string of N-S stars is on the west side of the haze.
NGC 1760 is at the SW end of a stunning complex (LHa 120-N11) of clusters and nebulosity including NGC 1763 = Bean Nebula, a showpiece nebula and cluster centered 7' NE; NGC 1761, a larger cluster and nebulosity just 3' N; NGC 1769, a bright emission nebula 8' NE; along with NGC 1773, NGC 1776 and IC 2115. Lucke and Hodge assign NGC 1760 and 1761 to stellar association LH 9.
NGC 1761 (30"): bright, large cluster sandwiched between the showpiece Bean Nebula (NGC 1763) to the north and NGC 1760 to the south. There are roughly 80 stars mag 11 to 16 in a 3.5' irregularly shaped group over some background haze. The stars are fairly even distributed except for a detached 1.3' group of 10-12 stars off the NW side. Including this detached section, the overall size of this star cloud (association LH 9) is 5'x3.5'. A close bright double star (probably h3716 = 10.2/10.9 at 5") is on the NW side of the main group.
IC 2116 (30"): bright, high surface brightness knot, ~15" diameter. Located at the NE edge of the showpiece Bean Nebula (NGC 1763), roughly 3' NE of the center, and certainly part of the same complex. Very faint haze at the edge of NGC 1763 appears to extend from IC 2116. IC 2115 appears to be a mag 11 star, just 0.8' W, although there is no emission so this identification may be incorrect.
NGC 1769 (30"): bright, large oval nebula oriented SW-NE, roughly 3'x2'. There are three or four stars in the center with the brightest 12th magnitude. A small, bright knot is on the south side, just 1' S of the mag 12 star. Roughly centered within the stunning NGC 1763 (Bean Nebula) complex with showpiece NGC 1763 just 6.5' NW, NGC 1761 6' WSW, NGC 1776 6' NE, NGC 1760 8' SW and NGC 1773 7' NNE.
NGC 1773 (30"): fairly large, bright glow, oval 3:2, 2.2'x1.5'. On first glance, two brighter stars are offset SW of the geometric center and separated by 15", but on closer inspection the more central star resolves into a very close double. In additional a couple of fainter stars are superimposed on the north side of the glow. The nebulosity is slightly irregular in surface brightness and brighter along the rim, particularly on the SW side. This emission nebula is located at the NE end of the NGC 1763 (Bean Nebula) complex with NGC 1763 centered 9' SW, NGC 1769 7' SSW and NGC 1776 5' SSE.
NGC 1776 (30"): located on the east side of the NGC 1763 (Bean Nebula) complex, this cluster is moderately bright, fairly small. Well concentrated with a small bright core surrounded by a 50" halo. A couple of extremely faint stars are just visible in the halo. Located 5' SE of emission nebula NGC 1773, 6' ENE of emission nebula NGC 1769 and 2.7' NE of a mag 10.8 star.