NGC 346 | |
---|---|
Observation data (J2000 epoch) | |
Right ascension | 00h 59m 05.090s [1] |
Declination | −72° 10′ 33.24″ [1] |
Distance | 210,000 light-years |
Physical characteristics | |
H II region | |
Other designations | ESO 51-10, [2] N66 |
Associations | |
Constellation | Tucana [3] |
NGC 346 is a young [4] open cluster of stars with associated nebula located in the Small Magellanic Cloud (SMC) that appears in the southern constellation of Tucana. It was discovered August 1, 1826 by Scottish astronomer James Dunlop. J. L. E. Dreyer described it as, "bright, large, very irregular figure, much brighter middle similar to double star, mottled but not resolved". [5] On the outskirts of the cluster is the multiple star system HD 5980, [6] one of the brightest stars in the SMC.
This cluster is located near the center of the brightest H II region in the SMC, designated N66. [7] This is positioned in the northeast section of the galactic bar. [8] Stellar surveys have identified 230 massive OB stars in the direction of this cluster. [4] 33 of the cluster members are O-type stars, with 11 of type O6.5 or earlier. [8] The inner 15 pc radius of the cluster appears centrally condensed, while the area outside that volume is more dispersed. [9] The youngest cluster members near the center have ages of less than two million years, [7] and observations suggests the cluster is still engaged in high mass star formation. [7] The cluster star formation rate is estimated at (4±1)×10−3 M☉ yr−1. [9]
Recent observations [10] by NASA's James Webb Space Telescope have provided unprecedented insights into NGC 346. These observations have revealed surprising details about the cluster's dust environment, challenging previous assumptions and shedding light on the processes of protostar formation and early planetary development within this dynamic stellar nursery. Webb's observations mark a significant advancement in our understanding of star formation in the Small Magellanic Cloud and offer exciting avenues for further research into the cosmic evolution of galaxies.
Walborn | ELS | MPG | NMC | SSN | Spectral type | Effective temperature ( K ) | Absolute magnitude | Bolometric magnitude | Mass (M☉) |
---|---|---|---|---|---|---|---|---|---|
207758 | 755 (HD 5980/AB5) | LBV WN4 OI | 45,000 45,000 34,000 | −7.1 (−8.1) −6.8 −6.7 | −11.135 −10.885 −9.885 | 61 66 34 | |||
1 | 435 | 26 | 7 | O5.5If | 43,400 | −6.7 | −10.7 | 91 | |
1 | 789 | 5 | O7If | 38,900 | −7 | −10.7 | 85 | ||
3 | 355 | 29 | 9 | O3V | 51,300 | −5.7 | −10.3 | 76 | |
6 | 7 | 324 | 32 | 13 | O4V | 48,600 | −5.2 | −9.6 | 54 |
4 | 342 | 30 | 11 | O5.5V | 44,900 | −5.5 | −9.7 | 53 | |
368 | 28 | 15 | O5.5V | 44,900 | −5 | −9.2 | 43 | ||
2 | 470 | 25 | O8.5III | 35,700 | −5.4 | −8.9 | 34 | ||
NGC 3603 is a nebula situated in the Carina–Sagittarius Arm of the Milky Way around 20,000 light-years away from the Solar System. It is a massive H II region containing a very compact open cluster HD 97950.
R136 is the central concentration of stars in the NGC 2070 star cluster, which lies at the centre of the Tarantula Nebula in the Large Magellanic Cloud. When originally named it was an unresolved stellar object but is now known to include 72 class O and Wolf–Rayet stars within 5 parsecs of the centre of the cluster. The extreme number and concentration of young massive stars in this part of the LMC qualifies it as a starburst region.
NGC 290 is an open cluster of stars in the southern constellation of Tucana. This cluster was discovered September 5, 1826, by Scottish astronomer James Dunlop. It lies some 200,000 light years away from the Sun in the Small Magellanic Cloud galaxy. The cluster is an estimated 30–63 million years old and is around 65 light years across.
NGC 265 is an open cluster of stars in the southern constellation of Tucana. It is located in the Small Magellanic Cloud, a nearby dwarf galaxy. The cluster was discovered by English astronomer John Herschel on April 11, 1834. J. L. E. Dreyer described it as, "faint, pretty small, round", and added it as the 265th entry in his New General Catalogue.
NGC 2060 is a star cluster within the Tarantula Nebula in the Large Magellanic Cloud, very close to the larger NGC 2070 cluster containing R136. It was discovered by John Herschel in 1836. It is a loose cluster approximately 10 million years old, within one of the Tarantula Nebula's superbubbles formed by the combined stellar winds of the cluster or by old supernovae.
R136b is a blue supergiant star in the R136 cluster in the Large Magellanic Cloud. It is one of the most massive and most luminous stars known. It is found in the dense R136 open cluster at the centre of NGC 2070 in the Tarantula Nebula.
R136a1 is one of the most massive and luminous stars known, at nearly 200 M☉ and nearly 4.7 million L☉, and is also one of the hottest, at around 46,000 K. It is a Wolf–Rayet star at the center of R136, the central concentration of stars of the large NGC 2070 open cluster in the Tarantula Nebula in the Large Magellanic Cloud. The cluster can be seen in the far southern celestial hemisphere with binoculars or a small telescope, at magnitude 7.25. R136a1 itself is 100 times fainter than the cluster and can only be resolved using speckle interferometry.
HD 5980 is a multiple star system on the outskirts of NGC 346 in the Small Magellanic Cloud (SMC) and is one of the brightest stars in the SMC.
AB7, also known as SMC WR7, is a binary star in the Small Magellanic Cloud. A Wolf–Rayet star and a supergiant companion of spectral type O orbit in a period of 19.56 days. The system is surrounded by a ring-shaped nebula known as a bubble nebula.
R136a2 is a Wolf-Rayet star residing near the center of the R136, the central concentration of stars of the large NGC 2070 open cluster in the Tarantula Nebula, a massive H II region in the Large Magellanic Cloud which is a nearby satellite galaxy of the Milky Way. It has one of the highest confirmed masses and luminosities of any known star, at about 151 M☉ and 3.5 million L☉ respectively.
R136c is a star located in R136, a tight knot of stars at the centre of NGC 2070, an open cluster weighing 450,000 solar masses and containing 10,000 stars. At 142 M☉ and 3.8 million L☉, it is the one of the most massive stars known and one of the most luminous, along with being one of the hottest, at over 40,000 K. It was first resolved and named by Feitzinger in 1980, along with R136a and R136b.
R136a3 is a Wolf–Rayet star in R136, a massive star cluster located in Dorado. It is located near R136a1, the most massive and luminous star known. R136a3 is itself one of the most massive and most luminous stars known at about 179 times more massive and 5 million times more luminous than the Sun.
BI 253 is an O2V star in the Large Magellanic Cloud and is a primary standard of the O2 type. It is one of the hottest main-sequence stars known and one of the most-massive and most-luminous stars known.
Westerhout 43, also known as W43, is a region of star formation of our galaxy located in the constellation of Aquila at a distance of 6 kilo-parsecs of the Sun, that is considered the region of the Milky Way that is most actively forming stars. Despite this, however, it is so heavily obscured by the interstellar dust that it is totally invisible in the optical and must be studied using other wavelengths that are not affected by it, such as the infrared or the radio waves.
BAT99-98 is a Wolf–Rayet star located in the Large Magellanic Cloud, in NGC 2070 near the R136 cluster in the Tarantula Nebula. At 226 M☉ and 5,000,000 L☉ it is one of the most massive and luminous stars currently known.
NGC 121 is a globular cluster of stars in the southern constellation of Tucana. It is the oldest globular cluster in the Small Magellanic Cloud (SMC), which is a dwarf satellite galaxy of the Milky Way. This cluster was first discovered by English astronomer John Herschel on September 20, 1835. The compiler of the New General Catalogue, Danish astronomer John Louis Emil Dreyer, described this object as "pretty bright, pretty small, little extended, very gradually brighter middle". The cluster is located at a distance of around 200,000 light-years (60 kpc) from the Sun.
AB8, also known as SMC WR8, is a binary star in the Small Magellanic Cloud (SMC). A Wolf-Rayet star and a main sequence companion of spectral type O orbit in a period of 16.638 days. It is one of only nine known WO stars, the only Wolf-Rayet star in the SMC not on the nitrogen sequence, and the only Wolf-Rayet star in the SMC outside the main bar.
NGC 299 is an open cluster of stars in the main body of the Small Magellanic Cloud – a nearby dwarf galaxy. It is located in the southern constellation of Tucana, just under 200,000 light years distant from the Sun. The cluster was discovered on August 12, 1834, by English astronomer John Herschel.