NGC 346

NGC 346
James Webb Space Telescope image of NGC 346
Observation data (J2000 epoch)
Right ascension00h 59m 05.090s[1]
Declination−72° 10′ 33.24″[1]
Distance210,000 light-years
Physical characteristics
H II region
Other designationsESO 51-10,[2] N66
Associations
ConstellationTucana[3]
See also: Open cluster, List of open clusters

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.

  • Image of NGC 346 with a 30 arcminute wide field of view showing the wispy nebular structure around it.
    Image of NGC 346 with a 30 arcminute wide field of view showing the wispy nebular structure around it.
Prominent stars[11]
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
  1. ^ a b Cite error: The named reference Sturm2013 was invoked but never defined (see the help page).
  2. ^ Cite error: The named reference simbad was invoked but never defined (see the help page).
  3. ^ Cite error: The named reference her was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference Dufton2020 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference cseligman was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference Nazé2002 was invoked but never defined (see the help page).
  7. ^ a b c Cite error: The named reference Dufton2019 was invoked but never defined (see the help page).
  8. ^ a b Cite error: The named reference Rubio2018 was invoked but never defined (see the help page).
  9. ^ a b Cite error: The named reference Hony2015 was invoked but never defined (see the help page).
  10. ^ "Webb Discovers Star Formation in Dusty Ribbons of a star cluster NGC 346". www.jameswebbdiscovery.com. Retrieved 2024-02-20.
  11. ^ Massey, Philip; Waterhouse, Elizabeth; DeGioia-Eastwood, Kathleen (May 2000). "The Progenitor Masses of Wolf-Rayet Stars and Luminous Blue Variables Determined from Cluster Turnoffs. I. Results from 19 OB Associations in the Magellanic Clouds". The Astronomical Journal. 119 (5): 2214–2241. arXiv:astro-ph/0002233. Bibcode:2000AJ....119.2214M. doi:10.1086/301345. ISSN 0004-6256. S2CID 16891188.