NGC 346

NGC 346 is a young open cluster of stars within an associated emission nebula located in the Small Magellanic Cloud (SMC) that appears in the southern constellation of Tucana. It was discovered in 1826 by Scottish astronomer James Dunlop.
The cluster has a diameter of 150 light-years and a mass 50.000 that of the Sun.
This cluster is located near the center of the brightest H II region in the SMC, designated N66. Stellar surveys have identified 230 massive OB stars in the direction of this cluster. 33 of the cluster members are O-type stars, with 11 of type O6.5 or earlier. These are high-mass stars, with ranges between 34 and 91 solar masses. The youngest cluster members near the center have ages of less than two million years, and observations suggests the cluster is still engaged in high mass star formation.
The classical study of the color-magnitude diagram (CMD) shows that the star formation increased in the last 100 million years. The study also shows that the cluster itself is divided in several subclusters, with different masses and origins. The diffuse component was formed between 5-7 billion years ago. The clustered component started forming 6 million years ago and continues the star-forming activity at a slower pace even today.
James Webb Space Telescope (JWST) observed this cluster in the infrared domain and several protoplanetary discs were distinguished around the low-mass stars.