The circular 'keyhole' structure contains both bright filaments of hot gas and dark silhouetted clouds of cold molecules and dust, all of which are in rapid, chaotic motion. Two striking large, sharp-edged dust clouds are located near the bottom centre and upper-left edges of the image. These large dark clouds may eventually evaporate or, if there are sufficiently dense condensations within them, give birth to small star clusters.

https://www.esa.int/Science_Exploration/Space_Science/Space_sensations/Carina_Nebula_NGC_3372