In its core there are many protostars and many infrared sources; some of these sources, like IRAS 18151−1208, are most probably very young high-mass stars. The older star population in this region has an average age of 4-5 millions years, and its components are grouped in the open clusterNGC 6604.
^Davis, C. J.; Varricatt, W. P.; Todd, S. P.; Ramsay Howat, S. K. (October 2004). "Collimated molecular jets from high-mass young stars: IRAS 18151-1208". Astronomy and Astrophysics425 (3): 981–995. Bibcode:2004A&A...425..981D. doi:10.1051/0004-6361:20041298.Unknown parameter |rivista= ignored (help)
^Sofue, Y.; Handa, T.; Fuerst, E.; Reich, W.; Reich, P. (1986). "Giant stellar-wind shell associated with the H II region M16". Astronomical Society of Japan38: 347–360. Bibcode:1986PASJ...38..347S.