We have observed the massive star forming region associated with the early B protostar G192.16–3.84 in NH _ { 3 } ( 1,1 ) , 22.2 GHz H _ { 2 } O masers , 1.3 cm continuum emission , and at 850 \mu m. The dense gas associated with G192.16 is clumpy , optically thin , and has a mass of 0.9 M _ { \odot } .
The NH _ { 3 } core is gravitationally unstable which may signal that the outflow phase of this system is coming to an end .
Water masers trace an ionized jet 0.8 ^ { \prime \prime } ( 1600 AU at a distance of 2 kpc ) north of G192.16 .
Masers are also located within 500 AU of G192.16 , their velocity distribution is consistent with but does not strongly support the interpretation that the maser emission arises in a 1000 AU rotating disk centered on G192.16 .
Roughly 30 ^ { \prime \prime } south of G192.16 ( 0.3 pc ) is a compact , optically thick ( \tau = 1.2 ) NH _ { 3 } core ( called G192 S3 ) with an estimated mass of 2.6 M _ { \odot } .
Based on the presence of 850 \mu m and 1.2 mm continuum emission , G192 S3 probably harbors a very young , low-mass protostar or proto-cluster .
The dense gas in the G192 S3 core is likely to be gravitationally bound and may represent the next site of star formation in this region .