Spectra of three knots of “Green Fuzzy” emission

Spectra of three knots of “Green Fuzzy” emission around the G19.88-0.53 MYSO obtained with NIRI on Gemini North. The shaded area marks the passband of the Spitzer filter and includes the wavelength of the molecular hydrogen transition labeled S(9). This emission line is responsible for the enhanced emission in the Spitzer 4.5 micron band and causes the knots to appear “green.” Additional H₂ lines detected in the NIRI spectra are denoted with vertical dashed lines.