MIRO: Water vapour from 67P/C-G

Well over a decade ago, QMC Instruments made a small free standing wire polarizing grid which JPL's MIRO instrument on the Rosetta mission uses to separate incoming radiation into two channels: Two radiometers have been looking at 188 GHz (1.6 mm) and 562 GHz (0.5 mm). The lower band provides continuum measurements, giving subsurface temperature measurements, the higher frequency channel cover vibration lines which include H₂O, CO, CH₃OH, and NH₃ and the isotopes H₂¹⁷O and H₂¹⁸O

Worth reading the ESA MIRO Blog here

Image thanks to ESA

MIRO has been measuring the rate of Water Loss from 67P/C-G.  At its peak we are told here that the comet is losing 5 Liters a second...