MOPITT provides retrievals of CO profiles and total column in the troposphere. It uses the thermal IR at 4.3 microns, which is sensitive to a CO band. MOPITT is a correlated radiometer which modulates the gas cell. It uses a Length Modulated Cell (LMC), which is more sensitive at around 500 hPa. There is also a Pressure Modulated Cell (PMC), which is more sensitive around 300 hPa. Together they contribute to a profile of CO in the troposphere. Measurements Of Pollution In The Troposphere (MOPITT) was successfully launched into sun-synchronous polar orbit aboard Terra, NASA's first Earth Observing System spacecraft on December 18, 1999. The MOPITT instrument was constructed by a consortium of Canadian companies and funded by the Space Science Division of the Canadian Space Agency.