The Tropospheric Emission Spectrometer (TES) launched into sun-synchronous orbit aboard Aura, the third of NASA's Earth Observing System (EOS) spacecraft, on July 15, 2004. The primary objective of TES is to make global, three-dimensional measurements of ozone and other chemical species involved in its formation and destruction.

TES is a high-resolution imaging infrared Fourier-transform spectrometer that operates in both nadir and limb-sounding modes. TES global survey standard products include profile measurements of ozone, water vapor, carbon monoxide, methane, nitrogen dioxide, and nitric acid for 16 orbits every other day. TES Special Observations are research measurements of targeted locations or regional transects which are used to observe specific phenomena or to support local or aircraft validation campaigns.

The TES Level 1B products are written in NCSA's HDF5 format. The Level 2 and Level 3 data products are written in HDF-EOS5 (based on HDF5) format. The TES Lite products, under Level 2, are intended to simplify TES data usage including data /model and data/data comparisons. This product can be used for science analysis as each data product is fully characterized.

On Jan. 31 2018, NASA ended the Tropospheric Emission Spectrometer's almost-14-year career of discovery.   At 11:00am PST during a scheduled real time satellite contact the TES IOT along with the Aura FOT commanded the TES instrument to its decommissioned state.  The transition occurred as planned, there were no complications.  A full NASA press release for the TES instrument can be found here "Farewell to a Pioneering Pollution Sensor".

The scientific discovery mission of Tropospheric Emission Spectrometer has concluded.  However, a final full TES dataset (v008) will be generated from an algorithm update to the base Ground Data System software and will be made available to the scientific community in the next two years.