The Atmospheric Trace Molecule Spectroscopy Experiment (ATMOS) was carried onboard several of NASA's space shuttles. It was designed to study the composition of the atmosphere from space. 

The data were collected during four shuttle missions: 

• STS-51B/Spacelab 3 (April 30 to May 1, 1985) 
• STS-45/ATLAS-1 (March 25 to April 2, 1992) 
• STS-56/ATLAS-2 (April 8 to 16, 1993) 
• STS-66/ATLAS-3 (November 3 to 12, 1994).