Selected science highlights from the first 5 years of the Upper Atmosphere Research Satellite (UARS) Program

We present scientific highlights from the Upper Atmosphere Research Satellite (UARS) program obtained during the first 5 years of the program. The UARS measures the chemical composition and meteorological state of the middle and upper atmosphere as well as the solar irradiance. The comprehensive suite of UARS geophysical parameters, their near‐global coverage, and the multiyear time span have yielded new insights into the processes affecting our atmosphere. In this article we select seven scientific issues, including stratospheric ozone chemistry, the dynamics of the middle and upper atmosphere, and solar irradiance variations, and discuss the significant impact that the UARS observations have had on our understanding of each issue.