Mission Name SNOE: The Student Nitric Oxide Explorer SNOE Mission Patch Download LASP SNOE Poster (1892 kb) LASP Instruments Principal Investigator: Charles Barth Destination approx 570 km Earth Orbit Launch Date February 25th, 1998 Launch Location Vandenberg Air Force Base Launch Vehicle Pegasus XL Mission Duration 5 years Mission Description/ LASP involvement   LASP Divisions Involved Engineering * Science * Operations LASP Mission Web Page http://lasp.colorado.edu/snoe/ Official Mission Web Page

The Student Nitric Oxide Explorer (SNOE) measured nitric oxide density in the Earth's lower thermosphere (100-200 km altitude) and analyzed how the Sun and the Earth's magnetosphere affect its abundance. SNOE carried three instruments: an ultraviolet spectrometer to measure nitric oxide altitude profiles, a two-channel auroral photometer to measure auroral emissions beneath the spacecraft, and a five-channel solar soft X-ray photometer. Under the supervision of LASP and industry mentors, University of Colorado students worked on the design study, built the spacecraft and instruments, wrote the flight software, integrated and tested the instruments and subsystems, and integrated with the launch vehicle.

Nitric oxide is an important minor constituent of the upper atmosphere that exhibits strong solar-terrestrial coupling. Nitric oxide directly affects the composition of the ionosphere, the thermal structure of the thermosphere, and may be transported downward into the mesosphere and stratosphere where it can react with ozone. However, significant unanswered questions about nitric oxide remain. The scientific objectives of the Student Nitric Oxide Explorer are:

• To determine how variations in the solar soft X-radiation produce changes in the density of nitric oxide in the lower thermosphere,
• To determine how auroral activity produces increased nitric oxide in the polar regions.